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  • How can I write reusable Javascript?

    - by RenderIn
    I've started to wrap my functions inside of Objects, e.g.: var Search = { carSearch: function(color) { }, peopleSearch: function(name) { }, ... } This helps a lot with readability, but I continue to have issues with reusabilty. To be more specific, the difficulty is in two areas: Receiving parameters. A lot of times I will have a search screen with multiple input fields and a button that calls the javascript search function. I have to either put a bunch of code in the onclick of the button to retrieve and then martial the values from the input fields into the function call, or I have to hardcode the HTML input field names/IDs so that I can subsequently retrieve them with Javascript. The solution I've settled on for this is to pass the field names/IDs into the function, which it then uses to retrieve the values from the input fields. This is simple but really seems improper. Returning values. The effect of most Javascript calls tends to be one in which some visual on the screen changes directly, or as a result of another action performed in the call. Reusability is toast when I put these screen-altering effects at the end of a function. For example, after a search is completed I need to display the results on the screen. How do others handle these issues? Putting my thinking cap on leads me to believe that I need to have an page-specific layer of Javascript between each use in my application and the generic methods I create which are to be used application-wide. Using the previous example, I would have a search button whose onclick calls a myPageSpecificSearchFunction, in which the search field IDs/names are hardcoded, which marshals the parameters and calls the generic search function. The generic function would return data/objects/variables only, and would not directly read from or make any changes to the DOM. The page-specific search function would then receive this data back and alter the DOM appropriately. Am I on the right path or is there a better pattern to handle the reuse of Javascript objects/methods?

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  • YUI: ensuring DOM elements and scripts are ready

    - by dound
    If I put my inline script after the DOM elements it interacts with, should I still use YUI 3's domready event? I haven't noticed any problems, and it seems like I can count on the browser loading the page sequentially. (I already use YUI().use('node', ... to make sure the YUI functions I need have been loaded since the YUI script is a separate file.) Is there a way to speed up the loading of widgets like YUI 2's calendar? I load the appropriate script in <head> element of my page. I use YUI().use('yui2-calendar', ... to make sure the Calendar widget is available. Unfortunately, this causes a short but noticeable delay when I load my page with the calendar. If I omit the YUI().use('yui2-calendar', ... code then it shows up without a noticeable delay - but I guess this could cause the Calendar to not show up at all if the YUI script doesn't load in time? With regards to #2, is it possible to reduce the visual artifact of the calendar not being present and then showing up? I've made it slightly better by specifying a height and width for the parent div so that at least the space is already allocated = minimal shifting around when it does load.

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  • Shell script to emulate warnings-as-errors?

    - by talkaboutquality
    Some compilers let you set warnings as errors, so that you'll never leave any compiler warnings behind, because if you do, the code won't build. This is a Good Thing. Unfortunately, some compilers don't have a flag for warnings-as-errors. I need to write a shell script or wrapper that provides the feature. Presumably it parses the compilation console output and returns failure if there were any compiler warnings (or errors), and success otherwise. "Failure" also means (I think) that object code should not be produced. What's the shortest, simplest UNIX/Linux shell script you can write that meets the explicit requirements above, as well as the following implicit requirements of otherwise behaving just like the compiler: - accepts all flags, options, arguments - supports redirection of stdout and stderr - produces object code and links as directed Key words: elegant, meets all requirements. Extra credit: easy to incorporate into a GNU make file. Thanks for your help. === Clues === This solution to a different problem, using shell functions (?), Append text to stderr redirects in bash, might figure in. Wonder how to invite litb's friend "who knows bash quite well" to address my question? === Answer status === Thanks to Charlie Martin for the short answer, but that, unfortunately, is what I started out with. A while back I used that, released it for office use, and, within a few hours, had its most severe drawback pointed out to me: it will PASS a compilation with no warnings, but only errors. That's really bad because then we're delivering object code that the compiler is sure won't work. The simple solution also doesn't meet the other requirements listed. Thanks to Adam Rosenfield for the shorthand, and Chris Dodd for introducing pipefail to the solution. Chris' answer looks closest, because I think the pipefail should ensure that if compilation actually fails on error, that we'll get failure as we should. Chris, does pipefail work in all shells? And have any ideas on the rest of the implicit requirements listed above?

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  • Bad linking in Qt unit test -- missing the link to the moc file?

    - by dwj
    I'm trying to unit test a class that inherits QObject; the class itself is located up one level in my directory structure. When I build the unit test I get the standard unresolved errors if a class' MOC file cannot be found: test.obj : error LNK2001: unresolved external symbol "public: virtual void * __thiscall UnitToTest::qt_metacast(char const *)" (?qt_metacast@UnitToTest@@UAEPAXPBD@Z) + 2 missing functions The MOC file is created but appears to not be linking. I've been poking around SO, the web, and Qt's docs for quite a while and have hit a wall. How do I get the unit test to include the MOC file in the link? ==== My project file is dead simple: TEMPLATE = app TARGET = test DESTDIR = . CONFIG += qtestlib INCLUDEPATH += . .. DEPENDPATH += . HEADERS += test.h SOURCES += test.cpp ../UnitToTest.cpp stubs.cpp DEFINES += UNIT_TEST My directory structure and files: C:. | UnitToTest.cpp | UnitToTest.h | \---test | test.cpp (Makefiles removed for clarity) | test.h | test.pro | stubs.cpp | +---debug | UnitToTest.obj | test.obj | test.pdb | moc_test.cpp | moc_test.obj | stubs.obj Edit: Additional information The generated Makefile.Debug shows the moc file missing: SOURCES = test.cpp \ ..\test.cpp \ stubs.cpp debug\moc_test.cpp OBJECTS = debug\test.obj \ debug\UnitToTest.obj \ debug\stubs.obj \ debug\moc_test.obj

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  • ffmpeg(libavcodec). memory leaks in avcodec_encode_video

    - by gavlig
    I'm trying to transcode a video with help of libavcodec. On transcoding big video files(hour or more) i get huge memory leaks in avcodec_encode_video. I have tried to debug it, but with different video files different functions produce leaks, i have got a little bit confused about that :). [Here] (http://stackoverflow.com/questions/4201481/ffmpeg-with-qt-memory-leak) is the same issue that i have, but i have no idea how did that person solve it. QtFFmpegwrapper seems to do the same i do(or i missed something). my method is lower. I took care about aFrame and aPacket outside with av_free and av_free_packet. int Videocut::encode( AVStream *anOutputStream, AVFrame *aFrame, AVPacket *aPacket ) { AVCodecContext *outputCodec = anOutputStream->codec; if (!anOutputStream || !aFrame || !aPacket) { return 1; /* NOTREACHED */ } uint8_t * buffer = (uint8_t *)malloc( sizeof(uint8_t) * _DefaultEncodeBufferSize ); if (NULL == buffer) { return 2; /* NOTREACHED */ } int packetSize = avcodec_encode_video( outputCodec, buffer, _DefaultEncodeBufferSize, aFrame ); if (packetSize < 0) { free(buffer); return 1; /* NOTREACHED */ } aPacket->data = buffer; aPacket->size = packetSize; return 0; }

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  • realloc() & ARC

    - by RynoB
    How would I be able to rewrite the the following utility class to get all the class string values for a specific type - using the objective-c runtime functions as shown below? The ARC documentation specifically states that realloc should be avoided and I also get the following compiler error on this this line: classList = realloc(classList, sizeof(Class) * numClasses); "Implicit conversion of a non-Objective-C pointer type 'void *' to '__unsafe_unretained Class *' is disallowed with ARC" The the below code is a reference to the original article which can be found here. + (NSArray *)classStringsForClassesOfType:(Class)filterType { int numClasses = 0, newNumClasses = objc_getClassList(NULL, 0); Class *classList = NULL; while (numClasses < newNumClasses) { numClasses = newNumClasses; classList = realloc(classList, sizeof(Class) * numClasses); newNumClasses = objc_getClassList(classList, numClasses); } NSMutableArray *classesArray = [NSMutableArray array]; for (int i = 0; i < numClasses; i++) { Class superClass = classList[i]; do { superClass = class_getSuperclass(superClass); if (superClass == filterType) { [classesArray addObject:NSStringFromClass(classList[i])]; break; } } while (superClass); } free(classList); return classesArray; } Your help will be much appreciated. Thanks

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  • Checking for Repeated Strings in 2d list

    - by Zach Santiago
    i have a program where i have a list of names and classes. i have the list in alphabetical order. now im trying to check if names repeat, add the classes to one single name. im trying to write some code like go through names if name is already in list, add the class to the one name. so an example would be, instead of having 'Anita ','phys 1443', and 'Anita','IE 3312' i would just have 'Anita','PHYS 1443','IE 3312'. How would i go about doing this in a logival way, WITHOUT using any sort of built in functions? i tried comparing indexe's like if list[i][0] == list[i+1][0], append list[i+1][1] to an emptylist. while that almost worked, it would screw up at some points along the way. here is my attempt size = len(c) i = 0 c = [['Anita', 'PHYS 1443'], ['Anita', 'IE 3312'], ['Beihuang', 'PHYS 1443'], ['Chiao-Lin', 'MATH 1426'], ['Chiao-Lin', 'IE 3312'], ['Christopher', 'CSE 1310'], ['Dylan', 'CSE 1320'], ['Edmund', 'PHYS 1443'], ['Ian', 'IE 3301'], ['Ian', 'CSE 1320'], ['Ian', 'PHYS 1443'], ['Isis', 'PHYS 1443'], ['Jonathan', 'MATH 2325'], ['Krishna', 'MATH 2325'], ['Michael', 'IE 3301'], ['Nang', 'MATH 2325'], ['Ram', 'CSE 1320'], ['Taesu', 'CSE 1320'], ["Tre'Shaun", 'IE 3312'], ["Tre'Shaun", 'MATH 2325'], ["Tre'Shaun", 'CSE 1310']] ## Check if any names repeat d.append(c[0][0]) while i < size - 1 : if c[i][0] == c[i+1][0] : d.append(c[i][1]) d.append(c[i+1][1]) else : d.append(c[i+1][0]) d.append(c[i+1][1]) i = i + 1 print d output was. ['Anita', 'PHYS 1443', 'IE 3312', 'Beihuang', 'PHYS 1443', 'Chiao-Lin', 'MATH 1426', 'MATH 1426', 'IE 3312', 'Christopher', 'CSE 1310', 'Dylan', 'CSE 1320', 'Edmund', 'PHYS 1443', 'Ian', 'IE 3301', 'IE 3301', 'CSE 1320', 'CSE 1320', 'PHYS 1443', 'Isis', 'PHYS 1443', 'Jonathan', 'MATH 2325', 'Krishna', 'MATH 2325', 'Michael', 'IE 3301', 'Nang', 'MATH 2325', 'Ram', 'CSE 1320', 'Taesu', 'CSE 1320', "Tre'Shaun", 'IE 3312', 'IE 3312', 'MATH 2325', 'MATH 2325', 'CSE 1310']

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  • Migrating to web application with AjaxControlToolkit

    - by Chris
    Hi All, We are currently migrating our ASP.NET website to a web application in Visual Studio 2008. Most of the process has been fairly straight forward, but I have hit one block that is driving me a bit nuts. We are using the AjaxControlToolkit for some functionality, specifically an AutoControlExtender. When this is run locally through VS's development server the extender (dropdown) does not render after the service returns the resultset. However if I deploy the migrated solution to our UAT server the extender functions correctly. I have ensured the Ajax Control Toolkit is properly installed locally on my dev machine (and the dll available in the bin directory), and using debugging have ensured the service is called correctly and runs through without error (which it does). The web application was taken from a server running IIS7. Can anyone confirm if Visual Studio 2008 development server requires a different configuration to IIS 7 (as I believe IIS 6 requires a different configuration to IIS 7), and if there is a resource that provides more info? My own searches have turned up very little in this area. On the other hand, if I am looking in the wrong area any other tips would be appreciated. Thanks Chris

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  • Adapting existing HTML/Javascript model to Titanium's latest release (v 0.9)

    - by Alan Neal
    In pre-0.9 versions of Titanium, one could simply specify an .html file (local or remote) in the tiapp.xml file and interact with it in the same manner as one would on a website. As of version 0.9, that is no the longer case. One creates their entire app dynamically. Unfortunately, this broke my previous implementation and, other than an updated Kitchen Sink, much of the new model and API calls are not covered in the documentation (e.g., createLabel). So, my question is this... What are the simplest steps for re-creating the previous effect (knowingly forgoing some of the advantages of the Titanium's latest approach if necessary)? My previous implementation was exactly as it functions on the website. The website has a single index.html file with no content other than links to JavaScript and style files. The document body's onload event called the first JavaScript function (located in the main script) and, from that point forth, the entire content was dynamically created. How can I set up the latest version of Titanium so that I am poised to do the exact same thing? BTW: Whereas I previously had the choice to keep the files local or remote, I don't believe that remote access (e.g., simply using the webView widget to point to the website) is viable. That's because pages displayed via the webView do not have access to most of the API. Since the iPhone and Safari browsers do not support the file input type, the only means for uploading files (something my app requires) is calling Titanium's function. Thanks in advance.

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  • How to create a variadic (with variable length argument list) function wrapper in JavaScript

    - by U-D13
    The intention is to build a wrapper to provide a consistent method of calling native functions with variable arity on various script hosts - so that the script could be executed in a browser as well as in the Windows Script Host or other script engines. I am aware of 3 methods of which each one has its own drawbacks. eval() method: function wrapper () { var str = ''; for (var i=0; i<arguments.lenght; i++) str += (str ?', ':'') + ',arguments['+i+']'; return eval('[native_function] ('+str+')'); } switch() method: function wrapper () { switch (arguments.lenght) { case 0: return [native_function] (arguments[0]); break; case 1: return [native_function] (arguments[0], arguments[1]); break; ... case n: return [native_function] (arguments[0], arguments[1], ... arguments[n]); } } apply() method: function wrapper () { return [native_function].apply([native_function_namespace], arguments); } What's wrong with them you ask? Well, shall we delve into all the reasons why eval() is evil? And also all the string concatenation... Not a solution to be labeled "elegant". One can never know the maximum n and thus how many cases to prepare. This also would strech the script to immense proportions and sin against the holy DRY principle. The script could get executed on older (pre- JavaScript 1.3 / ECMA-262-3) engines that don't support the apply() method. Now the question part: is there any another solution out there?

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  • mtl, transformers, monads-fd, monadLib, and the paradox of choice

    - by yairchu
    Hackage has several packages for monad transformers: mtl: Monad transformer library transformers: Concrete functor and monad transformers monads-fd: Monad classes, using functional dependencies monads-tf: Monad classes, using type families monadLib: A collection of monad transformers. mtl-tf: Monad transformer library using type families mmtl: Modular Monad transformer library mtlx: Monad transformer library with type indexes, providing 'free' copies. compose-trans: Composable monad transformers (and maybe I missed some) Which one shall we use? mtl is the one in the Haskell Platform, but I keep hearing on reddit that it's uncool. But what's bad about choice anyway, isn't it just a good thing? Well, I saw how for example the authors of data-accessor had to make all these to cater to just the popular choices: data-accessor-monadLib library: Accessor functions for monadLib's monads data-accessor-monads-fd library: Use Accessor to access state in monads-fd State monad class data-accessor-monads-tf library: Use Accessor to access state in monads-tf State monad type family data-accessor-mtl library: Use Accessor to access state in mtl State monad class data-accessor-transformers library: Use Accessor to access state in transformers State monad I imagine that if this goes on and for example several competing Arrow packages evolve, we might see something like: spoonklink-arrows-transformers, spoonklink-arrows-monadLib, spoonklink-tfArrows-transformers, spoonklink-tfArrows-monadLib, ... And then I worry that if spoonklink gets forked, Hackage will run out of disk space. :) Questions: Why are there so many monad transformer packages? Why is mtl [considered] uncool? What are the key differences? Most of these seemingly competing packages were written by Andy Gill and are maintained by Ross Paterson. Does this mean that these packages are not competing but rather work together in some way? And do Andy and Ross consider any of their own packages as obsolete? Which one should me and you use?

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  • Python API for VirtualBox

    - by jessica
    I have made a command-line interface for virtualbox such that the virtualbox can be controlled from a remote machine. now I am trying to implement the commmand-line interface using python virtualbox api. For that I have downloaded the pyvb package (python api documentation shows functions that can be used for implementing this under pyvb package). but when I give pyvb.vb.VB.startVM(instance of VB class,pyvb.vm.vbVM) SERVER SIDE CODE IS from pyvb.constants import * from pyvb.vm import * from pyvb.vb import * import xpcom import pyvb import os import socket import threading class ClientThread ( threading.Thread ): # Override Thread's init method to accept the parameters needed: def init ( self, channel, details ): self.channel = channel self.details = details threading.Thread.__init__ ( self ) def run ( self ): print 'Received connection:', self.details [ 0 ] while 1: s= self.channel.recv ( 1024 ) if(s!='end'): if(s=='start'): v=VB() pyvb.vb.VB.startVM(v,pyvb.vm.vbVM) else: self.channel.close() break print 'Closed connection:', self.details [ 0 ] server = socket.socket ( socket.AF_INET, socket.SOCK_STREAM ) server.bind ( ( '127.0.0.1', 2897 ) ) server.listen ( 5 ) while True: channel, details = server.accept() ClientThread ( channel, details ).start() it shows an error Exception in thread Thread-1: Traceback (most recent call last): File "/usr/lib/python2.5/threading.py", line 486, in __bootstrap_inner self.run() File "news.py", line 27, in run pyvb.vb.VB.startVM(v,pyvb.vm.vbVM.getUUID(m)) File "/usr/lib/python2.5/site-packages/pyvb-0.0.2-py2.5.egg/pyvb/vb.py", line 65, in startVM cmd='%s %s'%(VB_COMMAND_STARTVM, vm.getUUID()) AttributeError: 'str' object has no attribute 'getUUID'

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  • How to automatically expand html select element in javascript

    - by xan
    I have a (hidden) html select object in my menu attached to a menu button link, so that clicking the link shows the list so you can pick from it. When you click the button, it calls some javascript to show the <select>. Clicking away from the <select> hides the list. What I really want is to make the <select> appear fully expanded, as if you had clicked on the "down" arrow, but I can't get this working. I've tried lots of different approaches, but can't make any headway. What I'm doing currently is this: <li> <a href="javascript:showlist();"><img src="/images/icons/add.png"/>Add favourite</a> <select id="list" style="display:none; onblur="javascript:cancellist()"> </select> </li> // in code function showlist() { //using prototype not jQuery $('list').show(); // shows the select list $('list').focus(); // sets focus so that when you click away it calles onblur() } I've tried calling $('list').click(). I've tried setting onfocus="this.click()" But in both cases I'm getting Uncaught TypeError: Object # has no method 'click' which is peculiar as link text says that it supports the standard functions. I've tried setting the .size = .length which works, but doesn't have the same appearance (as when you click to open the element, it floats over the rest of the page.) Does anyone have any suggestions?

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  • Can anyone tell me about a jQuery modal dialog box library that doesn't suck

    - by Ritesh M Nayak
    jQuery based modal dialog boxes are great as long as you do as much as the example tells you to. I need a jQuery based modal dialog box library that has to have the following characteristics: It should be fast, something like the add and link dialog on StackOverflow. Most libraries take an eternity to load the dialog with its fancy effects and stuff. I want to call it using a script. Show a hidden div or a span element inline. MOst of the libraries talk filling an anchor with rel, class and href=#hiddenDiv sort of things. I need to be able to what I want without adding unnecessary attributes to my anchor. Something like this function showDialog(values) { processToChangeDom(values); changeDivTobeDisplayed(); modalDialog.show(); } It should reflect changes I make to the DOM in the hidden Div. I used facebox and found out that it makes a copy of the hidden div and changes to the DOM doesn't reflect on the modal window. I need to be able call the close modal div using javascript and also attach beforeOpen and afterClose handlers to the action. Does anyone have any suggestions? I have already tried facebox, simplemodal and a whole range of libraries, most of them don't support one or the other of these functions I described above.

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  • Windows Programming: ID2D1Bitmap Interface - Getting the Bitmap Data

    - by LostInBrackets
    I've been writing my own library of functions to access some of the new Direct2D Windows libraries. In particular, I've been working on the ID2D1Bitmap interface. I wanted to write a function to return a pointer to the start of the bitmap data (for the editing of particular pixels, or custom encoding or whatever else I might wish for in the future). Unfortunately... problem ahead... I can't seem to find a way to get access to the raw pixel data from the ID2D1Bitmap Interface. Does anyone have an idea how to access this? One of my friends suggested drawing the bitmap to a surface and extracting the bitmap data from there. I don't know if this would work. It definitely seems inefficient and I wouldn't know which kind of surface to use. Any help is appreciated. (c++ in particular, but I assume the code won't be tooo different between languages) (I know I could just read in the data direct from the file, but I'm using the WIC decoders which means it could be in any number of indecipherable formats)

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  • C# - Alternative to System.Time.Timer, to call a function at a specific time.

    - by Fábio Antunes
    Hello everybody. I want to call a specific function on my C# application at a specific time. At first i thought about using a Timer (System.Time.Timer), but that soon became impossible to use. Why? Simple. The Timer Class requires a Interval in milliseconds, but considering that i might want the function to be executed, lets says in a week that would mean: 7 Days = 168 hours; 168 Hours = 10,080 minutes; 10,080 Minutes = 6,048,000 seconds; 6,048,000 Seconds = 6,048,000,000 milliseconds; So the Interval would be 6,048,000,000; Now lets remember that the Interval accepted data type is int, and as we know int range goes from -2,147,483,648 to 2,147,483,647. That makes Timer useless in this case once we cannot set a Interval bigger that 2,147,483,647 milliseconds. So i need a solution where i could specify when the function should be called. Something like this: solution.ExecuteAt = "30-04-2010 15:10:00"; solution.Function = "functionName"; solution.Start(); So when the System Time would reach "30-04-2010 15:10:00" the function would be executed in the application. How can this problem be solved? Thanks just by taking the time to read my question. But if you could provide me with some help i would be most grateful. Additional Info: What these functions will do? Getting climate information and based on that info: Starting / Shutting down other Applications (most of them Console Based); Sending custom Commands to those Console Applications; Power down, Rebooting, Sleep, Hibernate the computer; And if possible schedule the BIOS to Power Up the Computer;

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  • OpenGL bitmap text fails after drawing polygon

    - by kaykun
    I'm using Win32 and OpenGL to to draw text onto a window. I'm using the bitmap font method, with wglUseFontBitmaps. Here is my main rendering function: glClear(GL_COLOR_BUFFER_BIT); glPushMatrix(); glColor3f(1.0f, 0.0f, 1.0f); glBegin(GL_QUADS); glVertex2f(0.0f, 0.0f); glVertex2f(128.0f, 0.0f); glVertex2f(128.0f, 128.0f); glVertex2f(0.0f, 128.0f); glEnd(); glPopMatrix(); glPushMatrix(); glColor3f(1.0f, 1.0f, 1.0f); glRasterPos2i(200, 200); glListBase(fontList); glCallLists(5, GL_UNSIGNED_BYTE, "Test."); glPopMatrix(); SwapBuffers(hDC); As you can see it's very simple and the only thing that it's supposed to do is draw a quadrilateral and draw the text "Test.". But the problem is that drawing a polygon seems to mess up any text operations I try to do after it. If I place the text drawing functions before the polygon, both the text and the polygon draw fine. Is there something I'm missing here? Edit: This problem only happens when the window is run in Fullscreen, by ChangeDisplaySettings. Any reason why this would be??

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  • Securely store a password in program code?

    - by Nick
    My application makes use of the RijndaelManaged class to encrypt data. As a part of this encryption, I use a SecureString object loaded with a password which get's get converted to a byte array and loaded into the RajindaelManaged object's Key at runtime. The question I have is the storage of this SecureString. A user entered password can be entered at run-time, and that can be "securely" loaded into a SecureString object, but if no user entered password is given, then I need to default to something. So ultimately the quesiton comes down to: If I have to have some known string or byte array to load into a SecureString object each time my application runs, how do I do that? The "encrypted" data ultimately gets decrypted by another application, so even if no user entered password is specified, I still need the data to be encrypted while it goes from one app to another. This means I can't have the default password be random, because the other app wouldn't be able to properly decrypt it. One possible solution I'm thinking is to create a dll which only spits out a single passphrase, then I use that passphrase and run it through a couple of different hashing/reorganizing functions at runtime before I ultimately feed it into the secureString object. Would this be secure enough?

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  • Beginner problems with references to arrays in python 3.1.1

    - by Protean
    As part of the last assignment in a beginner python programing class, I have been assigned a traveling sales man problem. I settled on a recursive function to find each permutation and the sum of the distances between the destinations, however, I am have a lot of problems with references. Arrays in different instances of the Permute and Main functions of TSP seem to be pointing to the same reference. from math import sqrt class TSP: def __init__(self): self.CartisianCoordinates = [['A',[1,1]], ['B',[2,2]], ['C',[2,1]], ['D',[1,2]], ['E',[3,3]]] self.Array = [] self.Max = 0 self.StoredList = ['',0] def Distance(self, i1, i2): x1 = self.CartisianCoordinates[i1][1][0] y1 = self.CartisianCoordinates[i1][1][1] x2 = self.CartisianCoordinates[i2][1][0] y2 = self.CartisianCoordinates[i2][1][1] return sqrt(pow((x2 - x1), 2) + pow((y2 - y1), 2)) def Evaluate(self): temparray = [] Data = [] for i in range(len(self.CartisianCoordinates)): Data.append([]) for i1 in range(len(self.CartisianCoordinates)): for i2 in range(len(self.CartisianCoordinates)): if i1 != i2: temparray.append(self.Distance(i1, i2)) else: temparray.append('X') Data[i1] = temparray temparray = [] self.Array = Data self.Max = len(Data) def Permute(self,varray,index,vcarry,mcarry): #Problem Class array = varray[:] carry = vcarry[:] for i in range(self.Max): print ('ARRAY:', array) print (index,i,carry,array[index][i]) if array[index][i] != 'X': carry[0] += self.CartisianCoordinates[i][0] carry[1] += array[index][i] if len(carry) != self.Max: temparray = array[:] for j in range(self.Max):temparray[j][i] = 'X' index = i mcarry += self.Permute(temparray,index,carry,mcarry) else: return mcarry print ('pass',mcarry) return mcarry def Main(self): out = [] self.Evaluate() for i in range(self.Max): array = self.Array[:] #array appears to maintain the same reference after each copy, resulting in an incorrect array being passed to Permute after the first iteration. print (self.Array[:]) for j in range(self.Max):array[j][i] = 'X' print('I:', i, array) out.append(self.Permute(array,i,[str(self.CartisianCoordinates[i][0]),0],[])) return out SalesPerson = TSP() print(SalesPerson.Main()) It would be greatly appreciated if you could provide me with help in solving the reference problems I am having. Thank you.

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  • How can I write classes that don't rely on "global" variables?

    - by Joel
    When I took my first programming course in university, we were taught that global variables were evil & should be avoided at all cost (since you can quickly develop confusing and unmaintainable code). The following year, we were taught object oriented programming, and how to create modular code using classes. I find that whenever I work with OOP, I use my classes' private variables as global variables, i.e., they can be (and are) read and modified by any function within the class. This isn't really sitting right with me, as it seems to introduce the same problems global variables had in languages like C. So I guess my question is, how do I stop writing classes with "global" variables? Would it make more sense to pretend I'm writing in a functional language? By this I mean having all functions take parameters & return values instead of directly modifying class variables. If I need to set any fields, I can just take the output of the function and assign it instead of having the function do it directly. This seems like it might make more maintainable code, at least for larger classes. What's common practice? Thanks!

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  • How Can I Generate Equivalent Output Using the CryptoAPI and the .NET Encryption (TripleDESCryptoSer

    - by S. Butts
    I have some C#/.NET code that encrypts and decrypts data using TripleDES encryption. It sticks to the sample code provided at MSDN pretty closely. The encryption piece looks like the following: TripleDESCryptoServiceProvider _desProvider = new TripleDESCryptoServiceProvider(); //bytes for key and initialization vector //keyBytes is 24 bytes of stuff, vectorBytes is 8 bytes of stuff byte[] keyBytes; byte[] vectorBytes; FileStream fStream = File.Open(locationOfFile, FileMode.Create, FileAccess.Write); CryptoStream cStream = new CryptoStream(fStream, _desProvider.CreateEncryptor(keyBytes, vectorBytes), CryptoStreamMode.Write); BinaryWriter bWriter = new BinaryWriter(cStream); //write out encrypted data //raw data is a few bytes of binary information byte[] rawData; bWriter.Write(rawData); With encrypting and decrypting in C#, this all works like a charm. The problem is I need to write a small Win32 utility that will duplicate the encryption above. I have tried several methods using the CryptoAPI, and I simply do not get output that the .NET piece can decrypt, no matter what I do. Can someone please tell me what the equivalent C++ code is that will produce the same output? I am not certain just what methods of the CryptoAPI the .NET functions use to encrypt the data. What options are used, and what method of generating the key is used? Before someone suggests that I just write it in C# anyway, or create some common library bridge for them, those options are unfortunately off the table. It really has to work in Win32 with .NET and without using a DLL. I have some leeway in changing the C# code. I apologize in advance if this is bone-headed, as I am new to encryption.

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  • Find the flaws in the concept...

    - by Trindaz
    A web based web browser. Sounds silly right? Here's a use case. All comments about what could go wrong, and if anyone has tried and failed at this, very much wanted User goes to www.theBrowser.com and logs in with credentials specific to theBrowser.com. User tells theBrowser what their username and password for various sites are User goes to theBrowser.com/?uri=somesite.com theBrowser sends off the http request with User's log in details, then sends the http response back to User. This lets theBrowser do weird and wonderful functions like change colours / style sheets / etc. to every site that gets passed through it. From a technical stand point, storing username and password and passing them along is not a challenge for one user, but if there were a few, I'd have to use some kind of server based browser software to store a session per user logged in at theBrowser.com. How could I do that? Will I have to start from scratch? Obviously privacy and security are issues. Would theBrowser.com be too great a risk, even if users are fully warned? Cheers, Dave

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  • Race condition during thread start?

    - by user296353
    Hi, I'm running the following code to start my threads, but they don't start as intended. For some reason, some of the threads start with the same objects (and some don't even start). If I try to debug, they start just fine (extra delay added by me clicking F10 to step through the code). These are the functions in my forms app: private void startWorkerThreads() { int numThreads = config.getAllItems().Count; int i = 0; foreach (ConfigurationItem tmpItem in config.getAllItems()) { i++; var t = new Thread(() => WorkerThread(tmpItem, i)); t.Start(); //return t; } } private void WorkerThread(ConfigurationItem cfgItem, int mul) { for (int i = 0; i < 100; i++) { Thread.Sleep(10*mul); } this.Invoke((ThreadStart)delegate() { this.textBox1.Text += "Thread " + cfgItem.name + " Complete!\r\n"; this.textBox1.SelectionStart = textBox1.Text.Length; this.textBox1.ScrollToCaret(); }); } Anyone able to help me out? Cheers!

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  • Alternative to jQuery's .toggle() method that supports eventData?

    - by Bungle
    The jQuery documentation for the .toggle() method states: The .toggle() method is provided for convenience. It is relatively straightforward to implement the same behavior by hand, and this can be necessary if the assumptions built into .toggle() prove limiting. The assumptions built into .toggle have proven limiting for my current task, but the documentation doesn't elaborate on how to implement the same behavior. I need to pass eventData to the handler functions provided to toggle(), but it appears that only .bind() will support this, not .toggle(). My first inclination is to use a flag global to a single handler function to store the click state. In other words, rather than: $('a').toggle(function() { alert('odd number of clicks'); }, function() { alert('even number of clicks'); }); do this: var clicks = true; $('a').click(function() { if (clicks) { alert('odd number of clicks'); clicks = false; } else { alert('even number of clicks'); clicks = true; } }); I haven't tested the latter, but I suspect it would work. Is this the best way to do something like this, or is there a better way that I'm missing? Thanks!

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  • Quadratic Bezier Curve: Calculate Tangent

    - by stefan.at.wpf
    I have a quadratic bezier curve and I want to calculate the slope of the tangent in a given point. For example, let it be the middlepoint of the quadratic bezier curve, therefore t=0.5 (please see the link below for a picture of this). I've calculated the first derivative of the formula for the quadratic bezier curve; however I get 400 as value for the slope, though it should be 0. Maybe I'm using the first derivative in a wrong way? I know I could also calculate the tangents using trigonometric functions; however I'd like to do it using the first derivative, shouldn't this be possible? Thanks for any hint! For clarification / please note: I'm interested in a general way to get the slope in a arbitrary given point on a quadratic bezier curve, not only to get the tangent in the start- and end point. A picture of my problem including the text above: http://cid-0432ee4cfe9c26a0.skydrive.live.com/self.aspx/%c3%96ffentlich/Quadratic%20Bezier%20Curve.pdf Thank you very much for any hint!

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