Search Results

Search found 988 results on 40 pages for 'lambda dusk'.

Page 40/40 | < Previous Page | 36 37 38 39 40 

• CodePlex Daily Summary for Tuesday, July 10, 2012

  CodePlex Daily Summary for Tuesday, July 10, 2012Popular ReleasesjListSelect - jQuery plug-in for a fully customizable select input: 1.0: This is the initial release. Documentation is available using the Documentation tab above and inside the JavaScript code.Push Framework: Push Framework 1.5: This version brings many bug fixes and enhancements to its predecessor.DbDiff: Database Diff and Database Scripting: 1.1.3.3: Sql 2005, Sql 2012 fixes Removed dbdiff recommended default exe because it was a wrong build.re-linq: 1.13.158: This is build 1.13.158 of re-linq. Find the complete release notes for the build here: Release NotesMishra Reader: Mishra Reader beta 3: Per-feed browsing Tons of bug fixes Note: This release requires .NET 4.5 RC. You'll be prompted to install it if you don't already have it. The RC will be upgradeable to the RTM once it's available.MVVM Light Toolkit: MVVM Light Toolkit V4 RTM: The issue with the installer is fixed, sorry for the problems folks This version supports Silverlight 3, Silverlight 4, Silverlight 5, WPF 3.5 SP1, WPF4, Windows Phone 7.0 and 7.5, WinRT (Windows 8). Support for Visual Studio 2010 and Visual Studio 2012 RC.BlackJumboDog: Ver5.6.7: 2012.07.08 Ver5.6.7 (1) ????????????????「?????　Request.Receve()」?????????? (2) Web???????????FlMML customized: FlMML customized ??: FlMML customized ????。 ??、ＰＣＭ??????????、??????。ecBlog: ecBlog 0.2: ecBlog alpha realaseTaskScheduler ASP.NET: Release 3 - 1.2.0.0: Release 3 - Version 1.2.0.0 That version was altered only the library: In TaskScheduler was added new properties: UseBackgroundThreads Enables the use of separate threads for each task. StoreThreadsInPool Manager enables to store in the Pool threads that are performing the tasks. OnStopSchedulerAutoCancelThreads Scheduler allows aborting threads when it is stopped. false if the scheduler is not aborted the threads that are running. AutoDeletedExecutedTasks Allows Manager Delete Task afte...DotNetNuke Persian Packages: ??? ?? ???? ????? ???? 6.2.0: *????? ???? ??? ?? ???? 6.2.0 ? ??????? ???? ????? ???? ??? ????? *????? ????? ????? ??? ??? ???? ??? ??????? ??????? - ???? *?????? ???? ??? ?????? ?? ???? ???? ????? ? ?? ??? ?? ???? ???? ?? *????? ????? ????? ????? ????? / ??????? ???? ?? ???? ??? ??? - ???? *???? ???? ???? ????? ? ??????? ??? ??? ??? ?? ???? *????? ????? ???????? ??? ? ??????? ?? ?? ?????? ????? ????????? ????? ?????? - ???? *????? ????? ?????? ????? ?? ???? ?? ?? ?? ???????? ????? ????? ????????? ????? ?????? *???? ?...Cypher Bot: Cypher Bot 4.1: Cypher Bot is the most advanced encryption tool on the planet.... and now it actually works. That's right we fixed the bugs! For a full program summary go to the Home Page or visit www.iRareMedia.com So what's new? We've pretty much fixed all the bugs, but here's a run down if you wanna know exactly what's different: Fixed Installation / Setup Error, where an error message would display: "No Internet Connection, Try Again Later" Fixed File Encryption / Decryption error where the file exten...Coding4Fun Kinect Service: Coding4Fun Kinect Service v1.5: Requires Kinect for Windows SDK v1.5 Minor bug fixes + Kinect for Windows SDK v1.5 Aligning version with the Kinect for Windows SDK requiredtedplay: tedplay 1.1: tedplay 1.1 source and Win32 binary is out now. Changes are: SID card support Commodore 64 PSID music format support optimized FIR filter global hotkeys for skipping tracks (Windows only) module properties window (Windows only) mutable noise channel via GUI button (Windows only) disable SID card from the menu (Windows only) bugfixes PSID tunes are played on the C64 clock frequency but in a Commodore plus/4 virtual machine. The purpose is not to have yet another SID player, but t...xUnit.net Contrib: xunitcontrib-resharper 0.6 (RS 7.0, 6.1.1): xunitcontrib release 0.6 (ReSharper runner) This release provides a test runner plugin for Resharper 7.0 (EAP build 82) and 6.1, targetting all versions of xUnit.net. (See the xUnit.net project to download xUnit.net itself.) Copies of the plugin that support previous verions of ReSharper can be downloaded from this release. The plan is to support the latest revisions of the last two paid-for major versions of ReSharper (namely 7.0 and 6.1) Also note that all builds work against ALL VERSIONS...Umbraco CMS: Umbraco 4.8.0 Beta: Whats newuComponents in the core Multi-Node Tree Picker, Multiple Textstring, Slider and XPath Lists Easier Lucene searching built in IFile providers for easier file handling Updated 3rd party libraries Applications / Trees moved out of the database SQL Azure support added Various bug fixes Getting Started A great place to start is with our Getting Started Guide: Getting Started Guide: http://umbraco.codeplex.com/Project/Download/FileDownload.aspx?DownloadId=197051 Make sure to...CODE Framework: 4.0.20704.0: See CODE Framework (.NET) Change Log for changes in this version.xUnit.net - Unit testing framework for C# and .NET (a successor to NUnit): xUnit.net 1.9.1: xUnit.net release 1.9.1Build #1600 Important note for Resharper users: Resharper support has been moved to the xUnit.net Contrib project. Important note for TestDriven.net users: If you are having issues running xUnit.net tests in TestDriven.net, especially on 64-bit Windows, we strongly recommend you upgrade to TD.NET version 3.0 or later. Important note for VS2012 users: The VS2012 runner is in the Visual Studio Gallery now, and should be installed via Tools | Extension Manager from insi...MVC Controls Toolkit: Mvc Controls Toolkit 2.2.0: Added Modified all Mv4 related features to conform with the Mvc4 RC Now all items controls accept any IEnumerable<T>(before just List<T> were accepted by most of controls) retrievalManager class that retrieves automatically data from a data source whenever it catchs events triggered by filtering, sorting, and paging controls move method to the updatesManager to move one child objects from a father to another. The move operation can be undone like the insert, update and delete operatio...IronPython: 2.7.3: On behalf of the IronPython team, I'm happy to announce the final release of IronPython 2.7.3. This release includes everything from IronPython 54498, 62475, and 74478 as well. Like all IronPython 2.7-series releases, .NET 4 is required to install it. Installing this release will replace any existing IronPython 2.7-series installation. The incompatibility with IronRuby has been resolved, and they can once again be installed side-by-side. The biggest improvements in IronPython 2.7.3 are: the...New ProjectsAuction Helper: Auction HelperBizTalk 0MQ Adapter: The BizTalk 0MQ Adapter allows BizTalk to send and receive messages using the ZeroMq cross platform messaging framework.fluentstatement: FluentStatement is a library for .NET usable to create Expressions Trees through its fluent interface. These ET can contain Lambda Expressions and Statements.Freemansoft: ??????????????????gppsoftware: gppsoftwarejAutoFitText - jQuery plug-in to auto-fit text similar to iOS applications: This is a jQuery plug-in that automatically fits text in a specific container using font size manipulation and/or string truncation. The end result is simjDelayedAction - jQuery plug-in to allow a delayed reaction to an event: This is a jQuery plug-in that allows the creation of an event (or multiple event) handler with a delay that can be extended or canceled before reacting.jInMemoryImageLoader - jQuery plug-in to asynchronously load an image: This is a jQuery plug-in that allows the asynchronous, in-memory loading of an image file with a callback for when it has succeeded or failed to load.jListSelect - jQuery plug-in for a fully customizable select input: A jQuery plug-in that allows you to create a fully customizable select input.jNumericalInput - jQuery plug-in to limit a text input to only numeric values: A simple jQuery plug-in that, when applied to an input of type text, only allows the input to have a numeric value (positive or negative).jVerticalAlignMiddle - jQuery plug-in to vertically align elements: A simple jQuery plug-in that vertically centers one element within its parent container.lhhp.net: this project is for testLiteCode: Your having enough of crackers, reverse engineers ? With LiteCode you can host your code remotely at a server where no cracker can touch itNetEx .net tool set: NetEx .net tool setOpenFlashChart: OpenFlashChart ??????Flash Chart??。 Project RPG: Developers learn how to design a game from the ground up.saka-pon.net: saka-pon.net.School System: Its all about school managementSeeForYourself: SeeForYourSelfSharepoint JQuery Editor Web Part: Enables quick JQuery development by executing your code immediately while in desing mode.Simplex: Simplex ???????????????J2EE???????????????。 Stuff.NET: This library provides several useful classes and methods to deal with frequently appearing challenges. e.g.: pathfinding, forms/controls, dynamic compiling, ...

  Read the article

• Django CMS - not able to upload images through cmsplugin_filer_image

  - by Luke

  i have a problem with a local installation on django cms 2.3.3: i've installed it trough pip, in a separated virtualenv. next i followed the tutorial for settings.py configuration, i started the server. Then in the admin i created an page (home), and i've tried to add an image in the placeholder through the cmsplugin_filer_image, but the upload seems that doesn't work. here's my settings.py: # Django settings for cms1 project. # -*- coding: utf-8 -*- import os gettext = lambda s: s PROJECT_PATH = os.path.abspath(os.path.dirname(__file__)) DEBUG = True TEMPLATE_DEBUG = DEBUG ADMINS = ( # ('Your Name', '[email protected]'), ) MANAGERS = ADMINS DATABASES = { 'default': { 'ENGINE': 'django.db.backends.postgresql_psycopg2', # Add 'postgresql_psycopg2', 'mysql', 'sqlite3' or 'oracle'. 'NAME': 'cms1', # Or path to database file if using sqlite3. 'USER': 'cms', # Not used with sqlite3. 'PASSWORD': 'cms', # Not used with sqlite3. 'HOST': '', # Set to empty string for localhost. Not used with sqlite3. 'PORT': '', # Set to empty string for default. Not used with sqlite3. } } # Local time zone for this installation. Choices can be found here: # http://en.wikipedia.org/wiki/List_of_tz_zones_by_name # although not all choices may be available on all operating systems. # In a Windows environment this must be set to your system time zone. TIME_ZONE = 'Europe/Rome' # Language code for this installation. All choices can be found here: # http://www.i18nguy.com/unicode/language-identifiers.html LANGUAGE_CODE = 'it-it' SITE_ID = 1 # If you set this to False, Django will make some optimizations so as not # to load the internationalization machinery. USE_I18N = True # If you set this to False, Django will not format dates, numbers and # calendars according to the current locale. USE_L10N = True # If you set this to False, Django will not use timezone-aware datetimes. USE_TZ = True # Absolute filesystem path to the directory that will hold user-uploaded files. # Example: "/home/media/media.lawrence.com/media/" MEDIA_ROOT = os.path.join(PROJECT_PATH, "media") # URL that handles the media served from MEDIA_ROOT. Make sure to use a # trailing slash. # Examples: "http://media.lawrence.com/media/", "http://example.com/media/" MEDIA_URL = '/media/' # Absolute path to the directory static files should be collected to. # Don't put anything in this directory yourself; store your static files # in apps' "static/" subdirectories and in STATICFILES_DIRS. # Example: "/home/media/media.lawrence.com/static/" STATIC_ROOT = os.path.join(PROJECT_PATH, "static") STATIC_URL = "/static/" # Additional locations of static files STATICFILES_DIRS = ( os.path.join(PROJECT_PATH, "static_auto"), # Put strings here, like "/home/html/static" or "C:/www/django/static". # Always use forward slashes, even on Windows. # Don't forget to use absolute paths, not relative paths. ) # List of finder classes that know how to find static files in # various locations. STATICFILES_FINDERS = ( 'django.contrib.staticfiles.finders.FileSystemFinder', 'django.contrib.staticfiles.finders.AppDirectoriesFinder', # 'django.contrib.staticfiles.finders.DefaultStorageFinder', ) # Make this unique, and don't share it with anybody. SECRET_KEY = '^c2q3d8w)f#gk%5i)(#i*lwt%lm-!2=(*1d!1cf+rg&amp;-hqi_9u' # List of callables that know how to import templates from various sources. TEMPLATE_LOADERS = ( 'django.template.loaders.filesystem.Loader', 'django.template.loaders.app_directories.Loader', # 'django.template.loaders.eggs.Loader', ) MIDDLEWARE_CLASSES = ( 'django.middleware.common.CommonMiddleware', 'django.contrib.sessions.middleware.SessionMiddleware', 'django.middleware.csrf.CsrfViewMiddleware', 'django.contrib.auth.middleware.AuthenticationMiddleware', 'django.contrib.messages.middleware.MessageMiddleware', 'cms.middleware.multilingual.MultilingualURLMiddleware', 'cms.middleware.page.CurrentPageMiddleware', 'cms.middleware.user.CurrentUserMiddleware', 'cms.middleware.toolbar.ToolbarMiddleware', # Uncomment the next line for simple clickjacking protection: # 'django.middleware.clickjacking.XFrameOptionsMiddleware', ) ROOT_URLCONF = 'cms1.urls' # Python dotted path to the WSGI application used by Django's runserver. WSGI_APPLICATION = 'cms1.wsgi.application' TEMPLATE_DIRS = ( os.path.join(PROJECT_PATH, "templates"), # Put strings here, like "/home/html/django_templates" or "C:/www/django/templates". # Always use forward slashes, even on Windows. # Don't forget to use absolute paths, not relative paths. ) CMS_TEMPLATES = ( ('template_1.html', 'Template One'), ('template_2.html', 'Template Two'), ) TEMPLATE_CONTEXT_PROCESSORS = ( 'django.contrib.auth.context_processors.auth', 'django.core.context_processors.i18n', 'django.core.context_processors.request', 'django.core.context_processors.media', 'django.core.context_processors.static', 'cms.context_processors.media', 'sekizai.context_processors.sekizai', ) LANGUAGES = [ ('it', 'Italiano'), ('en', 'English'), ] INSTALLED_APPS = ( 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.sites', 'django.contrib.messages', 'django.contrib.staticfiles', 'cms', #django CMS itself 'mptt', #utilities for implementing a modified pre-order traversal tree 'menus', #helper for model independent hierarchical website navigation 'south', #intelligent schema and data migrations 'sekizai', #for javascript and css management #'cms.plugins.file', 'cms.plugins.flash', 'cms.plugins.googlemap', 'cms.plugins.link', #'cms.plugins.picture', 'cms.plugins.snippet', 'cms.plugins.teaser', 'cms.plugins.text', #'cms.plugins.video', 'cms.plugins.twitter', 'filer', 'cmsplugin_filer_file', 'cmsplugin_filer_folder', 'cmsplugin_filer_image', 'cmsplugin_filer_teaser', 'cmsplugin_filer_video', 'easy_thumbnails', 'PIL', # Uncomment the next line to enable the admin: 'django.contrib.admin', # Uncomment the next line to enable admin documentation: # 'django.contrib.admindocs', ) # A sample logging configuration. The only tangible logging # performed by this configuration is to send an email to # the site admins on every HTTP 500 error when DEBUG=False. # See http://docs.djangoproject.com/en/dev/topics/logging for # more details on how to customize your logging configuration. LOGGING = { 'version': 1, 'disable_existing_loggers': False, 'filters': { 'require_debug_false': { '()': 'django.utils.log.RequireDebugFalse' } }, 'handlers': { 'mail_admins': { 'level': 'ERROR', 'filters': ['require_debug_false'], 'class': 'django.utils.log.AdminEmailHandler' } }, 'loggers': { 'django.request': { 'handlers': ['mail_admins'], 'level': 'ERROR', 'propagate': True, }, } } when i try to upload an image, in the clipboard section i don't have the thumbnail, but just an 'undefined' message: and this is the runserver console while trying to upload: [20/Oct/2012 15:15:56] "POST /admin/filer/clipboard/operations/upload/?qqfile=29708_1306856312320_7706073_n.jpg HTTP/1.1" 500 248133 [20/Oct/2012 15:15:56] "GET /it/admin/filer/folder/unfiled_images/undefined HTTP/1.1" 301 0 [20/Oct/2012 15:15:56] "GET /it/admin/filer/folder/unfiled_images/undefined/ HTTP/1.1" 404 1739 Also, this is project filesystem: cms1 +-- cms1 ¦   +-- __init__.py ¦   +-- __init__.pyc ¦   +-- media ¦   ¦   +-- filer_public ¦   ¦   +-- 2012 ¦   ¦   +-- 10 ¦   ¦   +-- 20 ¦   ¦   +-- 29708_1306856312320_7706073_n_1.jpg ¦   ¦   +-- 29708_1306856312320_7706073_n_2.jpg ¦   ¦   +-- 29708_1306856312320_7706073_n_3.jpg ¦   ¦   +-- 29708_1306856312320_7706073_n_4.jpg ¦   ¦   +-- 29708_1306856312320_7706073_n_5.jpg ¦   ¦   +-- 29708_1306856312320_7706073_n_6.jpg ¦   ¦   +-- 29708_1306856312320_7706073_n_7.jpg ¦   ¦   +-- 29708_1306856312320_7706073_n.jpg ¦   ¦   +-- torrent-client-macosx.jpg ¦   +-- settings.py ¦   +-- settings.pyc ¦   +-- static ¦   +-- static_auto ¦   +-- static_manual ¦   +-- templates ¦   ¦   +-- base.html ¦   ¦   +-- template_1.html ¦   ¦   +-- template_2.html ¦   +-- urls.py ¦   +-- urls.pyc ¦   +-- wsgi.py ¦   +-- wsgi.pyc +-- manage.py So files are uploaded, but they are not accessible to cms. there's a similar question here, but doens't help me so much. It would be very helpful any help on this issue to me. Thanks, luke

  Read the article

• What does Ruby have that Python doesn't, and vice versa?

  - by Lennart Regebro

  There is a lot of discussions of Python vs Ruby, and I all find them completely unhelpful, because they all turn around why feature X sucks in language Y, or that claim language Y doesn't have X, although in fact it does. I also know exactly why I prefer Python, but that's also subjective, and wouldn't help anybody choosing, as they might not have the same tastes in development as I do. It would therefore be interesting to list the differences, objectively. So no "Python's lambdas sucks". Instead explain what Ruby's lambdas can do that Python's can't. No subjectivity. Example code is good! Don't have several differences in one answer, please. And vote up the ones you know are correct, and down those you know are incorrect (or are subjective). Also, differences in syntax is not interesting. We know Python does with indentation what Ruby does with brackets and ends, and that @ is called self in Python. UPDATE: This is now a community wiki, so we can add the big differences here. Ruby has a class reference in the class body In Ruby you have a reference to the class (self) already in the class body. In Python you don't have a reference to the class until after the class construction is finished. An example: class Kaka puts self end self in this case is the class, and this code would print out "Kaka". There is no way to print out the class name or in other ways access the class from the class definition body in Python. All classes are mutable in Ruby This lets you develop extensions to core classes. Here's an example of a rails extension: class String def starts_with?(other) head = self[0, other.length] head == other end end Ruby has Perl-like scripting features Ruby has first class regexps, $-variables, the awk/perl line by line input loop and other features that make it more suited to writing small shell scripts that munge text files or act as glue code for other programs. Ruby has first class continuations Thanks to the callcc statement. In Python you can create continuations by various techniques, but there is no support built in to the language. Ruby has blocks With the "do" statement you can create a multi-line anonymous function in Ruby, which will be passed in as an argument into the method in front of do, and called from there. In Python you would instead do this either by passing a method or with generators. Ruby: amethod { |here| many=lines+of+code goes(here) } Python: def function(here): many=lines+of+code goes(here) amethod(function) Interestingly, the convenience statement in Ruby for calling a block is called "yield", which in Python will create a generator. Ruby: def themethod yield 5 end themethod do |foo| puts foo end Python: def themethod(): yield 5 for foo in themethod: print foo Although the principles are different, the result is strikingly similar. Python has built-in generators (which are used like Ruby blocks, as noted above) Python has support for generators in the language. In Ruby you could use the generator module that uses continuations to create a generator from a block. Or, you could just use a block/proc/lambda! Moreover, in Ruby 1.9 Fibers are, and can be used as, generators. docs.python.org has this generator example: def reverse(data): for index in range(len(data)-1, -1, -1): yield data[index] Contrast this with the above block examples. Python has flexible name space handling In Ruby, when you import a file with require, all the things defined in that file will end up in your global namespace. This causes namespace pollution. The solution to that is Rubys modules. But if you create a namespace with a module, then you have to use that namespace to access the contained classes. In Python, the file is a module, and you can import its contained names with from themodule import *, thereby polluting the namespace if you want. But you can also import just selected names with from themodule import aname, another or you can simply import themodule and then access the names with themodule.aname. If you want more levels in your namespace you can have packages, which are directories with modules and an __init__.py file. Python has docstrings Docstrings are strings that are attached to modules, functions and methods and can be introspected at runtime. This helps for creating such things as the help command and automatic documentation. def frobnicate(bar): """frobnicate takes a bar and frobnicates it >>> bar = Bar() >>> bar.is_frobnicated() False >>> frobnicate(bar) >>> bar.is_frobnicated() True """ Python has more libraries Python has a vast amount of available modules and bindings for libraries. Python has multiple inheritance Ruby does not ("on purpose" -- see Ruby's website, see here how it's done in Ruby). It does reuse the module concept as a sort of abstract classes. Python has list/dict comprehensions Python: res = [x*x for x in range(1, 10)] Ruby: res = (0..9).map { |x| x * x } Python: >>> (x*x for x in range(10)) <generator object <genexpr> at 0xb7c1ccd4> >>> list(_) [0, 1, 4, 9, 16, 25, 36, 49, 64, 81] Ruby: p = proc { |x| x * x } (0..9).map(&p) Python: >>> {x:str(y*y) for x,y in {1:2, 3:4}.items()} {1: '4', 3: '16'} Ruby: >> Hash[{1=>2, 3=>4}.map{|x,y| [x,(y*y).to_s]}] => {1=>"4", 3=>"16"} Python has decorators Things similar to decorators can be created in Ruby, and it can also be argued that they aren't as necessary as in Python.

  Read the article

• Java style FOR loop in a clojure interpeter ?

  - by Kevin

  I have a basic interpreter in clojure. Now i need to implement for (initialisation; finish-test; loop-update) { statements } inside my interpreter. I will attach my interpreter code I got so far. Any help is appreciated. Interpreter (declare interpret make-env) ;; (def do-trace false) ;; ;; simple utilities (def third ; return third item in a list (fn [a-list] (second (rest a-list)))) (def fourth ; return fourth item in a list (fn [a-list] (third (rest a-list)))) (def run ; make it easy to test the interpreter (fn [e] (println "Processing: " e) (println "=> " (interpret e (make-env))))) ;; for the environment (def make-env (fn [] '())) (def add-var (fn [env var val] (cons (list var val) env))) (def lookup-var (fn [env var] (cond (empty? env) 'error (= (first (first env)) var) (second (first env)) :else (lookup-var (rest env) var)))) ;; -- define numbers (def is-number? (fn [expn] (number? expn))) (def interpret-number (fn [expn env] expn)) ;; -- define symbols (def is-symbol? (fn [expn] (symbol? expn))) (def interpret-symbol (fn [expn env] (lookup-var env expn))) ;; -- define boolean (def is-boolean? (fn [expn] (or (= expn 'true) (= expn 'false)))) (def interpret-boolean (fn [expn env] expn)) ;; -- define functions (def is-function? (fn [expn] (and (list? expn) (= 3 (count expn)) (= 'lambda (first expn))))) (def interpret-function (fn [expn env] expn)) ;; -- define addition (def is-plus? (fn [expn] (and (list? expn) (= 3 (count expn)) (= '+ (first expn))))) (def interpret-plus (fn [expn env] (+ (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define subtraction (def is-minus? (fn [expn] (and (list? expn) (= 3 (count expn)) (= '- (first expn))))) (def interpret-minus (fn [expn env] (- (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define multiplication (def is-times? (fn [expn] (and (list? expn) (= 3 (count expn)) (= '* (first expn))))) (def interpret-times (fn [expn env] (* (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define division (def is-divides? (fn [expn] (and (list? expn) (= 3 (count expn)) (= '/ (first expn))))) (def interpret-divides (fn [expn env] (/ (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define equals test (def is-equals? (fn [expn] (and (list? expn) (= 3 (count expn)) (= '= (first expn))))) (def interpret-equals (fn [expn env] (= (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define greater-than test (def is-greater-than? (fn [expn] (and (list? expn) (= 3 (count expn)) (= '> (first expn))))) (def interpret-greater-than (fn [expn env] (> (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define not (def is-not? (fn [expn] (and (list? expn) (= 2 (count expn)) (= 'not (first expn))))) (def interpret-not (fn [expn env] (not (interpret (second expn) env)))) ;; -- define or (def is-or? (fn [expn] (and (list? expn) (= 3 (count expn)) (= 'or (first expn))))) (def interpret-or (fn [expn env] (or (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define and (def is-and? (fn [expn] (and (list? expn) (= 3 (count expn)) (= 'and (first expn))))) (def interpret-and (fn [expn env] (and (interpret (second expn) env) (interpret (third expn) env)))) ;; -- define with (def is-with? (fn [expn] (and (list? expn) (= 3 (count expn)) (= 'with (first expn))))) (def interpret-with (fn [expn env] (interpret (third expn) (add-var env (first (second expn)) (interpret (second (second expn)) env))))) ;; -- define if (def is-if? (fn [expn] (and (list? expn) (= 4 (count expn)) (= 'if (first expn))))) (def interpret-if (fn [expn env] (cond (interpret (second expn) env) (interpret (third expn) env) :else (interpret (fourth expn) env)))) ;; -- define function-application (def is-function-application? (fn [expn env] (and (list? expn) (= 2 (count expn)) (is-function? (interpret (first expn) env))))) (def interpret-function-application (fn [expn env] (let [function (interpret (first expn) env)] (interpret (third function) (add-var env (first (second function)) (interpret (second expn) env)))))) ;; the interpreter itself (def interpret (fn [expn env] (cond do-trace (println "Interpret is processing: " expn)) (cond ; basic values (is-number? expn) (interpret-number expn env) (is-symbol? expn) (interpret-symbol expn env) (is-boolean? expn) (interpret-boolean expn env) (is-function? expn) (interpret-function expn env) ; built-in functions (is-plus? expn) (interpret-plus expn env) (is-minus? expn) (interpret-minus expn env) (is-times? expn) (interpret-times expn env) (is-divides? expn) (interpret-divides expn env) (is-equals? expn) (interpret-equals expn env) (is-greater-than? expn) (interpret-greater-than expn env) (is-not? expn) (interpret-not expn env) (is-or? expn) (interpret-or expn env) (is-and? expn) (interpret-and expn env) ; special syntax (is-with? expn) (interpret-with expn env) (is-if? expn) (interpret-if expn env) ; functions (is-function-application? expn env) (interpret-function-application expn env) :else 'error)))

  Read the article

• iPhone SDK vs. Windows Phone 7 Series SDK Challenge, Part 2: MoveMe

  In this series, I will be taking sample applications from the iPhone SDK and implementing them on Windows Phone 7 Series.  My goal is to do as much of an apples-to-apples comparison as I can.  This series will be written to not only compare and contrast how easy or difficult it is to complete tasks on either platform, how many lines of code, etc., but Id also like it to be a way for iPhone developers to either get started on Windows Phone 7 Series development, or for developers in general to learn the platform. Heres my methodology: Run the iPhone SDK app in the iPhone Simulator to get a feel for what it does and how it works, without looking at the implementation Implement the equivalent functionality on Windows Phone 7 Series using Silverlight. Compare the two implementations based on complexity, functionality, lines of code, number of files, etc. Add some functionality to the Windows Phone 7 Series app that shows off a way to make the scenario more interesting or leverages an aspect of the platform, or uses a better design pattern to implement the functionality. You can download Microsoft Visual Studio 2010 Express for Windows Phone CTP here, and the Expression Blend 4 Beta here. If youre seeing this series for the first time, check out Part 1: Hello World. A note on methodologyin the prior post there was some feedback about lines of code not being a very good metric for this exercise.  I dont really disagree, theres a lot more to this than lines of code but I believe that is a relevant metric, even if its not the ultimate one.  And theres no perfect answer here.  So I am going to continue to report the number of lines of code that I, as a developer would need to write in these apps as a data point, and Ill leave it up to the reader to determine how that fits in with overall complexity, etc.  The first example was so basic that I think it was difficult to talk about in real terms.  I think that as these apps get more complex, the subjective differences in concept count and will be more important.  MoveMe The MoveMe app is the main end-to-end app writing example in the iPhone SDK, called Creating an iPhone Application.  This application demonstrates a few concepts, including handling touch input, how to do animations, and how to do some basic transforms. The behavior of the application is pretty simple.  User touches the button: The button does a throb type animation where it scales up and then back down briefly. User drags the button: After a touch begins, moving the touch point will drag the button around with the touch. User lets go of the button: The button animates back to its original position, but does a few small bounces as it reaches its original point, which makes the app fun and gives it an extra bit of interactivity. Now, how would I write an app that meets this spec for Windows Phone 7 Series, and how hard would it be?  Lets find out!     Implementing the UI Okay, lets build the UI for this application.  In the HelloWorld example, we did all the UI design in Visual Studio and/or by hand in XAML.  In this example, were going to use the Expression Blend 4 Beta. You might be wondering when to use Visual Studio, when to use Blend, and when to do XAML by hand.  Different people will have different takes on this, but heres mine: XAML by hand simple UI that doesnt contain animations, gradients, etc., and or UI that I want to really optimize and craft when I know exactly what I want to do. Visual Studio Basic UI layout, property setting, data binding, etc. Blend Any serious design work needs to be done in Blend, including animations, handling states and transitions, styling and templating, editing resources. As in Part 1, go ahead and fire up Visual Studio 2010 Express for Windows Phone (yes, soon it will take longer to say the name of our products than to start them up!), and create a new Windows Phone Application.  As in Part 1, clear out the XAML from the designer.  An easy way to do this is to just: Click on the design surface Hit Control+A Hit Delete Theres a little bit left over (the Grid.RowDefinitions element), just go ahead and delete that element so were starting with a clean state of only one outer Grid element. To use Blend, we need to save this project.  See, when you create a project with Visual Studio Express, it doesnt commit it to the disk (well, in a place where you can find it, at least) until you actually save the project.  This is handy if youre doing some fooling around, because it doesnt clutter your disk with WindowsPhoneApplication23-like directories.  But its also kind of dangerous, since when you close VS, if you dont save the projectits all gone.  Yes, this has bitten me since I was saving files and didnt remember that, so be careful to save the project/solution via Save All, at least once. So, save and note the location on disk.  Start Expression Blend 4 Beta, and chose File > Open Project/Solution, and load your project.  You should see just about the same thing you saw over in VS: a blank, black designer surface. Now, thinking about this application, we dont really need a button, even though it looks like one.  We never click it.  So were just going to create a visual and use that.  This is also true in the iPhone example above, where the visual is actually not a button either but a jpg image with a nice gradient and round edges.  Well do something simple here that looks pretty good. In Blend, look in the tool pane on the left for the icon that looks like the below (the highlighted one on the left), and hold it down to get the popout menu, and choose Border:    Okay, now draw out a box in the middle of the design surface of about 300x100.  The Properties Pane to the left should show the properties for this item. First, lets make it more visible by giving it a border brush.  Set the BorderBrush to white by clicking BorderBrush and dragging the color selector all the way to the upper right in the palette.  Then, down a bit farther, make the BorderThickness 4 all the way around, and the CornerRadius set to 6. In the Layout section, do the following to Width, Height, Horizontal and Vertical Alignment, and Margin (all 4 margin values): Youll see the outline now is in the middle of the design surface.  Now lets give it a background color.  Above BorderBrush select Background, and click the third tab over: Gradient Brush.  Youll see a gradient slider at the bottom, and if you click the markers, you can edit the gradient stops individually (or add more).  In this case, you can select something you like, but wheres what I chose: Left stop: #BFACCFE2 (I just picked a spot on the palette and set opacity to 75%, no magic here, feel free to fiddle these or just enter these numbers into the hex area and be done with it) Right stop: #FF3E738F Okay, looks pretty good.  Finally set the name of the element in the Name field at the top of the Properties pane to welcome. Now lets add some text.  Just hit T and itll select the TextBlock tool automatically: Now draw out some are inside our welcome visual and type Welcome!, then click on the design surface (to exit text entry mode) and hit V to go back into selection mode (or the top item in the tool pane that looks like a mouse pointer).  Click on the text again to select it in the tool pane.  Just like the border, we want to center this.  So set HorizontalAlignment and VerticalAlignment to Center, and clear the Margins: Thats it for the UI.  Heres how it looks, on the design surface: Not bad!  Okay, now the fun part Adding Animations Using Blend to build animations is a lot of fun, and its easy.  In XAML, I can not only declare elements and visuals, but also I can declare animations that will affect those visuals.  These are called Storyboards. To recap, well be doing two animations: The throb animation when the element is touched The center animation when the element is released after being dragged. The throb animation is just a scale transform, so well do that first.  In the Objects and Timeline Pane (left side, bottom half), click the little + icon to add a new Storyboard called touchStoryboard: The timeline view will appear.  In there, click a bit to the right of 0 to create a keyframe at .2 seconds: Now, click on our welcome element (the Border, not the TextBlock in it), and scroll to the bottom of the Properties Pane.  Open up Transform, click the third tab ("Scale), and set X and Y to 1.2: This all of this says that, at .2 seconds, I want the X and Y size of this element to scale to 1.2. In fact you can see this happen.  Push the Play arrow in the timeline view, and youll see the animation run! Lets make two tweaks.  First, we want the animation to automatically reverse so it scales up then back down nicely. Click in the dropdown that says touchStoryboard in Objects and Timeline, then in the Properties pane check Auto Reverse: Now run it again, and youll see it go both ways. Lets even make it nicer by adding an easing function. First, click on the Render Transform item in the Objects tree, then, in the Property Pane, youll see a bunch of easing functions to choose from.  Feel free to play with this, then seeing how each runs.  I chose Circle In, but some other ones are fun.  Try them out!  Elastic In is kind of fun, but well stick with Circle In.  Thats it for that animation. Now, we also want an animation to move the Border back to its original position when the user ends the touch gesture.  This is exactly the same process as above, but just targeting a different transform property. Create a new animation called releaseStoryboard Select a timeline point at 1.2 seconds. Click on the welcome Border element again Scroll to the Transforms panel at the bottom of the Properties Pane Choose the first tab (Translate), which may already be selected Set both X and Y values to 0.0 (we do this just to make the values stick, because the value is already 0 and we need Blend to know we want to save that value) Click on RenderTransform in the Objects tree In the properties pane, choose Bounce Out Set Bounces to 6, and Bounciness to 4 (feel free to play with these as well) Okay, were done. Note, if you want to test this Storyboard, you have to do something a little tricky because the final value is the same as the initial value, so playing it does nothing.  If you want to play with it, do the following: Next to the selection dropdown, hit the little "x (Close Storyboard) Go to the Translate Transform value for welcome Set X,Y to 50, 200, respectively (or whatever) Select releaseStoryboard again from the dropdown Hit play, see it run Go into the object tree and select RenderTransform to change the easing function. When youre done, hit the Close Storyboard x again and set the values in Transform/Translate back to 0 Wiring Up the Animations Okay, now go back to Visual Studio.  Youll get a prompt due to the modification of MainPage.xaml.  Hit Yes. In the designer, click on the welcome Border element.  In the Property Browser, hit the Events button, then double click each of ManipulationStarted, ManipulationDelta, ManipulationCompleted.  Youll need to flip back to the designer from code, after each double click. Its code time.  Here we go. Here, three event handlers have been created for us: welcome_ManipulationStarted: This will execute when a manipulation begins.  Think of it as MouseDown. welcome_ManipulationDelta: This executes each time a manipulation changes.  Think MouseMove. welcome_ManipulationCompleted: This will  execute when the manipulation ends. Think MouseUp. Now, in ManipuliationStarted, we want to kick off the throb animation that we called touchAnimation.  Thats easy: 1: private void welcome_ManipulationStarted(object sender, ManipulationStartedEventArgs e) 2: { 3: touchStoryboard.Begin(); 4: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Likewise, when the manipulation completes, we want to re-center the welcome visual with our bounce animation: 1: private void welcome_ManipulationCompleted(object sender, ManipulationCompletedEventArgs e) 2: { 3: releaseStoryboard.Begin(); 4: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Note there is actually a way to kick off these animations from Blend directly via something called Triggers, but I think its clearer to show whats going on like this.  A Trigger basically allows you to say When this event fires, trigger this Storyboard, so its the exact same logical process as above, but without the code. But how do we get the object to move?  Well, for that we really dont want an animation because we want it to respond immediately to user input. We do this by directly modifying the transform to match the offset for the manipulation, and then well let the animation bring it back to zero when the manipulation completes.  The manipulation events do a great job of keeping track of all the stuff that you usually had to do yourself when doing drags: where you started from, how far youve moved, etc. So we can easily modify the position as below: 1: private void welcome_ManipulationDelta(object sender, ManipulationDeltaEventArgs e) 2: { 3: CompositeTransform transform = (CompositeTransform)welcome.RenderTransform; 4:   5: transform.TranslateX = e.CumulativeManipulation.Translation.X; 6: transform.TranslateY = e.CumulativeManipulation.Translation.Y; 7: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Thats it! Go ahead and run the app in the emulator.  I suggest running without the debugger, its a little faster (CTRL+F5).  If youve got a machine that supports DirectX 10, youll see nice smooth GPU accelerated graphics, which also what it looks like on the phone, running at about 60 frames per second.  If your machine does not support DX10 (like the laptop Im writing this on!), it wont be quite a smooth so youll have to take my word for it! Comparing Against the iPhone This is an example where the flexibility and power of XAML meets the tooling of Visual Studio and Blend, and the whole experience really shines.  So, for several things that are declarative and 100% toolable with the Windows Phone 7 Series, this example does them with code on the iPhone.  In parens is the lines of code that I count to do these operations. PlacardView.m: 19 total LOC Creating the view that hosts the button-like image and the text Drawing the image that is the background of the button Drawing the Welcome text over the image (I think you could technically do this step and/or the prior one using Interface Builder) MoveMeView.m:  63 total LOC Constructing and running the scale (throb) animation (25) Constructing the path describing the animation back to center plus bounce effect (38) Beyond the code count, yy experience with doing this kind of thing in code is that its VERY time intensive.  When I was a developer back on Windows Forms, doing GDI+ drawing, we did this stuff a lot, and it took forever!  You write some code and even once you get it basically working, you see its not quite right, you go back, tweak the interval, or the math a bit, run it again, etc.  You can take a look at the iPhone code here to judge for yourself.  Scroll down to animatePlacardViewToCenter toward the bottom.  I dont think this code is terribly complicated, but its not what Id call simple and its not at all simple to get right. And then theres a few other lines of code running around for setting up the ViewController and the Views, about 15 lines between MoveMeAppDelegate, PlacardView, and MoveMeView, plus the assorted decls in the h files. Adding those up, I conservatively get something like 100 lines of code (19+63+15+decls) on iPhone that I have to write, by hand, to make this project work. The lines of code that I wrote in the examples above is 5 lines of code on Windows Phone 7 Series. In terms of incremental concept counts beyond the HelloWorld app, heres a shot at that: iPhone: Drawing Images Drawing Text Handling touch events Creating animations Scaling animations Building a path and animating along that Windows Phone 7 Series: Laying out UI in Blend Creating & testing basic animations in Blend Handling touch events Invoking animations from code This was actually the first example I tried converting, even before I did the HelloWorld, and I was pretty surprised.  Some of this is luck that this app happens to match up with the Windows Phone 7 Series platform just perfectly.  In terms of time, I wrote the above application, from scratch, in about 10 minutes.  I dont know how long it would take a very skilled iPhone developer to write MoveMe on that iPhone from scratch, but if I was to write it on Silverlight in the same way (e.g. all via code), I think it would likely take me at least an hour or two to get it all working right, maybe more if I ended up picking the wrong strategy or couldnt get the math right, etc. Making Some Tweaks Silverlight contains a feature called Projections to do a variety of 3D-like effects with a 2D surface. So lets play with that a bit. Go back to Blend and select the welcome Border in the object tree.  In its properties, scroll down to the bottom, open Transform, and see Projection at the bottom.  Set X,Y,Z to 90.  Youll see the element kind of disappear, replaced by a thin blue line. Now Create a new animation called startupStoryboard. Set its key time to .5 seconds in the timeline view Set the projection values above to 0 for X, Y, and Z. Save Go back to Visual Studio, and in the constructor, add the following bold code (lines 7-9 to the constructor: 1: public MainPage() 2: { 3: InitializeComponent(); 4:   5: SupportedOrientations = SupportedPageOrientation.Portrait; 6:   7: this.Loaded += (s, e) => 8: { 9: startupStoryboard.Begin(); 10: }; 11: } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } If the code above looks funny, its using something called a lambda in C#, which is an inline anonymous method.  Its just a handy shorthand for creating a handler like the manipulation ones above. So with this youll get a nice 3D looking fly in effect when the app starts up.  Here it is, in flight: Pretty cool!Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

  Read the article

• Java Errors with jRuby on Rails on Google App Engine

  - by John Wang

  I followed all of the instructions so far from: http://code.google.com/p/appengine-jruby/wiki/RunningRails and http://gist.github.com/268192 Currently, I'm just trying to get to hello world. I'm getting these errors when I just run the dev_appserver.rb 238:hello-world jwang392$ dev_appserver.rb . => Booting DevAppServer => Press Ctrl-C to shutdown server => Generating configuration files 2010-04-08 09:16:51.961 java[411:1707] [Java CocoaComponent compatibility mode]: Enabled 2010-04-08 09:16:51.964 java[411:1707] [Java CocoaComponent compatibility mode]: Setting timeout for SWT to 0.100000 Apr 8, 2010 7:17:05 PM com.google.appengine.tools.development.ApiProxyLocalImpl log SEVERE: [1270754225387000] javax.servlet.ServletContext log: Warning: error application could not be initialized org.jruby.rack.RackInitializationException: no such file to load -- time from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25:in `boot!' from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/boot/rack.rb:10 from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1:in `load' from <script>:1 at org.jruby.rack.DefaultRackApplicationFactory $4.init(DefaultRackApplicationFactory.java:169) at org.jruby.rack.DefaultRackApplicationFactory.newErrorApplication(DefaultRac kApplicationFactory.java: 118) at org.jruby.rack.DefaultRackApplicationFactory.init(DefaultRackApplicationFac tory.java: 37) at org.jruby.rack.SharedRackApplicationFactory.init(SharedRackApplicationFacto ry.java: 26) at org.jruby.rack.RackServletContextListener.contextInitialized(RackServletCon textListener.java: 40) at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java: 530) at org.mortbay.jetty.servlet.Context.startContext(Context.java:135) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java: 1218) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java: 500) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java: 448) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java: 117) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java: 117) at org.mortbay.jetty.Server.doStart(Server.java:217) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at com.google.appengine.tools.development.JettyContainerService.startContainer (JettyContainerService.java: 188) at com.google.appengine.tools.development.AbstractContainerService.startup(Abs tractContainerService.java: 147) at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerI mpl.java: 219) at com.google.appengine.tools.development.DevAppServerMain $StartAction.apply(DevAppServerMain.java:162) at com.google.appengine.tools.util.Parser $ParseResult.applyArgs(Parser.java:48) at com.google.appengine.tools.development.DevAppServerMain.<init>(DevAppServer Main.java: 113) at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMa in.java: 89) Caused by: org.jruby.exceptions.RaiseException: no such file to load -- time at (unknown).new(file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25) at Kernel.require(file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25) at JRuby::Rack::Booter.boot!(file:/Users/jwang392/hello-world/WEB-INF/ lib/jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:10) at (unknown).(unknown)(file:/Users/jwang392/hello-world/WEB-INF/lib/ jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1) at (unknown).(unknown)(file:/Users/jwang392/Dhello-world/WEB-INF/lib/ jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1) at Kernel.load(<script>:1) at (unknown).(unknown)(:1) Apr 8, 2010 7:17:05 PM com.google.appengine.tools.development.ApiProxyLocalImpl log SEVERE: [1270754225913000] javax.servlet.ServletContext log: unable to create shared application instance org.jruby.rack.RackInitializationException: no such file to load -- time from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25:in `boot!' from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/boot/rack.rb:10 from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1:in `load' from <script>:1 at org.jruby.rack.DefaultRackApplicationFactory $4.init(DefaultRackApplicationFactory.java:169) at org.jruby.rack.DefaultRackApplicationFactory.getApplication(DefaultRackAppl icationFactory.java: 51) at org.jruby.rack.SharedRackApplicationFactory.init(SharedRackApplicationFacto ry.java: 27) at org.jruby.rack.RackServletContextListener.contextInitialized(RackServletCon textListener.java: 40) at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java: 530) at org.mortbay.jetty.servlet.Context.startContext(Context.java:135) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java: 1218) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java: 500) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java: 448) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java: 117) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java: 117) at org.mortbay.jetty.Server.doStart(Server.java:217) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at com.google.appengine.tools.development.JettyContainerService.startContainer (JettyContainerService.java: 188) at com.google.appengine.tools.development.AbstractContainerService.startup(Abs tractContainerService.java: 147) at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerI mpl.java: 219) at com.google.appengine.tools.development.DevAppServerMain $StartAction.apply(DevAppServerMain.java:162) at com.google.appengine.tools.util.Parser $ParseResult.applyArgs(Parser.java:48) at com.google.appengine.tools.development.DevAppServerMain.<init>(DevAppServer Main.java: 113) at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMa in.java: 89) Caused by: org.jruby.exceptions.RaiseException: no such file to load -- time at (unknown).new(file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25) at Kernel.require(file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25) at JRuby::Rack::Booter.boot!(file:/Users/jwang392/hello-world/WEB-INF/ lib/jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:10) at (unknown).(unknown)(file:/Users/jwang392/hello-world/WEB-INF/lib/ jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1) at (unknown).(unknown)(file:/Users/jwang392/hello-world/WEB-INF/lib/ jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1) at Kernel.load(<script>:1) at (unknown).(unknown)(:1) Apr 8, 2010 7:17:05 PM com.google.appengine.tools.development.ApiProxyLocalImpl log SEVERE: [1270754225915000] javax.servlet.ServletContext log: Error: application initialization failed org.jruby.rack.RackInitializationException: unable to create shared application instance at org.jruby.rack.SharedRackApplicationFactory.init(SharedRackApplicationFacto ry.java: 39) at org.jruby.rack.RackServletContextListener.contextInitialized(RackServletCon textListener.java: 40) at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java: 530) at org.mortbay.jetty.servlet.Context.startContext(Context.java:135) at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java: 1218) at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java: 500) at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java: 448) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java: 117) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java: 117) at org.mortbay.jetty.Server.doStart(Server.java:217) at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java: 40) at com.google.appengine.tools.development.JettyContainerService.startContainer (JettyContainerService.java: 188) at com.google.appengine.tools.development.AbstractContainerService.startup(Abs tractContainerService.java: 147) at com.google.appengine.tools.development.DevAppServerImpl.start(DevAppServerI mpl.java: 219) at com.google.appengine.tools.development.DevAppServerMain $StartAction.apply(DevAppServerMain.java:162) at com.google.appengine.tools.util.Parser $ParseResult.applyArgs(Parser.java:48) at com.google.appengine.tools.development.DevAppServerMain.<init>(DevAppServer Main.java: 113) at com.google.appengine.tools.development.DevAppServerMain.main(DevAppServerMa in.java: 89) Caused by: org.jruby.rack.RackInitializationException: no such file to load -- time from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25:in `boot!' from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/boot/rack.rb:10 from file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1:in `load' from <script>:1 at org.jruby.rack.DefaultRackApplicationFactory $4.init(DefaultRackApplicationFactory.java:169) at org.jruby.rack.DefaultRackApplicationFactory.getApplication(DefaultRackAppl icationFactory.java: 51) at org.jruby.rack.SharedRackApplicationFactory.init(SharedRackApplicationFacto ry.java: 27) ... 19 more Caused by: org.jruby.exceptions.RaiseException: no such file to load -- time at (unknown).new(file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25) at Kernel.require(file:/Users/jwang392/hello-world/WEB-INF/lib/jruby- rack-0.9.6.jar!/jruby/rack/booter.rb:25) at JRuby::Rack::Booter.boot!(file:/Users/jwang392/hello-world/WEB-INF/ lib/jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:10) at (unknown).(unknown)(file:/Users/jwang392/hello-world/WEB-INF/lib/ jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1) at (unknown).(unknown)(file:/Users/jwang392/hello-world/WEB-INF/lib/ jruby-rack-0.9.6.jar!/jruby/rack/boot/rack.rb:1) at Kernel.load(<script>:1) at (unknown).(unknown)(:1) The server is running at http://localhost:8080/ I'm at a loss at what step I may have missed. I checked my ruby version (1.8.7) and rails version (2.3.5), gem version (1.3.6) and google-appengine-0.0.10.1 ran: sudo gem install google-appengine curl -O http://appengine-jruby.googlecode.com/hg/demos/rails2/rails2_appengine.rb ruby rails2_appengine.rb sudo gem install rails_dm_datastore sudo gem install activerecord-nulldb-adapter put this in my config.ru file: run lambda { |env| Rack::Response.new('Hello World!').finish } and finally ran $ dev_appserver.rb .

  Read the article

• scrolling lags in emacs 23.2 with GTK

  - by mefiX

  Hey there, I am using emacs 23.2 with the GTK toolkit. I built emacs from source using the following configure-params: ./configure --prefix=/usr --without-makeinfo --without-sound Which builds emacs with the following configuration: Where should the build process find the source code? /home/****/incoming/emacs-23.2 What operating system and machine description files should Emacs use? `s/gnu-linux.h' and `m/intel386.h' What compiler should emacs be built with? gcc -g -O2 -Wdeclaration-after-statement -Wno-pointer-sign Should Emacs use the GNU version of malloc? yes (Using Doug Lea's new malloc from the GNU C Library.) Should Emacs use a relocating allocator for buffers? yes Should Emacs use mmap(2) for buffer allocation? no What window system should Emacs use? x11 What toolkit should Emacs use? GTK Where do we find X Windows header files? Standard dirs Where do we find X Windows libraries? Standard dirs Does Emacs use -lXaw3d? no Does Emacs use -lXpm? yes Does Emacs use -ljpeg? yes Does Emacs use -ltiff? yes Does Emacs use a gif library? yes -lgif Does Emacs use -lpng? yes Does Emacs use -lrsvg-2? no Does Emacs use -lgpm? yes Does Emacs use -ldbus? yes Does Emacs use -lgconf? no Does Emacs use -lfreetype? yes Does Emacs use -lm17n-flt? no Does Emacs use -lotf? yes Does Emacs use -lxft? yes Does Emacs use toolkit scroll bars? yes When I'm scrolling within files of a common size (about 1000 lines) holding the up/down-keys, emacs almost hangs and produces about 50% CPU-load. I use the following plugins: ido linum tabbar auto-complete-config Starting emacs with -q fixes the problem, but then I don't have any plugins. I can't figure out, which part of my .emacs is responsible for this behaviour. Here's an excerpt of my .emacs-file: (require 'ido) (ido-mode 1) (require 'linum) (global-linum-mode 1) (require 'tabbar) (tabbar-mode 1) (tabbar-local-mode 0) (tabbar-mwheel-mode 0) (setq tabbar-buffer-groups-function (lambda () (list "All"))) (global-set-key [M-left] 'tabbar-backward) (global-set-key [M-right] 'tabbar-forward) ;; hide the toolbar (gtk etc.) (tool-bar-mode -1) ;; Mouse scrolling enhancements (setq mouse-wheel-progressive-speed nil) (setq mouse-wheel-scroll-amount '(5 ((shift) . 5) ((control) . nil))) ;; Smart-HOME (defun smart-beginning-of-line () "Forces the cursor to jump to the first none whitespace char of the current line when pressing HOME" (interactive) (let ((oldpos (point))) (back-to-indentation) (and (= oldpos (point)) (beginning-of-line)))) (put 'smart-beginning-of-line 'CUA 'move) (global-set-key [home] 'smart-beginning-of-line) (custom-set-variables ;; custom-set-variables was added by Custom. ;; If you edit it by hand, you could mess it up, so be careful. ;; Your init file should contain only one such instance. ;; If there is more than one, they won't work right. '(column-number-mode t) '(cua-mode t nil (cua-base)) '(custom-buffer-indent 4) '(delete-selection-mode nil) '(display-time-24hr-format t) '(display-time-day-and-date 1) '(display-time-mode t) '(global-font-lock-mode t nil (font-lock)) '(inhibit-startup-buffer-menu t) '(inhibit-startup-screen t) '(pc-select-meta-moves-sexps t) '(pc-select-selection-keys-only t) '(pc-selection-mode t nil (pc-select)) '(scroll-bar-mode (quote right)) '(show-paren-mode t) '(standard-indent 4) '(uniquify-buffer-name-style (quote forward) nil (uniquify))) (setq-default tab-width 4) (setq-default indent-tabs-mode t) (setq c-basic-offset 4) ;; Highlighting of the current line (global-hl-line-mode 1) (set-face-background 'hl-line "#E8F2FE") (defalias 'yes-or-no-p 'y-or-n-p) (display-time) (set-language-environment "Latin-1") ;; Change cursor color according to mode (setq djcb-read-only-color "gray") ;; valid values are t, nil, box, hollow, bar, (bar . WIDTH), hbar, ;; (hbar. HEIGHT); see the docs for set-cursor-type (setq djcb-read-only-cursor-type 'hbar) (setq djcb-overwrite-color "red") (setq djcb-overwrite-cursor-type 'box) (setq djcb-normal-color "black") (setq djcb-normal-cursor-type 'bar) (defun djcb-set-cursor-according-to-mode () "change cursor color and type according to some minor modes." (cond (buffer-read-only (set-cursor-color djcb-read-only-color) (setq cursor-type djcb-read-only-cursor-type)) (overwrite-mode (set-cursor-color djcb-overwrite-color) (setq cursor-type djcb-overwrite-cursor-type)) (t (set-cursor-color djcb-normal-color) (setq cursor-type djcb-normal-cursor-type)))) (add-hook 'post-command-hook 'djcb-set-cursor-according-to-mode) (define-key global-map '[C-right] 'forward-sexp) (define-key global-map '[C-left] 'backward-sexp) (define-key global-map '[s-left] 'windmove-left) (define-key global-map '[s-right] 'windmove-right) (define-key global-map '[s-up] 'windmove-up) (define-key global-map '[s-down] 'windmove-down) (define-key global-map '[S-down-mouse-1] 'mouse-stay-and-copy) (define-key global-map '[C-M-S-down-mouse-1] 'mouse-stay-and-swap) (define-key global-map '[S-mouse-2] 'mouse-yank-and-kill) (define-key global-map '[C-S-down-mouse-1] 'mouse-stay-and-kill) (define-key global-map "\C-a" 'mark-whole-buffer) (custom-set-faces ;; custom-set-faces was added by Custom. ;; If you edit it by hand, you could mess it up, so be careful. ;; Your init file should contain only one such instance. ;; If there is more than one, they won't work right. '(default ((t (:inherit nil :stipple nil :background "#f7f9fa" :foreground "#191919" :inverse-video nil :box nil :strike-through nil :overline nil :underline nil :slant normal :weight normal :height 98 :width normal :foundry "unknown" :family "DejaVu Sans Mono")))) '(font-lock-builtin-face ((((class color) (min-colors 88) (background light)) (:foreground "#642880" :weight bold)))) '(font-lock-comment-face ((((class color) (min-colors 88) (background light)) (:foreground "#3f7f5f")))) '(font-lock-constant-face ((((class color) (min-colors 88) (background light)) (:weight bold)))) '(font-lock-doc-face ((t (:inherit font-lock-string-face :foreground "#3f7f5f")))) '(font-lock-function-name-face ((((class color) (min-colors 88) (background light)) (:foreground "Black" :weight bold)))) '(font-lock-keyword-face ((((class color) (min-colors 88) (background light)) (:foreground "#7f0055" :weight bold)))) '(font-lock-preprocessor-face ((t (:inherit font-lock-builtin-face :foreground "#7f0055" :weight bold)))) '(font-lock-string-face ((((class color) (min-colors 88) (background light)) (:foreground "#0000c0")))) '(font-lock-type-face ((((class color) (min-colors 88) (background light)) (:foreground "#7f0055" :weight bold)))) '(font-lock-variable-name-face ((((class color) (min-colors 88) (background light)) (:foreground "Black")))) '(minibuffer-prompt ((t (:foreground "medium blue")))) '(mode-line ((t (:background "#222222" :foreground "White")))) '(tabbar-button ((t (:inherit tabbar-default :foreground "dark red")))) '(tabbar-button-highlight ((t (:inherit tabbar-default :background "white" :box (:line-width 2 :color "white"))))) '(tabbar-default ((t (:background "gray90" :foreground "gray50" :box (:line-width 3 :color "gray90") :height 100)))) '(tabbar-highlight ((t (:underline t)))) '(tabbar-selected ((t (:inherit tabbar-default :foreground "blue" :weight bold)))) '(tabbar-separator ((t nil))) '(tabbar-unselected ((t (:inherit tabbar-default))))) Any suggestions? Kind regards, mefiX

  Read the article

• Use a single freemarker template to display tables of arbitrary pojos

  - by Kevin Pauli

  Attention advanced Freemarker gurus: I want to use a single freemarker template to be able to output tables of arbitrary pojos, with the columns to display defined separately than the data. The problem is that I can't figure out how to get a handle to a function on a pojo at runtime, and then have freemarker invoke that function (lambda style). From skimming the docs it seems that Freemarker supports functional programming, but I can't seem to forumulate the proper incantation. I whipped up a simplistic concrete example. Let's say I have two lists: a list of people with a firstName and lastName, and a list of cars with a make and model. would like to output these two tables: <table> <tr> <th>firstName</th> <th>lastName</th> </tr> <tr> <td>Joe</td> <td>Blow</d> </tr> <tr> <td>Mary</td> <td>Jane</d> </tr> </table> and <table> <tr> <th>make</th> <th>model</th> </tr> <tr> <td>Toyota</td> <td>Tundra</d> </tr> <tr> <td>Honda</td> <td>Odyssey</d> </tr> </table> But I want to use the same template, since this is part of a framework that has to deal with dozens of different pojo types. Given the following code: public class FreemarkerTest { public static class Table { private final List<Column> columns = new ArrayList<Column>(); public Table(Column[] columns) { this.columns.addAll(Arrays.asList(columns)); } public List<Column> getColumns() { return columns; } } public static class Column { private final String name; public Column(String name) { this.name = name; } public String getName() { return name; } } public static class Person { private final String firstName; private final String lastName; public Person(String firstName, String lastName) { this.firstName = firstName; this.lastName = lastName; } public String getFirstName() { return firstName; } public String getLastName() { return lastName; } } public static class Car { String make; String model; public Car(String make, String model) { this.make = make; this.model = model; } public String getMake() { return make; } public String getModel() { return model; } } public static void main(String[] args) throws Exception { final Table personTableDefinition = new Table(new Column[] { new Column("firstName"), new Column("lastName") }); final List<Person> people = Arrays.asList(new Person[] { new Person("Joe", "Blow"), new Person("Mary", "Jane") }); final Table carTable = new Table(new Column[] { new Column("make"), new Column("model") }); final List<Car> cars = Arrays.asList(new Car[] { new Car("Toyota", "Tundra"), new Car("Honda", "Odyssey") }); final Configuration cfg = new Configuration(); cfg.setClassForTemplateLoading(FreemarkerTest.class, ""); cfg.setObjectWrapper(new DefaultObjectWrapper()); final Template template = cfg.getTemplate("test.ftl"); process(template, personTableDefinition, people); process(template, carTable, cars); } private static void process(Template template, Table tableDefinition, List<? extends Object> data) throws Exception { final Map<String, Object> dataMap = new HashMap<String, Object>(); dataMap.put("tableDefinition", tableDefinition); dataMap.put("data", data); final Writer out = new OutputStreamWriter(System.out); template.process(dataMap, out); out.flush(); } } All the above is a given for this problem. So here is the template I have been hacking on. Note the comment where I am having trouble. <table> <tr> <#list tableDefinition.columns as col> <th>${col.name}</th> </#list> </tr> <#list data as pojo> <tr> <#list tableDefinition.columns as col> <td><#-- what goes here? --></td> </#list> </tr> </#list> </table> So col.name has the name of the property I want to access from the pojo. I have tried a few things, such as pojo.col.name and <#assign property = col.name/> ${pojo.property} but of course these don't work, I just included them to help convey my intent. I am looking for a way to get a handle to a function and have freemarker invoke it, or perhaps some kind of "evaluate" feature that can take an arbitrary expression as a string and evaluate it at runtime.

  Read the article

• Parsing HTML using HTTP Agility Pack

  - by Pajci

  Here is one table out of 5: <h3>marec - maj 2009</h3> <div class="graf_table"> <table summary="layout table"> <tr> <th>DATUM</th> <td class="datum">10.03.2009</td> <td class="datum">24.03.2009</td> <td class="datum">07.04.2009</td> <td class="datum">21.04.2009</td> <td class="datum">05.05.2009</td> <td class="datum">06.05.2009</td> </tr> <tr> <th>Maloprodajna cena [EUR/L]</th> <td>0,96000</td> <td>0,97000</td> <td>0,99600</td> <td>1,00800</td> <td>1,00800</td> <td>1,01000</td> </tr> <tr> <th>Maloprodajna cena [SIT/L]</th> <td>230,054</td> <td>232,451</td> <td>238,681</td> <td>241,557</td> <td>241,557</td> <td>242,036</td> </tr> <tr> <th>Prodajna cena brez dajatev</th> <td>0,33795</td> <td>0,34628</td> <td>0,36795</td> <td>0,37795</td> <td>0,37795</td> <td>0,37962</td> </tr> <tr> <th>Trošarina</th> <td>0,46205</td> <td>0,46205</td> <td>0,46205</td> <td>0,46205</td> <td>0,46205</td> <td>0,46205</td> </tr> <tr> <th>DDV</th> <td>0,16000</td> <td>0,16167</td> <td>0,16600</td> <td>0,16800</td> <td>0,16800</td> <td>0,16833</td> </tr> </table> </div> I have to extract out values, where table header is DATUM and Maloprodajna cena [EUR/L]. I am using Agility HTML pack. this.htmlDoc = new HtmlAgilityPack.HtmlDocument(); this.htmlDoc.OptionCheckSyntax = true; this.htmlDoc.OptionFixNestedTags = true; this.htmlDoc.OptionAutoCloseOnEnd = true; this.htmlDoc.OptionOutputAsXml = true; // is this necessary ?? this.htmlDoc.OptionDefaultStreamEncoding = System.Text.Encoding.Default; I had a lot of trouble with getting those values out. I started with: var query = from html in doc.DocumentNode.SelectNodes("//div[@class='graf_table']").Cast<HtmlNode>() from table in html.SelectNodes("//table").Cast<HtmlNode>() from row in table.SelectNodes("tr").Cast<HtmlNode>() from cell in row.SelectNodes("th|td").Cast<HtmlNode>() select new { Table = table.Id, CellText = cell.InnerHtml }; but could not figure out a way to select only values where table header is DATUM and Maloprodajna cena[EUR/L]. Is it possible to do that with where clause? Then I ended with those two queries: var date = (from d in htmlDoc.DocumentNode.SelectNodes("//div[@class='graf_table']//table//tr[1]/td") select DateTime.Parse(d.InnerText)).ToArray(); var price = (from p in htmlDoc.DocumentNode.SelectNodes("//div[@class='graf_table']//table//tr[2]/td") select double.Parse(p.InnerText)).ToArray(); Is it possible to combine those two queries? And how would I convert that to lambda expression? I just started to learn those things and I would like to know how it is done so that in the future I would not have those question. O, one more question ... does anybody know any graph control, cause I have to show those values in graph. I started with Microsoft Chart Controls, but I am having trouble with setting it. So if anyone has any experience with it I would like to know how to set it, so that x axle will show all values not every second ... example: if I have: 10.03.2009, 24.03.2009, 07.04.2009, 21.04.2009, 05.05.2009, 06.05.2009 it show only: 10.03.2009, 07.04.2009, 05.05.2009, ect. I bind data to graph like that: chart1.Series["Series1"].Points.DataBindXY(date, price); I lot of questions for my fist post ... hehe, hope that I was not indistinct or something. Thank's for any reply!

  Read the article

• Why is this RMagick call generating a segmentation fault?

  - by Grant Heaslip

  I've been banging my head against the wall for the better part of an hour trying to figure out what's going wrong here, and I'm sure (or rather hoping) it's something fairly obvious that I'm overlooking. I'm using Ruby 1.9.1, Sinatra 1.0, and RMagick 2.13.1. ImageMagick and RMagick are correctly installed and functional—I've successfully manipulated and saved images from irb. The relevant part of the params array (formatting changes for the sake of readability): {"admin_user_new_image_file"=> { :filename=>"freddie-on-shetland-pony.png", :type=>"image/png", :name=>"admin_user_new_image_file", :tempfile=>#<File:/var/folders/a7/a7pO5jMcGLCww9XBGRvWfE+++TI/-Tmp-/RackMultipart20100514-20700-o2tkqu-0>, :head=>"Content-Disposition: form-data; name=\"admin_user_new_image_file\"; filename=\"freddie-on-shetland-pony.png\"\r\nContent-Type: image/png\r\n" } } The relevant code: post "/admin/user/:account_name/image/new/" do if params[:admin_user_new_image_file][:tempfile] thumbnail = Magick::Image.read("png:"+params[:admin_user_new_image_file][:tempfile].path).first end end The error (line 229 is the line starting with "thumbnail = ": config.ru:229: [BUG] Segmentation fault ruby 1.9.1p376 (2009-12-07 revision 26041) [i386-darwin10.3.0] -- control frame ---------- c:0042 p:---- s:0196 b:0196 l:000195 d:000195 CFUNC :read c:0041 p:0121 s:0192 b:0192 l:001ab8 d:000191 LAMBDA config.ru:229 c:0040 p:---- s:0189 b:0189 l:000188 d:000188 FINISH c:0039 p:---- s:0187 b:0187 l:000186 d:000186 CFUNC :call c:0038 p:0018 s:0184 b:0184 l:001d78 d:000183 BLOCK /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:865 c:0037 p:---- s:0182 b:0182 l:000181 d:000181 FINISH c:0036 p:---- s:0180 b:0180 l:000179 d:000179 CFUNC :instance_eval c:0035 p:0016 s:0177 b:0175 l:000174 d:000174 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:521 c:0034 p:0024 s:0171 b:0171 l:000148 d:000170 BLOCK /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:500 c:0033 p:---- s:0169 b:0169 l:000168 d:000168 FINISH c:0032 p:---- s:0167 b:0167 l:000166 d:000166 CFUNC :catch c:0031 p:0140 s:0163 b:0163 l:000148 d:000162 BLOCK /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:497 c:0030 p:---- s:0154 b:0154 l:000153 d:000153 FINISH c:0029 p:---- s:0152 b:0152 l:000151 d:000151 CFUNC :each c:0028 p:0073 s:0149 b:0149 l:000148 d:000148 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:476 c:0027 p:0076 s:0141 b:0141 l:000140 d:000140 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:601 c:0026 p:0009 s:0137 b:0137 l:000138 d:000136 BLOCK /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:411 c:0025 p:---- s:0135 b:0135 l:000134 d:000134 FINISH c:0024 p:---- s:0133 b:0133 l:000132 d:000132 CFUNC :instance_eval c:0023 p:0012 s:0130 b:0130 l:000121 d:000129 BLOCK /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:566 c:0022 p:---- s:0128 b:0128 l:000127 d:000127 FINISH c:0021 p:---- s:0126 b:0126 l:000125 d:000125 CFUNC :catch c:0020 p:0013 s:0122 b:0122 l:000121 d:000121 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:566 c:0019 p:0098 s:0115 b:0115 l:000138 d:000138 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:411 c:0018 p:0019 s:0108 b:0108 l:000107 d:000107 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:399 c:0017 p:0014 s:0104 b:0104 l:000103 d:000103 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/showexceptions.rb:24 c:0016 p:0150 s:0098 b:0098 l:000097 d:000097 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/methodoverride.rb:24 c:0015 p:0031 s:0092 b:0092 l:000091 d:000091 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/commonlogger.rb:18 c:0014 p:0018 s:0084 b:0084 l:002080 d:000083 BLOCK /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:979 c:0013 p:0032 s:0082 b:0082 l:000081 d:000081 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:1005 c:0012 p:0011 s:0078 b:0078 l:002080 d:002080 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:979 c:0011 p:0100 s:0074 b:0074 l:000ff0 d:000ff0 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/lint.rb:47 c:0010 p:0022 s:0068 b:0068 l:000067 d:000067 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/lint.rb:35 c:0009 p:0014 s:0064 b:0064 l:000063 d:000063 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/showexceptions.rb:24 c:0008 p:0031 s:0058 b:0058 l:000057 d:000057 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/commonlogger.rb:18 c:0007 p:0014 s:0050 b:0050 l:000049 d:000049 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/content_length.rb:13 c:0006 p:0320 s:0042 b:0042 l:000041 d:000041 METHOD /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/handler/webrick.rb:48 c:0005 p:0256 s:0030 b:0030 l:000029 d:000029 METHOD /usr/local/lib/ruby/1.9.1/webrick/httpserver.rb:111 c:0004 p:0382 s:0020 b:0020 l:000019 d:000019 METHOD /usr/local/lib/ruby/1.9.1/webrick/httpserver.rb:70 c:0003 p:0123 s:0009 b:0009 l:000bc8 d:000008 BLOCK /usr/local/lib/ruby/1.9.1/webrick/server.rb:183 c:0002 p:---- s:0004 b:0004 l:000003 d:000003 FINISH c:0001 p:---- s:0002 b:0002 l:000001 d:000001 TOP --------------------------- -- Ruby level backtrace information----------------------------------------- config.ru:229:in `read' config.ru:229:in `block (2 levels) in <main>' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:865:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:865:in `block in route' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:521:in `instance_eval' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:521:in `route_eval' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:500:in `block (2 levels) in route!' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:497:in `catch' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:497:in `block in route!' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:476:in `each' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:476:in `route!' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:601:in `dispatch!' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:411:in `block in call!' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `instance_eval' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `block in invoke' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `catch' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:566:in `invoke' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:411:in `call!' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:399:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/showexceptions.rb:24:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/methodoverride.rb:24:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/commonlogger.rb:18:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:979:in `block in call' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:1005:in `synchronize' /usr/local/lib/ruby/gems/1.9.1/gems/sinatra-1.0/lib/sinatra/base.rb:979:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/lint.rb:47:in `_call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/lint.rb:35:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/showexceptions.rb:24:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/commonlogger.rb:18:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/content_length.rb:13:in `call' /usr/local/lib/ruby/gems/1.9.1/gems/rack-1.1.0/lib/rack/handler/webrick.rb:48:in `service' /usr/local/lib/ruby/1.9.1/webrick/httpserver.rb:111:in `service' /usr/local/lib/ruby/1.9.1/webrick/httpserver.rb:70:in `run' /usr/local/lib/ruby/1.9.1/webrick/server.rb:183:in `block in start_thread' -- C level backtrace information ------------------------------------------- 0x10010cd8d 0 libruby.dylib 0x000000010010cd8d rb_vm_bugreport + 77 0x10002b184 1 libruby.dylib 0x000000010002b184 report_bug + 260 0x10002b318 2 libruby.dylib 0x000000010002b318 rb_bug + 200 0x1000b7124 3 libruby.dylib 0x00000001000b7124 sigsegv + 132 0x7fff8301c80a 4 libSystem.B.dylib 0x00007fff8301c80a _sigtramp + 26 0x1032313ac 5 libMagickCore.3.dylib 0x00000001032313ac Splay + 300 0x103119245 6 libMagickCore.3.dylib 0x0000000103119245 AcquirePixelCache + 325 0x1031cb317 7 libMagickCore.3.dylib 0x00000001031cb317 AcquireImage + 375 0x10333035b 8 libMagickCore.3.dylib 0x000000010333035b ReadPNGImage + 155 0x1031418fd 9 libMagickCore.3.dylib 0x00000001031418fd ReadImage + 2221 0x101f1b72b 10 RMagick2.bundle 0x0000000101f1b72b rd_image + 339 0x101f1b59b 11 RMagick2.bundle 0x0000000101f1b59b Image_read + 36 0x1000fd0e4 12 libruby.dylib 0x00000001000fd0e4 vm_call_cfunc + 340 0x1000fe9b0 13 libruby.dylib 0x00000001000fe9b0 vm_call_method + 896 0x1000ff8fc 14 libruby.dylib 0x00000001000ff8fc vm_exec_core + 3180 0x100104b93 15 libruby.dylib 0x0000000100104b93 vm_exec + 1203 0x100106643 16 libruby.dylib 0x0000000100106643 rb_vm_invoke_proc + 691 0x100106ccd 17 libruby.dylib 0x0000000100106ccd vm_call0 + 1085 0x1000317c6 18 libruby.dylib 0x00000001000317c6 rb_method_call + 406 0x1000fd0e4 19 libruby.dylib 0x00000001000fd0e4 vm_call_cfunc + 340 0x1000fe9b0 20 libruby.dylib 0x00000001000fe9b0 vm_call_method + 896 0x1000ff8fc 21 libruby.dylib 0x00000001000ff8fc vm_exec_core + 3180 0x100104b93 22 libruby.dylib 0x0000000100104b93 vm_exec + 1203 0x100105ce6 23 libruby.dylib 0x0000000100105ce6 yield_under + 710 0x100106188 24 libruby.dylib 0x0000000100106188 specific_eval + 72 0x1000fd0e4 25 libruby.dylib 0x00000001000fd0e4 vm_call_cfunc + 340 0x1000fe9b0 26 libruby.dylib 0x00000001000fe9b0 vm_call_method + 896 0x1000ff8fc 27 libruby.dylib 0x00000001000ff8fc vm_exec_core + 3180 0x100104b93 28 libruby.dylib 0x0000000100104b93 vm_exec + 1203 0x10010b6bf 29 libruby.dylib 0x000000010010b6bf rb_f_catch + 639 0x1000fd0e4 30 libruby.dylib 0x00000001000fd0e4 vm_call_cfunc + 340 0x1000fe9b0 31 libruby.dylib 0x00000001000fe9b0 vm_call_method + 896 0x1000ff8fc 32 libruby.dylib 0x00000001000ff8fc vm_exec_core + 3180 0x100104b93 33 libruby.dylib 0x0000000100104b93 vm_exec + 1203 0x10010aac9 34 libruby.dylib 0x000000010010aac9 rb_yield + 505 0x100007902 35 libruby.dylib 0x0000000100007902 rb_ary_each + 82 0x1000fd0e4 36 libruby.dylib 0x00000001000fd0e4 vm_call_cfunc + 340 0x1000fe9b0 37 libruby.dylib 0x00000001000fe9b0 vm_call_method + 896 0x1000ff8fc 38 libruby.dylib 0x00000001000ff8fc vm_exec_core + 3180 0x100104b93 39 libruby.dylib 0x0000000100104b93 vm_exec + 1203 0x100105ce6 40 libruby.dylib 0x0000000100105ce6 yield_under + 710 0x100106188 41 libruby.dylib 0x0000000100106188 specific_eval + 72 0x1000fd0e4 42 libruby.dylib 0x00000001000fd0e4 vm_call_cfunc + 340 0x1000fe9b0 43 libruby.dylib 0x00000001000fe9b0 vm_call_method + 896 0x1000ff8fc 44 libruby.dylib 0x00000001000ff8fc vm_exec_core + 3180 0x100104b93 45 libruby.dylib 0x0000000100104b93 vm_exec + 1203 0x10010b6bf 46 libruby.dylib 0x000000010010b6bf rb_f_catch + 639 0x1000fd0e4 47 libruby.dylib 0x00000001000fd0e4 vm_call_cfunc + 340 0x1000fe9b0 48 libruby.dylib 0x00000001000fe9b0 vm_call_method + 896 0x1000ff8fc 49 libruby.dylib 0x00000001000ff8fc vm_exec_core + 3180 0x100104b93 50 libruby.dylib 0x0000000100104b93 vm_exec + 1203 0x100106643 51 libruby.dylib 0x0000000100106643 rb_vm_invoke_proc + 691 0x100111803 52 libruby.dylib 0x0000000100111803 thread_start_func_2 + 835 0x100111921 53 libruby.dylib 0x0000000100111921 thread_start_func_1 + 17 0x7fff82ff58b6 54 libSystem.B.dylib 0x00007fff82ff58b6 _pthread_start + 331 0x7fff82ff5769 55 libSystem.B.dylib 0x00007fff82ff5769 thread_start + 13 [NOTE] You may encounter a bug of Ruby interpreter. Bug reports are welcome. For details: http://www.ruby-lang.org/bugreport.html Abort trap Anyone have any idea what's going on? Thanks!

  Read the article

• pyqt QObject: Cannot create children for a parent that is in a different thread

  - by memomk

  QObject: Cannot create children for a parent that is in a different thread. (Parent is QTextDocument(0x9919018), parent's thread is QThread(0x97331e0), current thread is flooderthread(0x97b4c10) error means ? am sorry because am new to pyqt here is the code : i know the code is finished yet but it should work i guess the problem is with myfun.log function... #! /usr/bin/python # -*- coding: utf-8 -*- import urllib, urllib2, itertools, threading, cookielib, Cookie, sys, time, hashlib, os from PyQt4 import QtCore, QtGui try: _fromUtf8 = QtCore.QString.fromUtf8 except AttributeError: _fromUtf8 = lambda s: s gui=QtGui.QApplication.processEvents texttoset="" class fun(): global texttoset def checkpassword(self): if ui.passwordcheck.isChecked()==True: return 1 else : return 0 def log(self, text): if text != False: firsttext=str(ui.console.toPlainText()) secondtext=firsttext+text+"\n" ui.console.setText(secondtext) log=open("log.log", "a") log.write(text+"\n") log.close() else : firsttext=str(ui.console.toPlainText()) secondtext=firsttext+texttoset+"\n" ui.console.setText(secondtext) log=open("log.log", "a") log.write(texttoset+"\n") log.close() def disable(self): MainWindow.setEnabled(False) pass def enable(self): MainWindow.setEnabled(True) pass def checkmethod(self): if ui.get.isChecked()==True: return 1 elif ui.post.isChecked()==True: return 2 else : return 0 def main(self): connecter() gui() f1.start() gui() time.sleep(3) gui() f2.start() gui() time.sleep(3) gui() f3.start() gui() time.sleep(3) gui() f4.start() gui() time.sleep(3) gui() f5.start() gui() self.sleep(3) gui() f6.start() gui() def killer(self): f1.terminate() f2.terminate() f3.terminate() f4.terminate() f5.terminate() f6.terminate() def close(self): self.killer() os.abort() sys.exit() myfun=fun() def connecter(): QtCore.QObject.connect(f1, QtCore.SIGNAL("log(bool)"), myfun.log) QtCore.QObject.connect(f1, QtCore.SIGNAL("enable()"), myfun.enable) QtCore.QObject.connect(f1, QtCore.SIGNAL("disable()"), myfun.disable) QtCore.QObject.connect(f2, QtCore.SIGNAL("log(bool)"), myfun.log) QtCore.QObject.connect(f2, QtCore.SIGNAL("enable()"), myfun.enable) QtCore.QObject.connect(f2, QtCore.SIGNAL("disable()"), myfun.disable) QtCore.QObject.connect(f3, QtCore.SIGNAL("log(bool)"), myfun.log) QtCore.QObject.connect(f3, QtCore.SIGNAL("enable()"), myfun.enable) QtCore.QObject.connect(f3, QtCore.SIGNAL("disable()"), myfun.disable) QtCore.QObject.connect(f4, QtCore.SIGNAL("log(bool)"), myfun.log) QtCore.QObject.connect(f4, QtCore.SIGNAL("enable()"), myfun.enable) QtCore.QObject.connect(f4, QtCore.SIGNAL("disable()"), myfun.disable) QtCore.QObject.connect(f5, QtCore.SIGNAL("log(bool)"), myfun.log) QtCore.QObject.connect(f5, QtCore.SIGNAL("enable()"), myfun.enable) QtCore.QObject.connect(f5, QtCore.SIGNAL("disable()"), myfun.disable) QtCore.QObject.connect(f6, QtCore.SIGNAL("log(bool)"), myfun.log) QtCore.QObject.connect(f6, QtCore.SIGNAL("enable()"), myfun.enable) QtCore.QObject.connect(f6, QtCore.SIGNAL("disable()"), myfun.disable) x=0 num=0 class flooderthread(QtCore.QThread): global texttoset def __init__(self, x, num): QtCore.QThread.__init__(self) self.x=x self.num=num def log(self, text): texttolog=str(text) time.sleep(1) self.emit(QtCore.SIGNAL("log(bool)"), False) time.sleep(2) def enable(self): time.sleep(1) self.emit(QtCore.SIGNAL("enable()")) def disable(self): time.sleep(1) self.emit(QtCore.SIGNAL("disable()")) def run(self): connecter() self.log("\n\n--------------------------------------------------new session-------------------------------------\n\n") itered=False gui() self.disable() gui() self.log("setting params...") param={ui.dataname1.text():ui.datavalue1.text(),ui.dataname3.text():ui.datavalue3.text(),ui.dataname3.text():ui.datavalue3.text(), } self.log("checking password...") if myfun.checkpassword()==1: itered=True self.log("password is true") else : self.log("password is null ") self.log("itered operation") self.log("setting url") url=str(ui.url.text()) if url[:4]!="http" and url[:3]!="ftp": self.log("url error exiting the whole function") self.log("please set a valide protocole!!") gui() self.enable() gui() return 1 pass else : self.log("valid url") gui() self.log("url is "+url) self.log("setting proxy") proxy="http://"+ui.proxyuser.text()+":"+ui.proxypass.text()+"@"+ui.proxyhost.text()+":"+ui.proxyport.text() self.log("proxy is "+proxy) gui() self.log("preparing params...") urlparam=urllib.urlencode(param) gui() self.log("params are "+urlparam) self.log("setting up headers...") header={'User-Agent':str(ui.useragent.toPlainText())} self.log("headers are "+ str(header)) self.log("setting up proxy handler..") proxyhandler=urllib2.ProxyHandler({"http":str(proxy)}) self.log("checking method") if myfun.checkmethod()==1: self.log("method is get..") self.log("setting request..") finalurl=url+urlparam gui() self.log("final url is"+finalurl) req=urllib2.Request(finalurl, None, headers) elif myfun.checkmethod()==2: self.log("method is post...") self.log("setting request..") finalurl=url gui() self.log("final url is "+finalurl) req=urllib2.Request(finalurl, urlparam, header) else : self.log("error has been accourded") self.log("please select a method!!") gui() self.log("exiting the whole functions") gui() self.enable() return 1 pass self.log("intilizing cookies..") c1=Cookie.SimpleCookie() c1[str(ui.cookiename1.text())]=str(ui.cookievalue1.text()) c1[str(ui.cookiename1.text())]['path']='/' c1[str(ui.cookiename2.text())]=str(ui.cookievalue2.text()) c1[str(ui.cookiename2.text())]['path']='/' c1[str(ui.cookiename3.text())]=str(ui.cookievalue3.text()) c1[str(ui.cookiename3.text())]['domain']=url c1[str(ui.cookiename3.text())]['path']='/' c1[str(ui.cookiename4.text())]=str(ui.cookievalue4.text()) c1[str(ui.cookiename4.text())]['domain']=url c1[str(ui.cookiename4.text())]['path']='/' self.log("cookies are.. :"+str(c1)) cj=cookielib.CookieJar() cj.set_cookie(c1) opener = urllib2.build_opener(proxyhandler, urllib2.HTTPCookieProcessor(cj)) self.log("insatlling opener") urllib2.install_opener(opener) self.log("setting the two operations....") if itered==Fasle: self.log("starting the flooding loop") gui() while true: try: gui() opener.open(req) except e: self.log("error connecting : "+e.reason) self.log("will continue....") continue gui() elif itered==True: pass f1=flooderthread(1, 1) f2=flooderthread(2, 2) f3=flooderthread(3, 3) f4=flooderthread(4, 4) f5=flooderthread(5, 5) f6=flooderthread(6, 6) class Ui_MainWindow(object): def setupUi(self, MainWindow): MainWindow.setObjectName(_fromUtf8("MainWindow")) MainWindow.setMinimumSize(QtCore.QSize(838, 500)) MainWindow.setMaximumSize(QtCore.QSize(838, 500)) MainWindow.setWindowTitle(QtGui.QApplication.translate("MainWindow", "memo flooder", None, QtGui.QApplication.UnicodeUTF8)) self.centralwidget = QtGui.QWidget(MainWindow) self.centralwidget.setObjectName(_fromUtf8("centralwidget")) self.console=QtGui.QTextEdit(self.centralwidget) self.console.setGeometry(10, 350, 800,130) self.console.setReadOnly(True) self.console.setObjectName("console") self.groupBox = QtGui.QGroupBox(self.centralwidget) self.groupBox.setGeometry(QtCore.QRect(30, 50, 71, 80)) self.groupBox.setTitle(QtGui.QApplication.translate("MainWindow", "method:", None, QtGui.QApplication.UnicodeUTF8)) self.groupBox.setObjectName(_fromUtf8("groupBox")) self.post = QtGui.QRadioButton(self.groupBox) self.post.setGeometry(QtCore.QRect(10, 20, 61, 22)) self.post.setText(QtGui.QApplication.translate("MainWindow", "post", None, QtGui.QApplication.UnicodeUTF8)) self.post.setChecked(True) self.post.setObjectName(_fromUtf8("post")) self.get = QtGui.QRadioButton(self.groupBox) self.get.setGeometry(QtCore.QRect(10, 50, 51, 22)) self.get.setText(QtGui.QApplication.translate("MainWindow", "get", None, QtGui.QApplication.UnicodeUTF8)) self.get.setObjectName(_fromUtf8("get")) self.url = QtGui.QLineEdit(self.centralwidget) self.url.setGeometry(QtCore.QRect(70, 20, 671, 27)) self.url.setInputMethodHints(QtCore.Qt.ImhUrlCharactersOnly) self.url.setObjectName(_fromUtf8("url")) self.groupBox_2 = QtGui.QGroupBox(self.centralwidget) self.groupBox_2.setGeometry(QtCore.QRect(110, 50, 371, 111)) self.groupBox_2.setTitle(QtGui.QApplication.translate("MainWindow", "data:", None, QtGui.QApplication.UnicodeUTF8)) self.groupBox_2.setObjectName(_fromUtf8("groupBox_2")) self.dataname1 = QtGui.QLineEdit(self.groupBox_2) self.dataname1.setGeometry(QtCore.QRect(20, 30, 101, 27)) self.dataname1.setObjectName(_fromUtf8("dataname1")) self.label = QtGui.QLabel(self.groupBox_2) self.label.setGeometry(QtCore.QRect(40, 10, 67, 17)) self.label.setText(QtGui.QApplication.translate("MainWindow", "name:", None, QtGui.QApplication.UnicodeUTF8)) self.label.setObjectName(_fromUtf8("label")) self.dataname2 = QtGui.QLineEdit(self.groupBox_2) self.dataname2.setGeometry(QtCore.QRect(130, 30, 113, 27)) self.dataname2.setObjectName(_fromUtf8("dataname2")) self.dataname3 = QtGui.QLineEdit(self.groupBox_2) self.dataname3.setGeometry(QtCore.QRect(250, 30, 113, 27)) self.dataname3.setObjectName(_fromUtf8("dataname3")) self.label_2 = QtGui.QLabel(self.groupBox_2) self.label_2.setGeometry(QtCore.QRect(40, 60, 67, 17)) self.label_2.setText(QtGui.QApplication.translate("MainWindow", "value:", None, QtGui.QApplication.UnicodeUTF8)) self.label_2.setObjectName(_fromUtf8("label_2")) self.datavalue1 = QtGui.QLineEdit(self.groupBox_2) self.datavalue1.setGeometry(QtCore.QRect(20, 80, 101, 27)) self.datavalue1.setObjectName(_fromUtf8("datavalue1")) self.datavalue2 = QtGui.QLineEdit(self.groupBox_2) self.datavalue2.setGeometry(QtCore.QRect(130, 80, 113, 27)) self.datavalue2.setObjectName(_fromUtf8("datavalue2")) self.datavalue3 = QtGui.QLineEdit(self.groupBox_2) self.datavalue3.setGeometry(QtCore.QRect(250, 80, 113, 27)) self.datavalue3.setObjectName(_fromUtf8("datavalue3")) self.groupBox_4 = QtGui.QGroupBox(self.centralwidget) self.groupBox_4.setGeometry(QtCore.QRect(670, 50, 151, 111)) self.groupBox_4.setTitle(QtGui.QApplication.translate("MainWindow", "password:", None, QtGui.QApplication.UnicodeUTF8)) self.groupBox_4.setObjectName(_fromUtf8("groupBox_4")) self.passname = QtGui.QLineEdit(self.groupBox_4) self.passname.setGeometry(QtCore.QRect(10, 30, 113, 27)) self.passname.setObjectName(_fromUtf8("passname")) self.passvalue = QtGui.QLineEdit(self.groupBox_4) self.passvalue.setGeometry(QtCore.QRect(10, 80, 113, 27)) self.passvalue.setObjectName(_fromUtf8("passvalue")) self.passwordcheck = QtGui.QCheckBox(self.centralwidget) self.passwordcheck.setGeometry(QtCore.QRect(670, 180, 97, 22)) self.passwordcheck.setText(QtGui.QApplication.translate("MainWindow", "password", None, QtGui.QApplication.UnicodeUTF8)) self.passwordcheck.setChecked(True) self.passwordcheck.setObjectName(_fromUtf8("passwordcheck")) self.groupBox_5 = QtGui.QGroupBox(self.centralwidget) self.groupBox_5.setGeometry(QtCore.QRect(29, 169, 441, 81)) self.groupBox_5.setTitle(QtGui.QApplication.translate("MainWindow", "proxy:", None, QtGui.QApplication.UnicodeUTF8)) self.groupBox_5.setObjectName(_fromUtf8("groupBox_5")) self.proxyhost = QtGui.QLineEdit(self.groupBox_5) self.proxyhost.setGeometry(QtCore.QRect(20, 30, 113, 27)) self.proxyhost.setObjectName(_fromUtf8("proxyhost")) self.proxyport = QtGui.QLineEdit(self.groupBox_5) self.proxyport.setGeometry(QtCore.QRect(140, 30, 51, 27)) self.proxyport.setInputMethodHints(QtCore.Qt.ImhDigitsOnly|QtCore.Qt.ImhPreferNumbers) self.proxyport.setObjectName(_fromUtf8("proxyport")) self.proxyuser = QtGui.QLineEdit(self.groupBox_5) self.proxyuser.setGeometry(QtCore.QRect(200, 30, 113, 27)) self.proxyuser.setObjectName(_fromUtf8("proxyuser")) self.proxypass = QtGui.QLineEdit(self.groupBox_5) self.proxypass.setGeometry(QtCore.QRect(320, 30, 113, 27)) self.proxypass.setObjectName(_fromUtf8("proxypass")) self.label_4 = QtGui.QLabel(self.groupBox_5) self.label_4.setGeometry(QtCore.QRect(100, 10, 67, 17)) self.label_4.setText(QtGui.QApplication.translate("MainWindow", "host", None, QtGui.QApplication.UnicodeUTF8)) self.label_4.setObjectName(_fromUtf8("label_4")) self.label_5 = QtGui.QLabel(self.groupBox_5) self.label_5.setGeometry(QtCore.QRect(150, 10, 67, 17)) self.label_5.setText(QtGui.QApplication.translate("MainWindow", "port", None, QtGui.QApplication.UnicodeUTF8)) self.label_5.setObjectName(_fromUtf8("label_5")) self.label_6 = QtGui.QLabel(self.groupBox_5) self.label_6.setGeometry(QtCore.QRect(200, 10, 67, 17)) self.label_6.setText(QtGui.QApplication.translate("MainWindow", "username", None, QtGui.QApplication.UnicodeUTF8)) self.label_6.setObjectName(_fromUtf8("label_6")) self.label_7 = QtGui.QLabel(self.groupBox_5) self.label_7.setGeometry(QtCore.QRect(320, 10, 67, 17)) self.label_7.setText(QtGui.QApplication.translate("MainWindow", "password", None, QtGui.QApplication.UnicodeUTF8)) self.label_7.setObjectName(_fromUtf8("label_7")) self.groupBox_6 = QtGui.QGroupBox(self.centralwidget) self.groupBox_6.setGeometry(QtCore.QRect(30, 260, 531, 91)) self.groupBox_6.setTitle(QtGui.QApplication.translate("MainWindow", "cookies:", None, QtGui.QApplication.UnicodeUTF8)) self.groupBox_6.setObjectName(_fromUtf8("groupBox_6")) self.cookiename1 = QtGui.QLineEdit(self.groupBox_6) self.cookiename1.setGeometry(QtCore.QRect(10, 20, 113, 27)) self.cookiename1.setObjectName(_fromUtf8("cookiename1")) self.cookiename2 = QtGui.QLineEdit(self.groupBox_6) self.cookiename2.setGeometry(QtCore.QRect(140, 20, 113, 27)) self.cookiename2.setObjectName(_fromUtf8("cookename2")) self.cookiename3 = QtGui.QLineEdit(self.groupBox_6) self.cookiename3.setGeometry(QtCore.QRect(270, 20, 113, 27)) self.cookiename3.setObjectName(_fromUtf8("cookiename3")) self.cookiename4 = QtGui.QLineEdit(self.groupBox_6) self.cookiename4.setGeometry(QtCore.QRect(390, 20, 113, 27)) self.cookiename4.setObjectName(_fromUtf8("cookiename4")) self.cookievalue1 = QtGui.QLineEdit(self.groupBox_6) self.cookievalue1.setGeometry(QtCore.QRect(10, 50, 113, 27)) self.cookievalue1.setObjectName(_fromUtf8("cookievalue1")) self.cookievalue2 = QtGui.QLineEdit(self.groupBox_6) self.cookievalue2.setGeometry(QtCore.QRect(140, 50, 113, 27)) self.cookievalue2.setObjectName(_fromUtf8("cookievalue2")) self.cookievalue3 = QtGui.QLineEdit(self.groupBox_6) self.cookievalue3.setGeometry(QtCore.QRect(270, 50, 113, 27)) self.cookievalue3.setObjectName(_fromUtf8("cookievalue3")) self.cookievalue4 = QtGui.QLineEdit(self.groupBox_6) self.cookievalue4.setGeometry(QtCore.QRect(390, 50, 113, 27)) self.cookievalue4.setObjectName(_fromUtf8("cookievalue4")) self.groupBox_7 = QtGui.QGroupBox(self.centralwidget) self.groupBox_7.setGeometry(QtCore.QRect(570, 260, 251, 80)) self.groupBox_7.setTitle(QtGui.QApplication.translate("MainWindow", "useragents:", None, QtGui.QApplication.UnicodeUTF8)) self.groupBox_7.setObjectName(_fromUtf8("groupBox_7")) self.useragent = QtGui.QTextEdit(self.groupBox_7) self.useragent.setGeometry(QtCore.QRect(10, 20, 211, 51)) self.useragent.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn) self.useragent.setObjectName(_fromUtf8("useragent")) self.start = QtGui.QPushButton(self.centralwidget) self.start.setGeometry(QtCore.QRect(750, 20, 71, 27)) self.start.setText(QtGui.QApplication.translate("MainWindow", "start", None, QtGui.QApplication.UnicodeUTF8)) self.start.setObjectName(_fromUtf8("start")) self.label_3 = QtGui.QLabel(self.centralwidget) self.label_3.setGeometry(QtCore.QRect(30, 20, 67, 17)) self.label_3.setText(QtGui.QApplication.translate("MainWindow", "url :", None, QtGui.QApplication.UnicodeUTF8)) self.label_3.setObjectName(_fromUtf8("label_3")) MainWindow.setCentralWidget(self.centralwidget) QtCore.QObject.connect(self.start, QtCore.SIGNAL(_fromUtf8("clicked(bool)")), myfun.main) QtCore.QObject.connect(self.passwordcheck, QtCore.SIGNAL(_fromUtf8("clicked(bool)")), self.groupBox_4.setEnabled) QtCore.QMetaObject.connectSlotsByName(MainWindow) def __del__(): myfun.killer() os.abort() sys.exit() app = QtGui.QApplication(sys.argv) MainWindow = QtGui.QMainWindow() ui = Ui_MainWindow() ui.setupUi(MainWindow) myfun.log("\n\n--------------------------------------------------new session-------------------------------------\n\n") MainWindow.show() sys.exit(app.exec_())

  Read the article

• PyQt4: Scrollbar doesn't show in scrollarea when resizing dockWidget

  - by Whospal

  I created a python test program (Test_InfoPanel.py) that has MainWindow with dockWidget, and within it, a tabWidget with scrollArea widget. However, when I resize the MainWindow, the vertical scrollbar doesn't auto-appear when the Similarly, when I undock the dockWidget & resize, the vertical scrollbar doesn't auto-appear. Pls help! Test Program (Test_InfoPanel.py): #!/usr/bin/env python # Filename: Test_InfoPanel.py # Date: 2012-Sep-18 ''' This program test the scrollarea to show scrollbars for the InfoPanel_UI. ''' import sys from PyQt4 import QtCore, QtGui if __name__ == "__main__": import sys app = QtGui.QApplication(sys.argv) # Look and feel changed to 'Cleanlooks'. app.setStyle('Cleanlooks') from InfoPanel_UI import Ui_MainWindow_InfoPanel AppWindow = QtGui.QMainWindow() ui = Ui_MainWindow_InfoPanel() ui.setupUi(AppWindow) ui.tabWidget_Info_Panel.setCurrentWidget(ui.scrollArea_Info_Panel) AppWindow.show() sys.exit(app.exec_()) Generated *.ui script (InfoPanel_UI.py): # -*- coding: utf-8 -*- # Form implementation generated from reading ui file 'InfoPanel.ui' # # Created: Wed Sep 19 13:11:06 2012 # by: PyQt4 UI code generator 4.9.4 # # WARNING! All changes made in this file will be lost! from PyQt4 import QtCore, QtGui try: _fromUtf8 = QtCore.QString.fromUtf8 except AttributeError: _fromUtf8 = lambda s: s class Ui_MainWindow_InfoPanel(object): def setupUi(self, MainWindow_InfoPanel): MainWindow_InfoPanel.setObjectName(_fromUtf8("MainWindow_InfoPanel")) MainWindow_InfoPanel.resize(602, 263) MainWindow_InfoPanel.setDocumentMode(False) self.centralwidget = QtGui.QWidget(MainWindow_InfoPanel) self.centralwidget.setObjectName(_fromUtf8("centralwidget")) MainWindow_InfoPanel.setCentralWidget(self.centralwidget) self.statusbar = QtGui.QStatusBar(MainWindow_InfoPanel) self.statusbar.setObjectName(_fromUtf8("statusbar")) MainWindow_InfoPanel.setStatusBar(self.statusbar) self.dockWidget_Info_Panel = QtGui.QDockWidget(MainWindow_InfoPanel) self.dockWidget_Info_Panel.setMinimumSize(QtCore.QSize(300, 140)) font = QtGui.QFont() font.setBold(True) font.setItalic(True) font.setWeight(75) self.dockWidget_Info_Panel.setFont(font) self.dockWidget_Info_Panel.setLayoutDirection(QtCore.Qt.LeftToRight) self.dockWidget_Info_Panel.setAllowedAreas(QtCore.Qt.LeftDockWidgetArea|QtCore.Qt.RightDockWidgetArea) self.dockWidget_Info_Panel.setObjectName(_fromUtf8("dockWidget_Info_Panel")) self.dockWidgetContents_Info_Panel = QtGui.QWidget() self.dockWidgetContents_Info_Panel.setObjectName(_fromUtf8("dockWidgetContents_Info_Panel")) self.tabWidget_Info_Panel = QtGui.QTabWidget(self.dockWidgetContents_Info_Panel) self.tabWidget_Info_Panel.setGeometry(QtCore.QRect(0, 0, 300, 215)) font = QtGui.QFont() font.setBold(False) font.setItalic(False) font.setWeight(50) self.tabWidget_Info_Panel.setFont(font) self.tabWidget_Info_Panel.setObjectName(_fromUtf8("tabWidget_Info_Panel")) self.tab_1 = QtGui.QWidget() self.tab_1.setObjectName(_fromUtf8("tab_1")) self.scrollArea_Info_Panel = QtGui.QScrollArea(self.tab_1) self.scrollArea_Info_Panel.setGeometry(QtCore.QRect(9, 9, 271, 171)) self.scrollArea_Info_Panel.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAsNeeded) self.scrollArea_Info_Panel.setWidgetResizable(True) self.scrollArea_Info_Panel.setObjectName(_fromUtf8("scrollArea_Info_Panel")) self.scrollAreaWidgetContents = QtGui.QWidget() self.scrollAreaWidgetContents.setGeometry(QtCore.QRect(0, 0, 269, 169)) self.scrollAreaWidgetContents.setObjectName(_fromUtf8("scrollAreaWidgetContents")) self.frame_Info_Panel = QtGui.QFrame(self.scrollAreaWidgetContents) self.frame_Info_Panel.setGeometry(QtCore.QRect(0, 0, 261, 161)) self.frame_Info_Panel.setObjectName(_fromUtf8("frame_Info_Panel")) self.label_Eqpt_Model = QtGui.QLabel(self.frame_Info_Panel) self.label_Eqpt_Model.setGeometry(QtCore.QRect(10, 10, 111, 27)) self.label_Eqpt_Model.setObjectName(_fromUtf8("label_Eqpt_Model")) self.lineEdit_Eqpt_Model = QtGui.QLineEdit(self.frame_Info_Panel) self.lineEdit_Eqpt_Model.setEnabled(False) self.lineEdit_Eqpt_Model.setGeometry(QtCore.QRect(120, 10, 111, 27)) palette = QtGui.QPalette() brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Text, brush) self.lineEdit_Eqpt_Model.setPalette(palette) self.lineEdit_Eqpt_Model.setObjectName(_fromUtf8("lineEdit_Eqpt_Model")) self.label_State = QtGui.QLabel(self.frame_Info_Panel) self.label_State.setGeometry(QtCore.QRect(10, 40, 111, 27)) self.label_State.setObjectName(_fromUtf8("label_State")) self.lineEdit_State = QtGui.QLineEdit(self.frame_Info_Panel) self.lineEdit_State.setEnabled(False) self.lineEdit_State.setGeometry(QtCore.QRect(120, 40, 111, 27)) palette = QtGui.QPalette() brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Text, brush) self.lineEdit_State.setPalette(palette) self.lineEdit_State.setObjectName(_fromUtf8("lineEdit_State")) self.groupBox_Current_Position = QtGui.QGroupBox(self.frame_Info_Panel) self.groupBox_Current_Position.setGeometry(QtCore.QRect(10, 70, 241, 91)) palette = QtGui.QPalette() brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.WindowText, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Button, brush) brush = QtGui.QBrush(QtGui.QColor(170, 255, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Light, brush) brush = QtGui.QBrush(QtGui.QColor(127, 255, 63)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Midlight, brush) brush = QtGui.QBrush(QtGui.QColor(42, 127, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Dark, brush) brush = QtGui.QBrush(QtGui.QColor(56, 170, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Mid, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 255)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.BrightText, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.ButtonText, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 255)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Base, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Window, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Shadow, brush) brush = QtGui.QBrush(QtGui.QColor(170, 255, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.AlternateBase, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 220)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.ToolTipBase, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.ToolTipText, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.WindowText, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Button, brush) brush = QtGui.QBrush(QtGui.QColor(170, 255, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Light, brush) brush = QtGui.QBrush(QtGui.QColor(127, 255, 63)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Midlight, brush) brush = QtGui.QBrush(QtGui.QColor(42, 127, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Dark, brush) brush = QtGui.QBrush(QtGui.QColor(56, 170, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Mid, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 255)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.BrightText, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.ButtonText, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 255)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Base, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Window, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Shadow, brush) brush = QtGui.QBrush(QtGui.QColor(170, 255, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.AlternateBase, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 220)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.ToolTipBase, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.ToolTipText, brush) brush = QtGui.QBrush(QtGui.QColor(42, 127, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.WindowText, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Button, brush) brush = QtGui.QBrush(QtGui.QColor(170, 255, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Light, brush) brush = QtGui.QBrush(QtGui.QColor(127, 255, 63)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Midlight, brush) brush = QtGui.QBrush(QtGui.QColor(42, 127, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Dark, brush) brush = QtGui.QBrush(QtGui.QColor(56, 170, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Mid, brush) brush = QtGui.QBrush(QtGui.QColor(42, 127, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 255)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.BrightText, brush) brush = QtGui.QBrush(QtGui.QColor(42, 127, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.ButtonText, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Base, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Window, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Shadow, brush) brush = QtGui.QBrush(QtGui.QColor(85, 255, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.AlternateBase, brush) brush = QtGui.QBrush(QtGui.QColor(255, 255, 220)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.ToolTipBase, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 0)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.ToolTipText, brush) self.groupBox_Current_Position.setPalette(palette) self.groupBox_Current_Position.setObjectName(_fromUtf8("groupBox_Current_Position")) self.label_Current_Position_X = QtGui.QLabel(self.groupBox_Current_Position) self.label_Current_Position_X.setGeometry(QtCore.QRect(20, 20, 41, 27)) self.label_Current_Position_X.setObjectName(_fromUtf8("label_Current_Position_X")) self.lineEdit_Current_Position_X = QtGui.QLineEdit(self.groupBox_Current_Position) self.lineEdit_Current_Position_X.setEnabled(False) self.lineEdit_Current_Position_X.setGeometry(QtCore.QRect(60, 20, 161, 27)) palette = QtGui.QPalette() brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Text, brush) self.lineEdit_Current_Position_X.setPalette(palette) self.lineEdit_Current_Position_X.setObjectName(_fromUtf8("lineEdit_Current_Position_X")) self.label_Current_Position_Y = QtGui.QLabel(self.groupBox_Current_Position) self.label_Current_Position_Y.setGeometry(QtCore.QRect(20, 50, 41, 27)) self.label_Current_Position_Y.setObjectName(_fromUtf8("label_Current_Position_Y")) self.lineEdit_Current_Position_Y = QtGui.QLineEdit(self.groupBox_Current_Position) self.lineEdit_Current_Position_Y.setEnabled(False) self.lineEdit_Current_Position_Y.setGeometry(QtCore.QRect(60, 50, 161, 27)) palette = QtGui.QPalette() brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Active, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(60, 60, 60)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Inactive, QtGui.QPalette.Text, brush) brush = QtGui.QBrush(QtGui.QColor(0, 0, 127)) brush.setStyle(QtCore.Qt.SolidPattern) palette.setBrush(QtGui.QPalette.Disabled, QtGui.QPalette.Text, brush) self.lineEdit_Current_Position_Y.setPalette(palette) self.lineEdit_Current_Position_Y.setObjectName(_fromUtf8("lineEdit_Current_Position_Y")) self.scrollArea_Info_Panel.setWidget(self.scrollAreaWidgetContents) self.tabWidget_Info_Panel.addTab(self.tab_1, _fromUtf8("")) self.tab_2 = QtGui.QWidget() self.tab_2.setObjectName(_fromUtf8("tab_2")) self.tabWidget_Info_Panel.addTab(self.tab_2, _fromUtf8("")) self.dockWidget_Info_Panel.setWidget(self.dockWidgetContents_Info_Panel) MainWindow_InfoPanel.addDockWidget(QtCore.Qt.DockWidgetArea(2), self.dockWidget_Info_Panel) self.retranslateUi(MainWindow_InfoPanel) self.tabWidget_Info_Panel.setCurrentIndex(0) QtCore.QMetaObject.connectSlotsByName(MainWindow_InfoPanel) def retranslateUi(self, MainWindow_InfoPanel): MainWindow_InfoPanel.setWindowTitle(QtGui.QApplication.translate("MainWindow_InfoPanel", "MainWindow Info Panel", None, QtGui.QApplication.UnicodeUTF8)) self.dockWidget_Info_Panel.setWindowTitle(QtGui.QApplication.translate("MainWindow_InfoPanel", "Info Panel", None, QtGui.QApplication.UnicodeUTF8)) self.label_Eqpt_Model.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "Eqpt Model:", None, QtGui.QApplication.UnicodeUTF8)) self.lineEdit_Eqpt_Model.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "ABC", None, QtGui.QApplication.UnicodeUTF8)) self.label_State.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "State:", None, QtGui.QApplication.UnicodeUTF8)) self.lineEdit_State.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "Working", None, QtGui.QApplication.UnicodeUTF8)) self.groupBox_Current_Position.setTitle(QtGui.QApplication.translate("MainWindow_InfoPanel", "Current Position:", None, QtGui.QApplication.UnicodeUTF8)) self.label_Current_Position_X.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "X =", None, QtGui.QApplication.UnicodeUTF8)) self.lineEdit_Current_Position_X.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "1000.00 m", None, QtGui.QApplication.UnicodeUTF8)) self.label_Current_Position_Y.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "Y =", None, QtGui.QApplication.UnicodeUTF8)) self.lineEdit_Current_Position_Y.setText(QtGui.QApplication.translate("MainWindow_InfoPanel", "1000.00 m", None, QtGui.QApplication.UnicodeUTF8)) self.tabWidget_Info_Panel.setTabText(self.tabWidget_Info_Panel.indexOf(self.tab_1), QtGui.QApplication.translate("MainWindow_InfoPanel", "Info_Pg 1", None, QtGui.QApplication.UnicodeUTF8)) self.tabWidget_Info_Panel.setTabText(self.tabWidget_Info_Panel.indexOf(self.tab_2), QtGui.QApplication.translate("MainWindow_InfoPanel", "Info_Pg 2", None, QtGui.QApplication.UnicodeUTF8)) PS: I initially created the mainWindow as a Dialog, but realized that after undock & redock, the dockWidget doesn't dock properly. Somehow there's an offset. This doesn't seem to be a problem if the mainWindow is a QtGui.QMainWindow instead of a QtGui.QDialog.

  Read the article

• What are good design practices when working with Entity Framework

  - by AD

  This will apply mostly for an asp.net application where the data is not accessed via soa. Meaning that you get access to the objects loaded from the framework, not Transfer Objects, although some recommendation still apply. This is a community post, so please add to it as you see fit. Applies to: Entity Framework 1.0 shipped with Visual Studio 2008 sp1. Why pick EF in the first place? Considering it is a young technology with plenty of problems (see below), it may be a hard sell to get on the EF bandwagon for your project. However, it is the technology Microsoft is pushing (at the expense of Linq2Sql, which is a subset of EF). In addition, you may not be satisfied with NHibernate or other solutions out there. Whatever the reasons, there are people out there (including me) working with EF and life is not bad.make you think. EF and inheritance The first big subject is inheritance. EF does support mapping for inherited classes that are persisted in 2 ways: table per class and table the hierarchy. The modeling is easy and there are no programming issues with that part. (The following applies to table per class model as I don't have experience with table per hierarchy, which is, anyway, limited.) The real problem comes when you are trying to run queries that include one or many objects that are part of an inheritance tree: the generated sql is incredibly awful, takes a long time to get parsed by the EF and takes a long time to execute as well. This is a real show stopper. Enough that EF should probably not be used with inheritance or as little as possible. Here is an example of how bad it was. My EF model had ~30 classes, ~10 of which were part of an inheritance tree. On running a query to get one item from the Base class, something as simple as Base.Get(id), the generated SQL was over 50,000 characters. Then when you are trying to return some Associations, it degenerates even more, going as far as throwing SQL exceptions about not being able to query more than 256 tables at once. Ok, this is bad, EF concept is to allow you to create your object structure without (or with as little as possible) consideration on the actual database implementation of your table. It completely fails at this. So, recommendations? Avoid inheritance if you can, the performance will be so much better. Use it sparingly where you have to. In my opinion, this makes EF a glorified sql-generation tool for querying, but there are still advantages to using it. And ways to implement mechanism that are similar to inheritance. Bypassing inheritance with Interfaces First thing to know with trying to get some kind of inheritance going with EF is that you cannot assign a non-EF-modeled class a base class. Don't even try it, it will get overwritten by the modeler. So what to do? You can use interfaces to enforce that classes implement some functionality. For example here is a IEntity interface that allow you to define Associations between EF entities where you don't know at design time what the type of the entity would be. public enum EntityTypes{ Unknown = -1, Dog = 0, Cat } public interface IEntity { int EntityID { get; } string Name { get; } Type EntityType { get; } } public partial class Dog : IEntity { // implement EntityID and Name which could actually be fields // from your EF model Type EntityType{ get{ return EntityTypes.Dog; } } } Using this IEntity, you can then work with undefined associations in other classes // lets take a class that you defined in your model. // that class has a mapping to the columns: PetID, PetType public partial class Person { public IEntity GetPet() { return IEntityController.Get(PetID,PetType); } } which makes use of some extension functions: public class IEntityController { static public IEntity Get(int id, EntityTypes type) { switch (type) { case EntityTypes.Dog: return Dog.Get(id); case EntityTypes.Cat: return Cat.Get(id); default: throw new Exception("Invalid EntityType"); } } } Not as neat as having plain inheritance, particularly considering you have to store the PetType in an extra database field, but considering the performance gains, I would not look back. It also cannot model one-to-many, many-to-many relationship, but with creative uses of 'Union' it could be made to work. Finally, it creates the side effet of loading data in a property/function of the object, which you need to be careful about. Using a clear naming convention like GetXYZ() helps in that regards. Compiled Queries Entity Framework performance is not as good as direct database access with ADO (obviously) or Linq2SQL. There are ways to improve it however, one of which is compiling your queries. The performance of a compiled query is similar to Linq2Sql. What is a compiled query? It is simply a query for which you tell the framework to keep the parsed tree in memory so it doesn't need to be regenerated the next time you run it. So the next run, you will save the time it takes to parse the tree. Do not discount that as it is a very costly operation that gets even worse with more complex queries. There are 2 ways to compile a query: creating an ObjectQuery with EntitySQL and using CompiledQuery.Compile() function. (Note that by using an EntityDataSource in your page, you will in fact be using ObjectQuery with EntitySQL, so that gets compiled and cached). An aside here in case you don't know what EntitySQL is. It is a string-based way of writing queries against the EF. Here is an example: "select value dog from Entities.DogSet as dog where dog.ID = @ID". The syntax is pretty similar to SQL syntax. You can also do pretty complex object manipulation, which is well explained [here][1]. Ok, so here is how to do it using ObjectQuery< string query = "select value dog " + "from Entities.DogSet as dog " + "where dog.ID = @ID"; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>(query, EntityContext.Instance)); oQuery.Parameters.Add(new ObjectParameter("ID", id)); oQuery.EnablePlanCaching = true; return oQuery.FirstOrDefault(); The first time you run this query, the framework will generate the expression tree and keep it in memory. So the next time it gets executed, you will save on that costly step. In that example EnablePlanCaching = true, which is unnecessary since that is the default option. The other way to compile a query for later use is the CompiledQuery.Compile method. This uses a delegate: static readonly Func<Entities, int, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, Dog>((ctx, id) => ctx.DogSet.FirstOrDefault(it => it.ID == id)); or using linq static readonly Func<Entities, int, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, Dog>((ctx, id) => (from dog in ctx.DogSet where dog.ID == id select dog).FirstOrDefault()); to call the query: query_GetDog.Invoke( YourContext, id ); The advantage of CompiledQuery is that the syntax of your query is checked at compile time, where as EntitySQL is not. However, there are other consideration... Includes Lets say you want to have the data for the dog owner to be returned by the query to avoid making 2 calls to the database. Easy to do, right? EntitySQL string query = "select value dog " + "from Entities.DogSet as dog " + "where dog.ID = @ID"; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>(query, EntityContext.Instance)).Include("Owner"); oQuery.Parameters.Add(new ObjectParameter("ID", id)); oQuery.EnablePlanCaching = true; return oQuery.FirstOrDefault(); CompiledQuery static readonly Func<Entities, int, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, Dog>((ctx, id) => (from dog in ctx.DogSet.Include("Owner") where dog.ID == id select dog).FirstOrDefault()); Now, what if you want to have the Include parametrized? What I mean is that you want to have a single Get() function that is called from different pages that care about different relationships for the dog. One cares about the Owner, another about his FavoriteFood, another about his FavotireToy and so on. Basicly, you want to tell the query which associations to load. It is easy to do with EntitySQL public Dog Get(int id, string include) { string query = "select value dog " + "from Entities.DogSet as dog " + "where dog.ID = @ID"; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>(query, EntityContext.Instance)) .IncludeMany(include); oQuery.Parameters.Add(new ObjectParameter("ID", id)); oQuery.EnablePlanCaching = true; return oQuery.FirstOrDefault(); } The include simply uses the passed string. Easy enough. Note that it is possible to improve on the Include(string) function (that accepts only a single path) with an IncludeMany(string) that will let you pass a string of comma-separated associations to load. Look further in the extension section for this function. If we try to do it with CompiledQuery however, we run into numerous problems: The obvious static readonly Func<Entities, int, string, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, string, Dog>((ctx, id, include) => (from dog in ctx.DogSet.Include(include) where dog.ID == id select dog).FirstOrDefault()); will choke when called with: query_GetDog.Invoke( YourContext, id, "Owner,FavoriteFood" ); Because, as mentionned above, Include() only wants to see a single path in the string and here we are giving it 2: "Owner" and "FavoriteFood" (which is not to be confused with "Owner.FavoriteFood"!). Then, let's use IncludeMany(), which is an extension function static readonly Func<Entities, int, string, Dog> query_GetDog = CompiledQuery.Compile<Entities, int, string, Dog>((ctx, id, include) => (from dog in ctx.DogSet.IncludeMany(include) where dog.ID == id select dog).FirstOrDefault()); Wrong again, this time it is because the EF cannot parse IncludeMany because it is not part of the functions that is recognizes: it is an extension. Ok, so you want to pass an arbitrary number of paths to your function and Includes() only takes a single one. What to do? You could decide that you will never ever need more than, say 20 Includes, and pass each separated strings in a struct to CompiledQuery. But now the query looks like this: from dog in ctx.DogSet.Include(include1).Include(include2).Include(include3) .Include(include4).Include(include5).Include(include6) .[...].Include(include19).Include(include20) where dog.ID == id select dog which is awful as well. Ok, then, but wait a minute. Can't we return an ObjectQuery< with CompiledQuery? Then set the includes on that? Well, that what I would have thought so as well: static readonly Func<Entities, int, ObjectQuery<Dog>> query_GetDog = CompiledQuery.Compile<Entities, int, string, ObjectQuery<Dog>>((ctx, id) => (ObjectQuery<Dog>)(from dog in ctx.DogSet where dog.ID == id select dog)); public Dog GetDog( int id, string include ) { ObjectQuery<Dog> oQuery = query_GetDog(id); oQuery = oQuery.IncludeMany(include); return oQuery.FirstOrDefault; } That should have worked, except that when you call IncludeMany (or Include, Where, OrderBy...) you invalidate the cached compiled query because it is an entirely new one now! So, the expression tree needs to be reparsed and you get that performance hit again. So what is the solution? You simply cannot use CompiledQueries with parametrized Includes. Use EntitySQL instead. This doesn't mean that there aren't uses for CompiledQueries. It is great for localized queries that will always be called in the same context. Ideally CompiledQuery should always be used because the syntax is checked at compile time, but due to limitation, that's not possible. An example of use would be: you may want to have a page that queries which two dogs have the same favorite food, which is a bit narrow for a BusinessLayer function, so you put it in your page and know exactly what type of includes are required. Passing more than 3 parameters to a CompiledQuery Func is limited to 5 parameters, of which the last one is the return type and the first one is your Entities object from the model. So that leaves you with 3 parameters. A pitance, but it can be improved on very easily. public struct MyParams { public string param1; public int param2; public DateTime param3; } static readonly Func<Entities, MyParams, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, MyParams, IEnumerable<Dog>>((ctx, myParams) => from dog in ctx.DogSet where dog.Age == myParams.param2 && dog.Name == myParams.param1 and dog.BirthDate > myParams.param3 select dog); public List<Dog> GetSomeDogs( int age, string Name, DateTime birthDate ) { MyParams myParams = new MyParams(); myParams.param1 = name; myParams.param2 = age; myParams.param3 = birthDate; return query_GetDog(YourContext,myParams).ToList(); } Return Types (this does not apply to EntitySQL queries as they aren't compiled at the same time during execution as the CompiledQuery method) Working with Linq, you usually don't force the execution of the query until the very last moment, in case some other functions downstream wants to change the query in some way: static readonly Func<Entities, int, string, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, int, string, IEnumerable<Dog>>((ctx, age, name) => from dog in ctx.DogSet where dog.Age == age && dog.Name == name select dog); public IEnumerable<Dog> GetSomeDogs( int age, string name ) { return query_GetDog(YourContext,age,name); } public void DataBindStuff() { IEnumerable<Dog> dogs = GetSomeDogs(4,"Bud"); // but I want the dogs ordered by BirthDate gridView.DataSource = dogs.OrderBy( it => it.BirthDate ); } What is going to happen here? By still playing with the original ObjectQuery (that is the actual return type of the Linq statement, which implements IEnumerable), it will invalidate the compiled query and be force to re-parse. So, the rule of thumb is to return a List< of objects instead. static readonly Func<Entities, int, string, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, int, string, IEnumerable<Dog>>((ctx, age, name) => from dog in ctx.DogSet where dog.Age == age && dog.Name == name select dog); public List<Dog> GetSomeDogs( int age, string name ) { return query_GetDog(YourContext,age,name).ToList(); //<== change here } public void DataBindStuff() { List<Dog> dogs = GetSomeDogs(4,"Bud"); // but I want the dogs ordered by BirthDate gridView.DataSource = dogs.OrderBy( it => it.BirthDate ); } When you call ToList(), the query gets executed as per the compiled query and then, later, the OrderBy is executed against the objects in memory. It may be a little bit slower, but I'm not even sure. One sure thing is that you have no worries about mis-handling the ObjectQuery and invalidating the compiled query plan. Once again, that is not a blanket statement. ToList() is a defensive programming trick, but if you have a valid reason not to use ToList(), go ahead. There are many cases in which you would want to refine the query before executing it. Performance What is the performance impact of compiling a query? It can actually be fairly large. A rule of thumb is that compiling and caching the query for reuse takes at least double the time of simply executing it without caching. For complex queries (read inherirante), I have seen upwards to 10 seconds. So, the first time a pre-compiled query gets called, you get a performance hit. After that first hit, performance is noticeably better than the same non-pre-compiled query. Practically the same as Linq2Sql When you load a page with pre-compiled queries the first time you will get a hit. It will load in maybe 5-15 seconds (obviously more than one pre-compiled queries will end up being called), while subsequent loads will take less than 300ms. Dramatic difference, and it is up to you to decide if it is ok for your first user to take a hit or you want a script to call your pages to force a compilation of the queries. Can this query be cached? { Dog dog = from dog in YourContext.DogSet where dog.ID == id select dog; } No, ad-hoc Linq queries are not cached and you will incur the cost of generating the tree every single time you call it. Parametrized Queries Most search capabilities involve heavily parametrized queries. There are even libraries available that will let you build a parametrized query out of lamba expressions. The problem is that you cannot use pre-compiled queries with those. One way around that is to map out all the possible criteria in the query and flag which one you want to use: public struct MyParams { public string name; public bool checkName; public int age; public bool checkAge; } static readonly Func<Entities, MyParams, IEnumerable<Dog>> query_GetDog = CompiledQuery.Compile<Entities, MyParams, IEnumerable<Dog>>((ctx, myParams) => from dog in ctx.DogSet where (myParams.checkAge == true && dog.Age == myParams.age) && (myParams.checkName == true && dog.Name == myParams.name ) select dog); protected List<Dog> GetSomeDogs() { MyParams myParams = new MyParams(); myParams.name = "Bud"; myParams.checkName = true; myParams.age = 0; myParams.checkAge = false; return query_GetDog(YourContext,myParams).ToList(); } The advantage here is that you get all the benifits of a pre-compiled quert. The disadvantages are that you most likely will end up with a where clause that is pretty difficult to maintain, that you will incur a bigger penalty for pre-compiling the query and that each query you run is not as efficient as it could be (particularly with joins thrown in). Another way is to build an EntitySQL query piece by piece, like we all did with SQL. protected List<Dod> GetSomeDogs( string name, int age) { string query = "select value dog from Entities.DogSet where 1 = 1 "; if( !String.IsNullOrEmpty(name) ) query = query + " and dog.Name == @Name "; if( age > 0 ) query = query + " and dog.Age == @Age "; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>( query, YourContext ); if( !String.IsNullOrEmpty(name) ) oQuery.Parameters.Add( new ObjectParameter( "Name", name ) ); if( age > 0 ) oQuery.Parameters.Add( new ObjectParameter( "Age", age ) ); return oQuery.ToList(); } Here the problems are: - there is no syntax checking during compilation - each different combination of parameters generate a different query which will need to be pre-compiled when it is first run. In this case, there are only 4 different possible queries (no params, age-only, name-only and both params), but you can see that there can be way more with a normal world search. - Noone likes to concatenate strings! Another option is to query a large subset of the data and then narrow it down in memory. This is particularly useful if you are working with a definite subset of the data, like all the dogs in a city. You know there are a lot but you also know there aren't that many... so your CityDog search page can load all the dogs for the city in memory, which is a single pre-compiled query and then refine the results protected List<Dod> GetSomeDogs( string name, int age, string city) { string query = "select value dog from Entities.DogSet where dog.Owner.Address.City == @City "; ObjectQuery<Dog> oQuery = new ObjectQuery<Dog>( query, YourContext ); oQuery.Parameters.Add( new ObjectParameter( "City", city ) ); List<Dog> dogs = oQuery.ToList(); if( !String.IsNullOrEmpty(name) ) dogs = dogs.Where( it => it.Name == name ); if( age > 0 ) dogs = dogs.Where( it => it.Age == age ); return dogs; } It is particularly useful when you start displaying all the data then allow for filtering. Problems: - Could lead to serious data transfer if you are not careful about your subset. - You can only filter on the data that you returned. It means that if you don't return the Dog.Owner association, you will not be able to filter on the Dog.Owner.Name So what is the best solution? There isn't any. You need to pick the solution that works best for you and your problem: - Use lambda-based query building when you don't care about pre-compiling your queries. - Use fully-defined pre-compiled Linq query when your object structure is not too complex. - Use EntitySQL/string concatenation when the structure could be complex and when the possible number of different resulting queries are small (which means fewer pre-compilation hits). - Use in-memory filtering when you are working with a smallish subset of the data or when you had to fetch all of the data on the data at first anyway (if the performance is fine with all the data, then filtering in memory will not cause any time to be spent in the db). Singleton access The best way to deal with your context and entities accross all your pages is to use the singleton pattern: public sealed class YourContext { private const string instanceKey = "On3GoModelKey"; YourContext(){} public static YourEntities Instance { get { HttpContext context = HttpContext.Current; if( context == null ) return Nested.instance; if (context.Items[instanceKey] == null) { On3GoEntities entity = new On3GoEntities(); context.Items[instanceKey] = entity; } return (YourEntities)context.Items[instanceKey]; } } class Nested { // Explicit static constructor to tell C# compiler // not to mark type as beforefieldinit static Nested() { } internal static readonly YourEntities instance = new YourEntities(); } } NoTracking, is it worth it? When executing a query, you can tell the framework to track the objects it will return or not. What does it mean? With tracking enabled (the default option), the framework will track what is going on with the object (has it been modified? Created? Deleted?) and will also link objects together, when further queries are made from the database, which is what is of interest here. For example, lets assume that Dog with ID == 2 has an owner which ID == 10. Dog dog = (from dog in YourContext.DogSet where dog.ID == 2 select dog).FirstOrDefault(); //dog.OwnerReference.IsLoaded == false; Person owner = (from o in YourContext.PersonSet where o.ID == 10 select dog).FirstOrDefault(); //dog.OwnerReference.IsLoaded == true; If we were to do the same with no tracking, the result would be different. ObjectQuery<Dog> oDogQuery = (ObjectQuery<Dog>) (from dog in YourContext.DogSet where dog.ID == 2 select dog); oDogQuery.MergeOption = MergeOption.NoTracking; Dog dog = oDogQuery.FirstOrDefault(); //dog.OwnerReference.IsLoaded == false; ObjectQuery<Person> oPersonQuery = (ObjectQuery<Person>) (from o in YourContext.PersonSet where o.ID == 10 select o); oPersonQuery.MergeOption = MergeOption.NoTracking; Owner owner = oPersonQuery.FirstOrDefault(); //dog.OwnerReference.IsLoaded == false; Tracking is very useful and in a perfect world without performance issue, it would always be on. But in this world, there is a price for it, in terms of performance. So, should you use NoTracking to speed things up? It depends on what you are planning to use the data for. Is there any chance that the data your query with NoTracking can be used to make update/insert/delete in the database? If so, don't use NoTracking because associations are not tracked and will causes exceptions to be thrown. In a page where there are absolutly no updates to the database, you can use NoTracking. Mixing tracking and NoTracking is possible, but it requires you to be extra careful with updates/inserts/deletes. The problem is that if you mix then you risk having the framework trying to Attach() a NoTracking object to the context where another copy of the same object exist with tracking on. Basicly, what I am saying is that Dog dog1 = (from dog in YourContext.DogSet where dog.ID == 2).FirstOrDefault(); ObjectQuery<Dog> oDogQuery = (ObjectQuery<Dog>) (from dog in YourContext.DogSet where dog.ID == 2 select dog); oDogQuery.MergeOption = MergeOption.NoTracking; Dog dog2 = oDogQuery.FirstOrDefault(); dog1 and dog2 are 2 different objects, one tracked and one not. Using the detached object in an update/insert will force an Attach() that will say "Wait a minute, I do already have an object here with the same database key. Fail". And when you Attach() one object, all of its hierarchy gets attached as well, causing problems everywhere. Be extra careful. How much faster is it with NoTracking It depends on the queries. Some are much more succeptible to tracking than other. I don't have a fast an easy rule for it, but it helps. So I should use NoTracking everywhere then? Not exactly. There are some advantages to tracking object. The first one is that the object is cached, so subsequent call for that object will not hit the database. That cache is only valid for the lifetime of the YourEntities object, which, if you use the singleton code above, is the same as the page lifetime. One page request == one YourEntity object. So for multiple calls for the same object, it will load only once per page request. (Other caching mechanism could extend that). What happens when you are using NoTracking and try to load the same object multiple times? The database will be queried each time, so there is an impact there. How often do/should you call for the same object during a single page request? As little as possible of course, but it does happens. Also remember the piece above about having the associations connected automatically for your? You don't have that with NoTracking, so if you load your data in multiple batches, you will not have a link to between them: ObjectQuery<Dog> oDogQuery = (ObjectQuery<Dog>)(from dog in YourContext.DogSet select dog); oDogQuery.MergeOption = MergeOption.NoTracking; List<Dog> dogs = oDogQuery.ToList(); ObjectQuery<Person> oPersonQuery = (ObjectQuery<Person>)(from o in YourContext.PersonSet select o); oPersonQuery.MergeOption = MergeOption.NoTracking; List<Person> owners = oPersonQuery.ToList(); In this case, no dog will have its .Owner property set. Some things to keep in mind when you are trying to optimize the performance. No lazy loading, what am I to do? This can be seen as a blessing in disguise. Of course it is annoying to load everything manually. However, it decreases the number of calls to the db and forces you to think about when you should load data. The more you can load in one database call the better. That was always true, but it is enforced now with this 'feature' of EF. Of course, you can call if( !ObjectReference.IsLoaded ) ObjectReference.Load(); if you want to, but a better practice is to force the framework to load the objects you know you will need in one shot. This is where the discussion about parametrized Includes begins to make sense. Lets say you have you Dog object public class Dog { public Dog Get(int id) { return YourContext.DogSet.FirstOrDefault(it => it.ID == id ); } } This is the type of function you work with all the time. It gets called from all over the place and once you have that Dog object, you will do very different things to it in different functions. First, it should be pre-compiled, because you will call that very often. Second, each different pages will want to have access to a different subset of the Dog data. Some will want the Owner, some the FavoriteToy, etc. Of course, you could call Load() for each reference you need anytime you need one. But that will generate a call to the database each time. Bad idea. So instead, each page will ask for the data it wants to see when it first request for the Dog object: static public Dog Get(int id) { return GetDog(entity,"");} static public Dog Get(int id, string includePath) { string query = "select value o " + " from YourEntities.DogSet as o " +

  Read the article

< Previous Page | 36 37 38 39 40