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  • NavBar displaying back twice when app changed to landscape mode

    - by Graeme
    Hi, Not sure what's going on here, but my iPhone apps nav bar shows back and the title of my detail view controller even when I'm back to the original view. It wasn't happening earlier, it has changed recently (but not sure when exactly). E.g. I click on a row, view the didSelectRow XIB and then click back on the NavBar controller, but it still shows back even though the view does change back to the original table view. I then have to press back again and then it clears. Update: It's as if its trying to go back three times instead of two. Because, if you visit another row without removing the back button, it stores it as if you need to go back twice. It works fine in portrait mode. Any ideas?

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  • stripe payment issue ruby on rails

    - by Admir Huric
    So I have made a stripe payment option in my app. When I click the button pay now, it shows me that the payment is successful. and when I go to my stripe account and go to stripe-test and check logs, I can see my test payment with the code 200 OK. But this payment doesn't show in stripe-test events, or in stripe-test payments. Are the payments from logs processed the next day or am I doing something wrong? def charge Stripe.api_key = "some_test_api_key" customer = Stripe::Customer.retrieve(stripe_customer_id) if stripe_customer_id.nil? Stripe::Charge.create( :amount => 2500, :currency => "cad", :customer => stripe_customer_id, :description => "Usage charges for #{name}" ) end rescue Stripe::StripeError => e logger.error "Stripe Error: " + e.message errors.add :base, "Unable to process charge. #{e.message}." false end

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  • How are you using C++0x today? [closed]

    - by Roger Pate
    This is a question in two parts, the first is the most important and concerns now: Are you following the design and evolution of C++0x? What blogs, newsgroups, committee papers, and other resources do you follow? Even where you're not using any new features, how have they affected your current choices? What new features are you using now, either in production or otherwise? The second part is a follow-up, concerning the new standard once it is final: Do you expect to use it immediately? What are you doing to prepare for C++0x, other than as listed for the previous questions? Obviously, compiler support must be there, but there's still co-workers, ancillary tools, and other factors to consider. What will most affect your adoption? Edit: The original really was too argumentative; however, I'm still interested in the underlying question, so I've tried to clean it up and hopefully make it acceptable. This seems a much better avenue than duplicating—even though some answers responded to the argumentative tone, they still apply to the extent that they addressed the questions, and all answers are community property to be cleaned up as appropriate, too.

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  • Can Windows Mobile Synch Services use a business layer

    - by Andy Kakembo
    We're building a Win Mobile 6 warehouse app which needs to update our server based corporate DB. We've got a C# business layer that sits on our app server and we'd really like our warehouse app to go through this. We also like MS Synch Services. Is there a way to combine the two ie can we use sync services but get them to go through our business layer ? Has anyone done this and got an example I can follow ? Is there a best practice for this kind of scenario ? Thanks, Andy

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  • How can I create a Base64-Encoded string from an GDI+ Image in C++?

    - by Schnapple
    I asked a question recently, How can I create an Image in GDI+ from a Base64-Encoded string in C++?, which got a response that led me to the answer. Now I need to do the opposite - I have an Image in GDI+ whose image data I need to turn into a Base64-Encoded string. Due to its nature, it's not straightforward. The crux of the issue is that an Image in GDI+ can save out its data to either a file or an IStream*. I don't want to save to a file, so I need to use the resulting stream. Problem is, this is where my knowledge breaks down. This first part is what I figured out in the other question // Initialize GDI+. GdiplusStartupInput gdiplusStartupInput; ULONG_PTR gdiplusToken; GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL); // I have this decode function from elsewhere std::string decodedImage = base64_decode(Base64EncodedImage); // Allocate the space for the stream DWORD imageSize = decodedImage.length(); HGLOBAL hMem = ::GlobalAlloc(GMEM_MOVEABLE, imageSize); LPVOID pImage = ::GlobalLock(hMem); memcpy(pImage, decodedImage.c_str(), imageSize); // Create the stream IStream* pStream = NULL; ::CreateStreamOnHGlobal(hMem, FALSE, &pStream); // Create the image from the stream Image image(pStream); // Cleanup pStream->Release(); GlobalUnlock(hMem); GlobalFree(hMem); (Base64 code) And now I'm going to perform an operation on the resulting image, in this case rotating it, and now I want the Base64-equivalent string when I'm done. // Perform operation (rotate) image.RotateFlip(Gdiplus::Rotate180FlipNone); IStream* oStream = NULL; CLSID tiffClsid; GetEncoderClsid(L"image/tiff", &tiffClsid); // Function defined elsewhere image.Save(oStream, &tiffClsid); // And here's where I'm stumped. (GetEncoderClsid) So what I wind up with at the end is an IStream* object. But here's where both my knowledge and Google break down for me. IStream shouldn't be an object itself, it's an interface for other types of streams. I'd go down the road from getting string-Image in reverse, but I don't know how to determine the size of the stream, which appears to be key to that route. How can I go from an IStream* to a string (which I will then Base64-Encode)? Or is there a much better way to go from a GDI+ Image to a string?

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  • Java - Problem in deploying Web Application

    - by Yatendra Goel
    I have built a Java Web Application and packed it in a .war file and tested it on my local tomcat server and it is running fine. But when I deployed it on my client's server, it is showing an error. According to the remote server (my client's server), it is not finding a tld file packed in a jar file which I had placed in WEB-INF/lib directory. But when I checked the WEB-INF/lib directory for the jar file, i found that it was there. The contents of META-INF/MANIFEST.MF is as follows: Manifest-Version: 1.0 Class-Path: I think that there is no need to explicitly mention the classpath of WEB-INF/lib directory as it is in the classpath of any web application by default. Then, why the server can't find the jar file in the lib directory when I deployed it on a remote server and why it is working when I deployed the same application on my local server. I posted a question for this at http://stackoverflow.com/questions/2441254/struts-1-struts-taglib-jar-is-not-being-found-by-my-web-application but found that the problem is unusual as nobody could answer it. So my questions are as follows: Q1. Is WEB-INF/lib still remains on the classpath if I leave the classpath entry blank as shown above in the MANIFEST.MF file or I should delete the classpath entry completely from the file or I should explicitly enter Class-Path: /WEB-INF/lib as the classpath entry? Q2. I have JSP pages, Servlets and some helper classes in the web application. Jsp pages are located at the root. Servlets and helper classes are located in WEB-INF/classes folder. So Is there any problem if my helper classes are located in the WEB-INF/classes folder? Note: Please note that this question is not same as my previous question. It is a follow-up question of my previous question. Both the servers (local and remote) are tomcat servers.

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  • php push 2d array into mysql

    - by john
    Hay All, I cant seem to get my head around this dispite the number to examples i read. Basically I have a 2d array and want to insert it into MySQL. The array contains a few strings. I cant get the following to work... $value = addslashes(serialize($temp3));//temp3 is my 2d array, do i need to use keys? (i am not at the moment) $query = "INSERT INTO table sip (id,keyword,data,flags) VALUES(\"$value\")"; mysql_query($query) or die("Failed Query"); Thanks Guys,

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  • Fluxbox compiling problems after making a change.

    - by Jack
    I'm trying to make the change here: http://fluxbox-wiki.org/index.php?title=Howto_Make_dblclick_titlebar_maximize I am using the current git version of the fluxbox source. I assume that those instructions are perhaps no longer valid for the current git version. In the void FluxboxWindow::setupWindow() function I can see no references to CommandRef or frame. I would like to know if it is possible that I could work out where they should go in that function, with only having a limited knowledge? I am still trying to learn programming and don't know enough just yet to work out where they should go. I assume I can't just paste in the suggested lines anywhere in that function, but why not? I can paste the source if needed, but I am unsure where to paste to.

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  • What do we log and why do we log it?

    - by Lucas
    This has been bugging me for quite some time. Reading various questions on SO, blogs and listening to colleagues, I keep hearing how important "logging" is. How various logging frameworks stack up against each other, and how there are so many to pick from it's (apparently) ridiculous. Now, I know what logging is. What I don't know is what is supposed to be logged and why. Sure, I can guess. Exceptions? Sounds like something one might want to log... but which exceptions? And is it only exceptions? And what do I do with the logged information? If it's an in-house app, then that could probably be put to good use, but if it's a commercial desktop application, how is the log of... whatever... helping anyone? I doubt regular users would be peeking inside. Is it then something you ask the users to provide on request? I'm deeply frustrated by my own ignorance in this. It's also surprising how little information there is about this. The info on the websites of the various logging frameworks is all written for an audience that already knows what it wants to log, and knows why it needs to do so. Same things goes for the various discussions on SO about logging, like for instance this highly voted up question on Logging best practices. For a question with so many votes, it's almost comical how there's next to nothing in there that would answer my what and why questions. So being finally fed up, I'm asking here: what do people log, and why do they log it?

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  • Javascript JQUERY AJAX: When Are These Implemented

    - by Michael Moreno
    I'm learning javascript. Poked around this excellent site to gather intel. Keep coming across questions / answers about javascript, JQUERY, JQUERY with AJAX, javascript with JQUERY, AJAX alone. My conclusion: these are all individually powerful and useful. My confusion: how does one determine which/which combination to use ? I've concluded that javascript is readily available on most browsers. For example, I can extend a simple HTML page with <html> <body> <script type="text/javascript"> document.write("Hello World!"); </script> </body> </html> However, within the scope of Python/DJANGO, many of these questions are JQUERY and AJAX related. At which point or under what development circumstances would I conclude that javascript alone isn't going to "cut it", and I need to implement JQUERY and/or AJAX and/or some other permutation ?

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  • How to Connect to a Mysql database using PHP?

    - by Karthik
    <?php mysql_connect("localhost", "username", "password") or die(mysql_error()); echo "Connected to MySQL<br />"; ?> This is the code I am using to check if I am able to connect to Mysql. I am having problem connecting using this code. Should I change localhost to the name of the website? I tried ("www.abc.com","login username", "password") even this is not working.

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  • Anchoring the Action URL of a Form

    - by John
    Hello, I am using a function that leads users to a file called "comments2.php": <form action="http://www...com/.../comments/comments2.php" method="post"> On comments2.php, data passed over from the form is inserted into MySQL: $query = sprintf("INSERT INTO comment VALUES (NULL, %d, %d, '%s', NULL)", $uid, $subid, $comment); mysql_query($query) or die(mysql_error()); Then, later in comments2.php, I am using a query that loops through entries meeting certain criteria. The loop contains a row with the following information: echo '<td rowspan="3" class="commentname1" id="comment-' . $row["commentid"] . '">'.stripslashes($row["comment"]).'</td>'; For the function above, I would like the URL to be anchored by the highest value of "commentid" for id="comment-' . $row["commentid"] . '" How can this be done? Thanks in advance, John

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  • MovieClip property - what is the url it goes when I click on it.

    - by cosmorocket
    I have bought a flash template in an online store. There are different buttons on it and some of them link to existing local html files from the pack - index-1.html, index-2.html etc. There are also some buttons that don't go anywhere right now but they are intended to be linked to some urls too. They react with animation on mouse rollover and I suppose they should go to some url if I set it somewhere on click. But there is no documentation about that in the pack. I searched through the Flash source file and all html pages files for something like "index", "geturl", also looked through them manually to realize how it could be made but with no luck. So, my question - is that possible that way or another to make that MovieClip button link to some my page, for example, "contacts.html". Thanks.

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  • rendering front-end of survey into an MVC app

    - by HotKey
    Lately I have been watching Pluralsight intro videos on MVC 3. I have never worked with the Model View Control approach before, but I'm starting to understand how these 3 crucial parts of an app are separated. I created a front-end prototype of a survey I would like to implement into a View of my MVC web app. The survey is in HTML, CSS, using jQuery to deliver content changes depending on the type of evaluation (6-11 questions), and jQuery UI for a couple slider ratings. I noticed through tutorials that you can use an HTML form and helpers that allow the user to edit content, but my prototype already allows the users to rate via radio buttons, comment text boxes, and sliders. Would I need to change any of my existing code if I just want to store this employee data to the Model, and depending on what survey's the employee has completed through the Controller, disable drop down fields? Also, would I store the current employee data on submit of survey through an HttpPost in the Controller to the Model? My apologies if my questions seem rather vague. Could someone point me in the right direction to a resource or documentation similar to my needs above? The Pluralsight videos are taking me in the wrong direction.

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  • How to deal with clients and iterations in Agile team?

    - by Ondrej Slinták
    This thread is a follow up to my previous one. It's in fact 2 questions, so I hope no one minds, as they are dependent on each other. We are starting a new project at work and we consider it as a great opportunity to try Agile techniques in action. We had a brainstorming about ideas we read in several books and articles, and came up with concept that would suit us the best: 2 weeks iteration, followed by call with clients who would choose what stuff they want to have in next iteration. I just have few more questions, which we couldn't figure out ourselves. What to do in the first iteration? What to, generally, do in the first few iterations if we start from the scratch? Just give it a month of development to code core of the application or start with simple wire-frames with limited pre-coded functionality? What usually clients want to see? Shiny stuff that doesn't work or ugly stuff that does work? How to communicate with clients? Our initial thought it to set the process to something like this: Is it a good idea to have a Focal Point on client side or is it better to communicate straight with all the clients to prevent miscommunication? Any thoughts are welcome! Thanks in advance.

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  • G++ Multi-platform memory leak detection tool

    - by indyK1ng
    Does anyone know where I can find a memory memory leak detection tool for C++ which can be either run in a command line or as an Eclipse plug-in in Windows and Linux. I would like it to be easy to use. Preferably one that doesn't overwrite new(), delete(), malloc() or free(). Something like GDB if its gonna be in the command line, but I don't remember that being used for detecting memory leaks. If there is a unit testing framework which does this automatically, that would be great. This question is similar to other questions (such as http://stackoverflow.com/questions/283726/memory-leak-detection-under-windows-for-gnu-c-c ) however I feel it is different because those ask for windows specific solutions or have solutions which I would rather avoid. I feel I am looking for something a bit more specific here. Suggestions don't have to fulfill all requirements, but as many as possible would be nice. Thanks. EDIT: Since this has come up, by "overwrite" I mean anything which requires me to #include a library or which otherwise changes how C++ compiles my code, if it does this at run time so that running the code in a different environment won't affect anything that would be great. Also, unfortunately, I don't have a Mac, so any suggestions for that are unhelpful, but thank you for trying. My desktop runs Windows (I have Linux installed but my dual monitors don't work with it) and I'd rather not run Linux in a VM, although that is certainly an option. My laptop runs Linux, so I can use that tool on there, although I would definitely prefer sticking to my desktop as the screen space is excellent for keeping all of the design documentation and requirements in view without having to move too much around on the desktop. NOTE: While I may try answers, I won't mark one as accepted until I have tried the suggestion and it is satisfactory. EDIT2: I'm not worried about the cross-platform compatibility of my code, it's a command line application using just the C++ libraries.

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  • Can't Insert Data Into Tables Containing Auto Increment Primary Key Using PHP Prepared Statements

    - by Drew
    I know I have that my connection to the database works, and a test I did using no auto-increment id worked fine for me. The code below refuses to work and I can't find a a way around it. My table has 3 columns, ID (auto increment), name and value. What do I need to change in order to get this to work? Thanks in advance //create placeholder query $query = "INSERT INTO prepared_test (name, value) VALUES (?,?)"; //prepare the query $stmt = mysqli_prepare($connection, $query); $name = 'steve'; $value = 45; mysqli_bind_param($stmt, array(MYSQLI_BIND_STRING, MYSQLI_BIND_INT), $name, $value); mysqli_execute($stmt); if(mysqli_stmt_affected_rows($stmt) != 1) die("issues"); mysqli_stmt_close($stmt); $connection-close();

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  • how to use a class method as a WIN32 application callback method (WINPROC)... Error static struct HI

    - by numerical25
    I am receiving errors and at the same time trying to make this work so please read what I got to say. Thanks.... I am creating a c++ application and majority of the application is encapsulated into a class. That means that my WinProc function is a static class method that I use as my call back method for my win32 application. The problem is that since I created that as a win32 application, every class member I use inside that method has to be static as well. Including my HINSTANCE class which I use inside of it. Now I receive this error error LNK2001: unresolved external symbol "public: static struct HINSTANCE__ I need to figure out how to make this all work and below is my class declaration. My static member static HINSTANCE m_hInst is causing the error I believe. #pragma once #include "stdafx.h" #include "resource.h" #define MAX_LOADSTRING 100 class RenderEngine { protected: int m_width; int m_height; ATOM RegisterEngineClass(); public: static HINSTANCE m_hInst; //<------ This is causing the error HWND m_hWnd; int m_nCmdShow; TCHAR m_szTitle[MAX_LOADSTRING]; // The title bar text TCHAR m_szWindowClass[MAX_LOADSTRING]; // the main window class name bool InitWindow(); bool InitDirectX(); bool InitInstance(); //static functions static LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam); static INT_PTR CALLBACK About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam); int Run(); }; Below is the implementation #include "stdafx.h" #include "RenderEngine.h" bool RenderEngine::InitWindow() { RenderEngine::m_hInst = NULL; // Initialize global strings LoadString(m_hInst, IDS_APP_TITLE, m_szTitle, MAX_LOADSTRING); LoadString(m_hInst, IDC_RENDERENGINE, m_szWindowClass, MAX_LOADSTRING); if(!RegisterEngineClass()) { return false; } if(!InitInstance()) { return false; } return true; } ATOM RenderEngine::RegisterEngineClass() { WNDCLASSEX wcex; wcex.cbSize = sizeof(WNDCLASSEX); wcex.style = CS_HREDRAW | CS_VREDRAW; wcex.lpfnWndProc = RenderEngine::WndProc; wcex.cbClsExtra = 0; wcex.cbWndExtra = 0; wcex.hInstance = m_hInst; wcex.hIcon = LoadIcon(m_hInst, MAKEINTRESOURCE(IDI_RENDERENGINE)); wcex.hCursor = LoadCursor(NULL, IDC_ARROW); wcex.hbrBackground = (HBRUSH)(COLOR_WINDOW+1); wcex.lpszMenuName = MAKEINTRESOURCE(IDC_RENDERENGINE); wcex.lpszClassName = m_szWindowClass; wcex.hIconSm = LoadIcon(wcex.hInstance, MAKEINTRESOURCE(IDI_SMALL)); return RegisterClassEx(&wcex); } LRESULT CALLBACK RenderEngine::WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) { int wmId, wmEvent; PAINTSTRUCT ps; HDC hdc; switch (message) { case WM_COMMAND: wmId = LOWORD(wParam); wmEvent = HIWORD(wParam); // Parse the menu selections: switch (wmId) { case IDM_ABOUT: DialogBox(m_hInst, MAKEINTRESOURCE(IDD_ABOUTBOX), hWnd, About); break; case IDM_EXIT: DestroyWindow(hWnd); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } break; case WM_PAINT: hdc = BeginPaint(hWnd, &ps); // TODO: Add any drawing code here... EndPaint(hWnd, &ps); break; case WM_DESTROY: PostQuitMessage(0); break; default: return DefWindowProc(hWnd, message, wParam, lParam); } return 0; } bool RenderEngine::InitInstance() { m_hWnd = NULL; m_hWnd = CreateWindow(m_szWindowClass, m_szTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, m_hInst, NULL); if (!m_hWnd) { return FALSE; } if(!ShowWindow(m_hWnd, m_nCmdShow)) { return false; } UpdateWindow(m_hWnd); return true; } // Message handler for about box. INT_PTR CALLBACK RenderEngine::About(HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam) { UNREFERENCED_PARAMETER(lParam); switch (message) { case WM_INITDIALOG: return (INT_PTR)TRUE; case WM_COMMAND: if (LOWORD(wParam) == IDOK || LOWORD(wParam) == IDCANCEL) { EndDialog(hDlg, LOWORD(wParam)); return (INT_PTR)TRUE; } break; } return (INT_PTR)FALSE; } int RenderEngine::Run() { MSG msg; HACCEL hAccelTable; hAccelTable = LoadAccelerators(m_hInst, MAKEINTRESOURCE(IDC_RENDERENGINE)); // Main message loop: while (GetMessage(&msg, NULL, 0, 0)) { if (!TranslateAccelerator(msg.hwnd, hAccelTable, &msg)) { TranslateMessage(&msg); DispatchMessage(&msg); } } return (int) msg.wParam; } and below is the code being used within the WinMain RenderEngine go; int APIENTRY _tWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { UNREFERENCED_PARAMETER(hPrevInstance); UNREFERENCED_PARAMETER(lpCmdLine); // TODO: Place code here. RenderEngine::m_hInst = hInstance; go.m_nCmdShow = nCmdShow; if(!go.InitWindow()) { return 0; } go.Run(); return 0; } If anything does not make any sense, then I apologize, I am a newb. Thanks for the help!!

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  • function and class to show image not working in php

    - by Gully
    i am trying to get get the following working nothing is happen when i use the function i am trying to get it to display images class ItemRes { //items DB var $img=""; } function ShowItemImage($index,$res_a){ if(sizeof($res_a) > $index){ if($res_a[$index] != NULL) { $cimg = $res_a[$index]->img; return "<img src='$cimg' width='70' height='70' style='cursor:pointer'></img>"; } }else{ return "<center class='whitetxt'><strong>Empty</strong></center>"; } } $res_array = array(); $idx=0; $result21 = mysql_query("SELECT * FROM photos WHERE eid='$eid' ORDER BY id DESC") or die (mysql_error()); while ($row21 = mysql_fetch_array($result21)) { $img_path = $row21['path']; $obj = new ItemRes(); $obj->img = $img_path; $res_array[$idx] = $obj; $idx++; } ShowItemImage(0,$res_array) ShowItemImage(1,$res_array)

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  • paged list with checkboxes, keep the checkbox value browsing through the paging?

    - by Dejan.S
    Hi. I got a list of customers I thought I would list in a gridview or a repeater with customer html, it gone have paging. I'm gone have a checkbox for each customer in the list. Do you guys have any suggestions on how I should do to keep the checkbox value when I go to page 2-3-4 ect in the paging. I'm thinking a session to store the id of the checked customers. After I'm done setting the values they go to the database. Do you got any other ideas then the session I'm thinking of? thanks guys

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  • Eclipse debugging "source not found"

    - by James
    I just started using Eclipse so go easy on me ;). But when trying to debug a JUnit test case I get a dialog that states the the source is not found when I get to this line in the code in my test method: Assert.assertEquals(1, contents.size()); I know I should probably go and try and download the source from somewhere, but I really don't want to because I have no interest in stepping into the JUnit code. I have the JUnit runtime jar so Why does Eclipse expect me to have all the referenced tools source code in order to debug my own code (seems somewhat silly)? My main question is though, how can I tell Eclipse to skip this dialog when the source is not available and allow me to continue to debug my own code? [Edit] I've isolated the cause of this. It seems that Eclipse seems to think it needs the source when an exception is thrown by the internal JUnit code. In general is there anyway to tell it that it doesn't and just have it throw up an error dialog of some kind instead?

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  • iphone sdk: Table view not working in the first 5 tabs but in the more view

    - by LHT
    Hi, I only started with sdk but this problem is bugging me now for a view days: I created a UITableView and added it to my Tabs. When this TableView is in the first 4 Tabs and u go look at it, it only shows the items on the table but when clicking on them nothing happens (it doesn't go to the next view). BUT when i put this same tab behind the 5th so it goes in the automatic MORE view everything works fine. I'm assuming this is because this more view is implementing some kind of table class. But i can't figure it out. I compared all the files with a working example but it seems to be all the same. ah ya my current project is a window based application. Though i copied most of the code from a navigation based application. Any ideas?

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  • floating point equality in Python and in general

    - by eric.frederich
    I have a piece of code that behaves differently depending on whether I go through a dictionary to get conversion factors or whether I use them directly. The following piece of code will print 1.0 == 1.0 -> False But if you replace factors[units_from] with 10.0 and factors[units_to ] with 1.0 / 2.54 it will print 1.0 == 1.0 -> True #!/usr/bin/env python base = 'cm' factors = { 'cm' : 1.0, 'mm' : 10.0, 'm' : 0.01, 'km' : 1.0e-5, 'in' : 1.0 / 2.54, 'ft' : 1.0 / 2.54 / 12.0, 'yd' : 1.0 / 2.54 / 12.0 / 3.0, 'mile' : 1.0 / 2.54 / 12.0 / 5280, 'lightyear' : 1.0 / 2.54 / 12.0 / 5280 / 5.87849981e12, } # convert 25.4 mm to inches val = 25.4 units_from = 'mm' units_to = 'in' base_value = val / factors[units_from] ret = base_value * factors[units_to ] print ret, '==', 1.0, '->', ret == 1.0 Let me first say that I am pretty sure what is going on here. I have seen it before in C, just never in Python but since Python in implemented in C we're seeing it. I know that floating point numbers will change values going from a CPU register to cache and back. I know that comparing what should be two equal variables will return false if one of them was paged out while the other stayed resident in a register. Questions What is the best way to avoid problems like this?... In Python or in general. Am I doing something completely wrong? Side Note This is obviously part of a stripped down example but what I'm trying to do is come with with classes of length, volume, etc that can compare against other objects of the same class but with different units. Rhetorical Questions If this is a potentially dangerous problem since it makes programs behave in an undetermanistic matter, should compilers warn or error when they detect that you're checking equality of floats Should compilers support an option to replace all float equality checks with a 'close enough' function? Do compilers already do this and I just can't find the information.

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  • 396 desktop Python apps [closed]

    - by Delirium tremens
    http://sourceforge.net/develop/ - Project Finder - Programming Language - Python ( * 16596 * ) - even so, All Anys - Go - Programming Language - Python ( * 11847 * ) - Desktop ( * 572 * ) - All Desktop Categories (7 + 1 + 67 + 35 + 286 = * 396 * )

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