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  • On the search for my next great .Net Read

    - by user127954
    Just got done with "The art of unit testing". It was a great read and i think everyone should go buy a copy. With that said i think the next book I'm like to read would be a architecture / Design type book that would focus heavily on building your objects / software in such a way that it would be: Low Coupling High Cohesion Easily Maintainable / Extended Easy to test Easy to Navigate / Debug The above characteristcs are the most important ones but also maybe it would also include (but not necessary) designing for: Performance - Don't want to design a system at at the end find out its dog slow :) Scalability - Again don't want to design something at the end find out it won't scale. I'd also prefer (but not necessary again): Something newer - Architectural principles seem to gradually evolve / improve over time and id like something with current thinking. .Net as illustrating language - like i said above its not mandatory but since its what i use every day id prefer it to be in .net. Doesn't really matter if its in vb.net or c# Some of the topics that would be talked about its how to minimize dependencies and using interfaces throughout your solution rather than concrete classes. Maybe it would constract /compare some of the newest design principles like DDD, Repository Pattern, Ect... I already have "Clean Code" (don't know if its this type of book or not) and "Working effectively with legacy code" on my radar but id like to read a book based upon the topic i talked about above first. Is there such a book?

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  • How do I write this SQL statement to get the ad and posting? (PHP/MySQL)

    - by ggfan
    I am a little confused on the logic of how to write this SQL statement. When a user clicks on a tag, say HTML, it would display all the posts with HTML as its tag. (a post can have multiple tags) I have three tables: Posting--posting_id, title, detail, etc tags--tagID, tagname postingtag--posting_id, tagID I want to display all the title of the post and the date added. global $dbc; $tagID=$_GET['tagID']; //the GET is set by URL //part I need help with. I need another WHERE statment to get to the posting table $query = "SELECT p.title,p.date_added, t.tagname FROM posting as p, postingtag as pt, tags as t WHERE t.tagID=$tagID"; $data = mysqli_query($dbc, $query); echo '<table>'; echo '<tr><td><b>Title</b></td><td><b>Date Posted</b></td></tr>'; while ($row = mysqli_fetch_array($data)) { echo '<tr><td>'.$row['title'].'</td>'; echo '<td>'.$row['date_added'].'</td></tr>'; } echo '</table>'; }

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  • StackPanel loded is not getting fired in.cs page

    - by prince23
    <sdk:DataGridTemplateColumn> <sdk:DataGridTemplateColumn.CellTemplate> <DataTemplate> <StackPanel Loaded ="SPImage_Loaded" Orientation="Horizontal" Background="Transparent" > <Button x:Name="myButton" Click="Btn_Click"> <Image x:Name="imgMarks" " Stretch="None"/> </Button> </StackPanel> </DataTemplate> </sdk:DataGridTemplateColumn.CellTemplate> </sdk:DataGridTemplateColumn> in .cs i have defined the event for stack panel private void SPImage_Loaded(object sender, RoutedEventArgs e) { try { var TargetMarks = sender as StackPanel; Image imgMarks= (Image)TargetScore.FindName("imgMarks"); Marks obj = (Marks )TargetMarks.DataContext; // here marks oject would be containg the details // here if marks.score object value is 1 then bind the image //else // dnt bind the image . that is logic i am trying to do. imgMarks.Source = new BitmapImage(new Uri("/Images/a1.png", UriKind.Relative)); } catch (Exception) { throw; } } any solution on this would be great. is there any better solution to achive this. plz help me out. thank you.

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  • Error while reading custom configuration file(app.config)

    - by Newbie
    I am making a custom configuration in my winform application. (It will represent a country-corrency list) First the CountryList class namespace UtilityMethods { public class CountryList : ConfigurationSection { public CountryList() { // // TODO: Add constructor logic here // } [ConfigurationProperty("CountryCurrency", IsRequired = true)] public Hashtable CountryCurrencies { get { return CountryCurrency.GetCountryCurrency(); } } } } The GetCountryCurrency() method is defined in CountryCurrency class as under namespace UtilityMethods { public static class CountryCurrency { public static Hashtable GetCountryCurrency() { Hashtable ht = new Hashtable(); ht.Add("India", "Rupees"); ht.Add("USA", "Dollar"); return ht; } } } The app.config file looks like <?xml version="1.0" encoding="utf-8" ?> <configuration> <configSections> <section name ="CountryList1" type ="UtilityMethods.CountryList,CountryList,Version=2.0.0.0, Culture=neutral"/> </configSections> <appSettings /> </configuration> And I am calling this from a button_click's event as try { CountryList cList = ConfigurationManager.GetSection("CountryList") as CountryList; Hashtable ht = cList.CountryCurrencies; } catch (Exception ex) { string h = ex.Message; } Upon running the application and clicking on the button I am getting this error Could not load type 'UtilityMethods.CountryList' from assembly 'System.Configuration, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' Please help (dotnet framework : 3.5 Language: C#)

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  • Optimally place a pie slice in a rectangle.

    - by Lisa
    Given a rectangle (w, h) and a pie slice with start angle and end angle, how can I place the slice optimally in the rectangle so that it fills the room best (from an optical point of view, not mathematically speaking)? I'm currently placing the pie slice's center in the center of the rectangle and use the half of the smaller of both rectangle sides as the radius. This leaves plenty of room for certain configurations. Examples to make clear what I'm after, based on the precondition that the slice is drawn like a unit circle: A start angle of 0 and an end angle of PI would lead to a filled lower half of the rectangle and an empty upper half. A good solution here would be to move the center up by 1/4*h. A start angle of 0 and an end angle of PI/2 would lead to a filled bottom right quarter of the rectangle. A good solution here would be to move the center point to the top left of the rectangle and to set the radius to the smaller of both rectangle sides. This is fairly easy for the cases I've sketched but it becomes complicated when the start and end angles are arbitrary. I am searching for an algorithm which determines center of the slice and radius in a way that fills the rectangle best. Pseudo code would be great since I'm not a big mathematician.

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  • Can I use Eclipse JDT to create new 'working copies' of source files in memory only?

    - by RYates
    I'm using Eclipse JDT to build a Java refactoring platform, for exploring different refactorings in memory before choosing one and saving it. I can create collections of working copies of the source files, edit them in memory, and commit the changes to disk using the JDT framework. However, I also want to generate new 'working copy' source files in memory as part of refactorings, and only create the corresponding real source file if I commit the working copy. I have seen various hints that this is possible, e.g. http://www.jarvana.com/jarvana/view/org/eclipse/jdt/doc/isv/3.3.0-v20070613/isv-3.3.0-v20070613.jar!/guide/jdt%5Fapi%5Fmanip.htm says "Note that the compilation unit does not need to exist in the Java model in order for a working copy to be created". So far I have only been able to create a new real file, i.e. ICompilationUnit newICompilationUnit = myPackage.createCompilationUnit(newName, "package piffle; public class Baz{private int i=0;}", false, null); This is not what I want. Does anyone know how to create a new 'working copy' source file, that does not appear in my file system until I commit it? Or any other mechanism to achieve the same thing?

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  • Android lifecycle of thread-based game

    - by ehehhh
    I ran into a bit of trouble while trying to get my game to work correctly after being put to the background by the user or a phone call for example. My app has a SurfaceView class called GameView, which has the onDraw() method to do all the necessary drawing for my game and two threads - one for calling the onDraw() and one for doing the necessary calculations for the game's logic. I succesfully implemented onPause() and onResume(). (I paused both threads when back button was pressed and resumed them after user cancelled in the AlertDialog.) Now I would like to have the game paused the same way when onStop() gets called. I put both threads on pause and saved my characters location in the savedInstanceState, but when I start my app again, no method gets called (I checked with Logcat). I believe onRestart() should be called first, then onStart() and then onResume(), but none of that happens. What am I doing wrong? (Didn't include any code, because it seems to be a problem of me not understanding the lifecycle, not a problem in code. If it seems necessary, I'll post the parts you request.)

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  • Strategies for dealing with Circular references caused by JPA relationships?

    - by ams
    I am trying to partition my application into modules by features packaged into separate jars such as feature-a.jar, feature-b.jar, ... etc. Individual feature jars such as feature-a.jar should contain all the code for a feature a including jpa entities, business logic, rest apis, unit tests, integration test ... etc. The problem I am running into is that bi-directional relationships between JPA entities cause circular references between the jar files. For example Customer entity should be in customer.jar and the Order should be in order.jar but Customer references order and order references customer making it hard to split them into separate jars / eclipse projects. Options I see for dealing with the circular dependencies in JPA entities: Option 1: Put all the entities into one jar / one project Option 2: Don't map certain bi-directianl relationships to avoid circular dependencies across projects. Questions: What rules / principles have you used to decide when to do bi-directional mapping vs. not? Have you been able to break jpa entities into their own projects / jar by features if so how did you avoid the circular dependencies issues?

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  • What single software development tool do you think holds the most value?

    - by Phobis
    Every day I realize how much I love Visual Studio for .NET development.... but, I believe that Resharper, may hold a value that surpasses Visual Studio's (I am using VS 2005 for WPF/WCF development). I decided it would be great to compile a list of the most valuable tools for software development. These can be applications/plug-ins anything that you think holds GREAT value. Also, please explain the benefits of the tool that you are posting. Resharper: Intergrated Unit testing "Camel Hump" code auto completion Find "usings" (inverse of "Go to Deceleration") Code formating and member rearranging Assembly and namespace inclusion (based on your code) Check for common optimizations and possible bugs in code and suggests/rewrites the code for you (things like null checking, redundant delegate creation, inverting if statements, etc...); Tells you when code and be more generic (may suggest things like "use this interface instead" if your code never refers to something specific on an object) Helps you see code that is not being used and will clean any unused members. File structure view helps you jump around the regions of your file (this is really awesome and clean). Class searching (you can use things like camel humps) Asks you which partial file to open once you find a class. It also has it's own plugin support, so you can do things like FxCop, documentation and relfector (all free). This thing has so much I don't think I hit 10% of it yet :) [When I get time, I will try to add more... feel free to help me out]

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  • Request for advice about class design, inheritance/aggregation

    - by Lasse V. Karlsen
    I have started writing my own WebDAV server class in .NET, and the first class I'm starting with is a WebDAVListener class, modelled after how the HttpListener class works. Since I don't want to reimplement the core http protocol handling, I will use HttpListener for all its worth, and thus I have a question. What would the suggested way be to handle this: Implement all the methods and properties found inside HttpListener, just changing the class types where it matters (ie. the GetContext + EndGetContext methods would return a different class for WebDAV contexts), and storing and using a HttpListener object internally Construct WebDAVListener by passing it a HttpListener class to use? Create a wrapper for HttpListener with an interface, and constrct WebDAVListener by passing it an object implementing this interface? If going the route of passing a HttpListener (disguised or otherwise) to the WebDAVListener, would you expose the underlying listener object through a property, or would you expect the program that used the class to keep a reference to the underlying HttpListener? Also, in this case, would you expose some of the methods of HttpListener through the WebDAVListener, like Start and Stop, or would you again expect the program that used it to keep the HttpListener reference around for all those things? My initial reaction tells me that I want a combination. For one thing, I would like my WebDAVListener class to look like a complete implementation, hiding the fact that there is a HttpListener object beneath it. On the other hand, I would like to build unit-tests without actually spinning up a networked server, so some kind of mocking ability would be nice to have as well, which suggests I would like the interface-wrapper way. One way I could solve this would be this: public WebDAVListener() : WebDAVListener(new HttpListenerWrapper()) { } public WebDAVListener(IHttpListenerWrapper listener) { } And then I would implement all the methods of HttpListener (at least all those that makes sense) in my own class, by mostly just chaining the call to the underlying HttpListener object. What do you think? Final question: If I go the way of the interface, assuming the interface maps 1-to-1 onto the HttpListener class, and written just to add support for mocking, is such an interface called a wrapper or an adapter?

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  • Grails GORM rarely works in domain classes

    - by Vena
    I have many to many relationship between User and Organization. I want to delete user from all his organizations when the user is being deleted, so this is basically what I came up with: class User { ... def beforeDelete() { def user = User.get(id) Organization.all.each { it.removeFromMembers(user) it.save() } } } This surprisingly doesn't work because User.get(id) returns null even though the user with the given id is in the database, when I look at the log, no sql statement is even executed. So I tried to use load() method insted. ObjectNotFoundException is the result then. So I tried this as I was quite desperate: def user = User.find("from User as u where u.id = ?", [1L]) This, for some reason, works. But now, the line with it.removeFromMembers(user) throws NullPointerException. I tried to put this logic in my UserController and it works! Why is this? Why can't I do this in domain classes? This makes beforeDelete hook (and all the others too) pretty useless.

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  • tiemout for a function that waits indefiinitely (like listen())

    - by Fantastic Fourier
    Hello, I'm not quite sure if it's possible to do what I'm about to ask so I thought I'd ask. I have a multi-threaded program where threads share a memory block to communicate necessary information. One of the information is termination of threads where threads constantly check for this value and when the value is changed, they know it's time for pthread_exit(). One of the threads contains listen() function and it seems to wait indefinitely. This can be problematic if there are nobody who wants to make connection and the thread needs to exit but it can't check the value whether thread needs to terminate or not since it's stuck on listen() and can't move beyond. while(1) { listen(); ... if(value == 1) pthread_exit(NULL); } My logic is something like that if it helps illustrate my point better. What I thought would solve the problem is to allow listen() to wait for a duration of time and if nothing happens, it moves on to next statement. Unfortunately, none of two args of listen() involves time limit. I'm not even sure if I'm going about the right way with multi-threaded programming, I'm not much experienced at all. So is this a good approach? Perhaps there is a better way to go about it? Thanks for any insightful comments.

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  • What, if any, printable character did a user type based on the values in a given System.Windows.Form

    - by Corey Trager
    As a workaround for a problem, I think I have to handle KeyDown events to get the printable character the user actually typed. KeyDown supplies me with a KeyEventArgs object with the properities KeyCode, KeyData, KeyValue, Modifiers, Alt, Shift, Control. My first attempt was just to consider the KeyCode to be the ascii code, but KeyCode on my keyboard is 46, a period ("."), so I end up printing a period when the user types the delete key. So, I know my logic is inadequate. (For those who are curious, the problem is that I have my own combobox in a DataGridView's control collection and somehow SOME characters I type don't produce the KeyPress and TextChanged ComboBox events. These letters include Q, $, %.... This code will reproduce the problem. Generate a Form App and replace the ctor with this code. Run it, and try typing the letter Q into the two comboxes. public partial class Form1 : Form { ComboBox cmbInGrid; ComboBox cmbNotInGrid; DataGridView grid; public Form1() { InitializeComponent(); grid = new DataGridView(); cmbInGrid = new ComboBox(); cmbNotInGrid = new ComboBox(); cmbInGrid.Items.Add("a"); cmbInGrid.Items.Add("b"); cmbNotInGrid.Items.Add("c"); cmbNotInGrid.Items.Add("d"); this.Controls.Add(cmbNotInGrid); this.Controls.Add(grid); grid.Location = new Point(0, 100); this.grid.Controls.Add(cmbInGrid); }

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  • Are there good reasons not to use an ORM?

    - by hangy
    During my apprenticeship, I have used NHibernate for some smaller projects which I mostly coded and designed on my own. Now, before starting some bigger project, the discussion arose how to design data access and whether or not to use an ORM layer. As I am still in my apprenticeship and still consider myself a beginner in enterprise programming, I did not really try to push in my opinion, which is that using an object relational mapper to the database can ease development quite a lot. The other coders in the development team are much more experienced than me, so I think I will just do what they say. :-) However, I do not completely understand two of the main reasons for not using NHibernate or a similar project: One can just build one’s own data access objects with SQL queries and copy those queries out of Microsoft SQL Server Management Studio. Debugging an ORM can be hard. So, of course I could just build my data access layer with a lot of SELECTs etc, but here I miss the advantage of automatic joins, lazy-loading proxy classes and a lower maintenance effort if a table gets a new column or a column gets renamed. (Updating numerous SELECT, INSERT and UPDATE queries vs. updating the mapping config and possibly refactoring the business classes and DTOs.) Also, using NHibernate you can run into unforeseen problems if you do not know the framework very well. That could be, for example, trusting the Table.hbm.xml where you set a string’s length to be automatically validated. However, I can also imagine similar bugs in a “simple” SqlConnection query based data access layer. Finally, are those arguments mentioned above really a good reason not to utilise an ORM for a non-trivial database based enterprise application? Are there probably other arguments they/I might have missed? (I should probably add that I think this is like the first “big” .NET/C# based application which will require teamwork. Good practices, which are seen as pretty normal on Stack Overflow, such as unit testing or continuous integration, are non-existing here up to now.)

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  • How to embed a precharged collection of non-entity forms in symfony2

    - by metalvarez
    I want to embed a collection of precharged non-entity forms, here is the code, first is the parent form buildForm method. public function buildForm(FormBuilderInterface $builder, array $options) { $builder->add("example1")->add("example2"); $builder->addEventListener(FormEvents::PRE_SET_DATA, function (FormEvent $event) { /*some logic to do before adding the collection of forms*/ $form->add('aclAccess', 'collection', array( 'type' => new ChildFormType(), 'allow_add' => true, 'mapped' => false, 'data' => /* I dont know how to precharge a collection of non-entity forms*/ )); }); } now the child form public function buildForm (FormBuilderInterface $builder, array $options) { $builder->add("test1", "text", array("read_only" => true, "data" => "test")); $builder->->add("test2", "choice", array( 'choices' => array('opt1' => 'Opt1', 'opt2' => 'Opt2'), 'multiple' => true, 'expanded' => true )); } so basicly i want to manage those child options in the test2 field as separated forms, each option group will depend on the value of the test1 field, i know this can be done by coding everythin in twig without form classes but i think having form classes its the best practice to run phpunit test, for maintainability, etc ...

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  • Typical SVN repo structure seems to be sub-optimal for continuous integration...

    - by Dave
    I've set up our SVN repository like the Subversion book suggests, and this is also how my previous companies have done it. It looks something like this: /trunk /branches /tags /extlibs /docs where the first three are pretty obvious, and extlibs is for 3rd party assemblies that we wouldn't typically recompile ourselves. All of this works great for the daily development stuff. Now I've installed TeamCity and have builds, unit tests, code coverage, and code analysis running. Everything is great, except for the fact that this code structure results in too much code getting downloaded. So here's the catch 22, in my opinion: it's silly to download all of aforementioned folders from the SVN repo when I only need /trunk and /extlibs. But I can only specify one repo folder to download in the TeamCity VCS settings. So then the other possibility is to put the /extlibs folder into /trunk, but in order to compile branches, /extlibs would have to go into all of those as well (since I usually branch the trunk, and not individual subfolders... and this would seem infinitely more evil since /extlibs could actually be larger than /trunk and /branches, with all of the binaries stored there... Do you guys have any suggestions for me? Thanks!

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  • How to DRY on CRUD parts of my Rails app?

    - by kolrie
    I am writing an app which - similarly to many apps out there - is 90% regular CRUD things and 10% "juice", where we need nasty business logic and more flexibility and customization. Regarding this 90%, I was trying to stick to the DRY principle as much as I can. As long as controllers go, I have found resource_controller to really work, and I could get rid of all the controllers on that area, replacing them with a generic one. Now I'd like to know how to get the same with the views. On this app I have an overall, application.html.erb layout and then I must have another layout layer, common for all CRUD views and finally a "core" part: On index.html.erb all I need to generate a simple table with the fields and labels I indicate. For new and edit, also generic form edition, indicating labels and fields (with a possibility of providing custom fields if needed). I am not sure I will need show, but if I do it would be the same as new and edit. What plugins and tools (or even articles and general pointer) would help me to get that done? Thanks, Felipe.

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  • When are predicates appropriate and what is the best pattern for usage

    - by Maxim Gershkovich
    When are predicates appropriate and what is the best pattern for usage? What are the advantages of predicates? It seems to me like most cases where a predicate can be employed a tight loop would accomplish the same functionality? I don’t see a reusability argument given you will probably only implement a predicate in one method right? They look and feel nice but besides that they seem like you would only employ them when you need a quick hack on the collection classes? UPDATE But why would you be rewriting the tight loop again and again? In my mind/code when it comes to collections I always end up with something like Class Person End Class Class PersonList Inherits List(Of Person) Function FindByName(Name) as Person tight loop.... End Function End Class @Ani By that same logic I could implement the method as such Class PersonList Inherits List(Of Person) Function FindByName(Name) as PersonList End Function Function FindByAge(Age) as PersonList End Function Function FindBySocialSecurityNumber(SocialSecurityNumber) as PersonList End Function End Class And call it as such Dim res as PersonList = MyList.FindByName("Max").FindByAge(25).FindBySocialSecurityNumber(1234) and the result along with the amount of code and its reusability is largely the same, no? I am not arguing just trying to understand.

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  • Mutually beneficial IP/copyright clauses for contract-based freelance work

    - by Nathan de Vries
    I have a copyright section in the contract I give to my clients stating that I retain copyright on any works produced during my work for them as an independent contractor. This is most definitely not intended to place arbitrary restrictions on my clients, but rather to maintain my ability to decide on how the software I create is licensed and distributed. Almost every project I work on results in at least one part of it being released as open source. Every project I work on makes use of third-party software released in the same fashion, so returning the favour is something I would like to continue doing. Unfortunately, the contract is not so clear when it comes to defining the rights of the client in the use of said software. I mention that the code will be licensed to them, but do not mention specifics about exclusivity, ability to produce derivatives etc. As such, a client has raised concerns about the copyright section of my contract, and has suggested that I reword it such that all copyrights are transferred entirely to the client on final payment for the project. This will almost certainly reduce my ability to distribute the software I have created; I would much prefer to find a more mutually beneficial agreement where both our concerns are appeased. Are there any tried and true approaches to licensing software in this kind of situation? To summarise: I want to maintain the ability to license (parts of) the software under my own terms, independently of my relationship with the client; with some guarantee to the client that no trade-secrets or critical business logic will be shared; giving them the ability to re-use my code in their future projects; but not necessarily letting them sell it (I'm not sure about this, though...what happens if they sell their business and the software along with it?) I realise that everyone's feedback is going to be prefixed with "IANAL", however I appreciate any thoughts you might have on the matter.

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  • setup Qt and PyQt on mac osx so my app can also deployable on windows

    - by hk_programmer
    Hi, I've been coding with Python and C++ and now need to work on building a gui for data visualization purposes. I work on Mac Snow Leopard (intel), python 3.1 using gcc 4.2.1 (from Xcode 3.1) I wanted to first install Qt and then PyQt. And my goals are to be able to: - quickly prototype GUI and the accompanied logic that drives the GUI using PyQt and python - if I decided I need the speed, or if it's fairly easy to translate my GUI into C++ using the Qt tools, I have the options to translate my app into C++ - Be able to deploy my application onto Windows (both the python and c++ version of my app) Give the goals above, what are the correct steps I should take and what issues i should be aware of when setting up Qt and PyQt. Which other deployment tools do I need? From my readings so far, here's what I have: download the Qt source for mac and configure it with -platform macx-g++42 -arch x86_64 -no-framework (i've read somewhere that building as framework causes some trouble in deployment and/or debugging, can't find the article anymore) download latest SIP source and build download latest PyQt and build from source (any special options I should pay attention to?) For deployment, I've read that I would need to use py2exe/cx_freeze for windows, p2app for mac: http://arstechnica.com/open-source/guides/2009/03/how-to-deploying-pyqt-applications-on-windows-and-mac-os-x.ars but seems like what the article describe is deploying an app you build on windows on the windows platform and vice versa. How do you deploy to windows (is it even possible?) if you are writing your Qt app on a mac ? Really appreciate the help

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  • How to store a linked list in a struct in C

    - by LuckySlevin
    typedef struct child_list {int count; char vo[100]; child_list*next;} child_list; typedef struct parent_list { char vo[100]; child_list * head; int count; parent_list * next; } parent_list; As you can see there are two structures. child_list is used to create a linked list. And this list will be stored in a linked list of parent list. My problem is to display the child list which in the parent_list. My desire to get while displaying the linked list of parent_list: This lists work with this logic. I already made append and other stuff. For example if i enter ab cd ab ja cd ab Word Count List ab 3 cd->ja cd 2 ab->ab ja 1 cd The problematic part is displaying child_list which is in the parent_list nodes(List column of output). I don't know my question is clear please ask for further info.

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  • Eliminate full table scan due to BETWEEN (and GROUP BY)

    - by Dave Jarvis
    Description According to the explain command, there is a range that is causing a query to perform a full table scan (160k rows). How do I keep the range condition and reduce the scanning? I expect the culprit to be: Y.YEAR BETWEEN 1900 AND 2009 AND Code Here is the code that has the range condition (the STATION_DISTRICT is likely superfluous). SELECT COUNT(1) as MEASUREMENTS, AVG(D.AMOUNT) as AMOUNT, Y.YEAR as YEAR, MAKEDATE(Y.YEAR,1) as AMOUNT_DATE FROM CITY C, STATION S, STATION_DISTRICT SD, YEAR_REF Y FORCE INDEX(YEAR_IDX), MONTH_REF M, DAILY D WHERE -- For a specific city ... -- C.ID = 10663 AND -- Find all the stations within a specific unit radius ... -- 6371.009 * SQRT( POW(RADIANS(C.LATITUDE_DECIMAL - S.LATITUDE_DECIMAL), 2) + (COS(RADIANS(C.LATITUDE_DECIMAL + S.LATITUDE_DECIMAL) / 2) * POW(RADIANS(C.LONGITUDE_DECIMAL - S.LONGITUDE_DECIMAL), 2)) ) <= 50 AND -- Get the station district identification for the matching station. -- S.STATION_DISTRICT_ID = SD.ID AND -- Gather all known years for that station ... -- Y.STATION_DISTRICT_ID = SD.ID AND -- The data before 1900 is shaky; insufficient after 2009. -- Y.YEAR BETWEEN 1900 AND 2009 AND -- Filtered by all known months ... -- M.YEAR_REF_ID = Y.ID AND -- Whittled down by category ... -- M.CATEGORY_ID = '003' AND -- Into the valid daily climate data. -- M.ID = D.MONTH_REF_ID AND D.DAILY_FLAG_ID <> 'M' GROUP BY Y.YEAR Update The SQL is performing a full table scan, which results in MySQL performing a "copy to tmp table", as shown here: +----+-------------+-------+--------+-----------------------------------+--------------+---------+-------------------------------+--------+-------------+ | id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+--------+-----------------------------------+--------------+---------+-------------------------------+--------+-------------+ | 1 | SIMPLE | C | const | PRIMARY | PRIMARY | 4 | const | 1 | | | 1 | SIMPLE | Y | range | YEAR_IDX | YEAR_IDX | 4 | NULL | 160422 | Using where | | 1 | SIMPLE | SD | eq_ref | PRIMARY | PRIMARY | 4 | climate.Y.STATION_DISTRICT_ID | 1 | Using index | | 1 | SIMPLE | S | eq_ref | PRIMARY | PRIMARY | 4 | climate.SD.ID | 1 | Using where | | 1 | SIMPLE | M | ref | PRIMARY,YEAR_REF_IDX,CATEGORY_IDX | YEAR_REF_IDX | 8 | climate.Y.ID | 54 | Using where | | 1 | SIMPLE | D | ref | INDEX | INDEX | 8 | climate.M.ID | 11 | Using where | +----+-------------+-------+--------+-----------------------------------+--------------+---------+-------------------------------+--------+-------------+ Related http://dev.mysql.com/doc/refman/5.0/en/how-to-avoid-table-scan.html http://dev.mysql.com/doc/refman/5.0/en/where-optimizations.html http://stackoverflow.com/questions/557425/optimize-sql-that-uses-between-clause Thank you!

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  • using spring, hibernate and scala, is there a better way to load test data than dbunit?

    - by egervari
    Here are some things I really dislike about dbunit: 1) You cannot specify the exact ordering the inserts because dbunit likes to group your inserts by table name, and not by the order you define them in the XML file. This is a problem when you have records depending on other records in other tables, so you have to disable foreign key constraints during your tests... which actually sucks because these foreign key constraints will get fired in production while your tests won't be aware of them! 2) They seem hellbent on forcing you to use an xml namespace to define your xml... and I honestly can't be bothered to do this. I like the data.xml without any namespace. It works. But they are so hellbent on deprecating it. 3) Creating different xml files is hard on a per test basis, so it actually encourages creating data for your entire app. Unfortunately, this process is a little bloated too once the data grows in size and things get inter tangled. There has got to be a better way to split up your test data into chunks without having to copy/paste a lot of the test data across all of your tests. 4) Keeping track of id references in a big xml file is just impossible. If you have 130 domain classes, it just gets bewildering. This model simply does not scale. Is there something less bloated and better in the Spring/Hibernate space? db unit has worn out its welcome and I'm really looking for something better.

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  • Total Average Week using a Parameter

    - by Jose
    I have a crystal report that shows sales volumes called week to date volume. It shows current week, previous week, and average week. The report prompts for a date parameter and I extract the week number to get current week and previous week volumes. Did it this way because Mngmt wants to be able to run report whenever. My problem is for Average Week I cant figure out how to get the number of weeks to divide by for my average. Report originates from June 1st, 2010. Right now I have: DATEPART("ww", {?date}) - DATEPART("ww", DATE(2010, 6, 1)) This returns 2 right now which is perfect, so i divide my total by 2. This code will work until the end of the year then I'm hooped. Any idea how I can make this a little more dynamic. I was thinking a counter somehow, just can't get the logic down because the date parameter will keep changing, meaning I cant increase my counter by 1 after each week??? Cheers.

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  • Is there a way to load an existing connection string for Linq to SQL from an app.config file?

    - by Brian Surowiec
    I'm running into a really annoying problem with my Linq to SQL project. When I add everything in under the web project everything goes as expected and I can tell it to use my existing connection string stored in the web.config file and the Linq code pulls directly from the ConfigurationManager. This all turns ugly once I move the code into its own project. I’ve created an app.config file, put the connection string in there as it was in the web.config but when I try to add another table in the IDE keeps forcing me to either hardcode the connection string or creates a Settings file and puts it in there, which then adds a new entry into the app.config file with a new name. Is there a way keep my Linq code in its own project yet still refer back to my config file without the IDE continuously hardcoding the connection string or creating the Settings file? I’m converting part of my DAL over to use Linq to SQL so I’d like to use the existing connection string that our old code is using as well as keep the value in a common location, and one spot, instead of in a number of spots. Manually changing the mode to WebSettings instead of AppSettings works untill I try to add a new table, then it goes back to hardcoding the value or recreating the Settings file. I also tried to switch the project type to be a web project and then rename my app.config to web.config and then everything works as I’d like it to. I’m just not sure if there are any downfalls to keeping this as a web project since it really isn't one. The project only contains the Linq to SQL code and an implementation of my repository classes. My project layout looks like this Website -connectionString.config -web.config (refers to connectionString.config) Middle Tier -Business Logic -Repository Interfaces -etc. DAL -Linq to SQL code -Existing SPROC code -connectionString.config (linked from the web poject) -app.config (refers to connectionString.config)

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