Jump to content
  • Advertisement
Sign in to follow this  
Source

Stupid windows... or stupid me?

This topic is 4729 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

Hi Usually this isn't the kind of question i'd ask on here - but I have done my homework on this and its still causing me grief: I have my engine as a static lib, and my game built on top as another project linking to the lib creating the exe. The problem I have is creating the actual window (im using CWindow). Now for the first few months I had no problem whatsoever with creating a window for my app. Then suddenly the window creation routine failed returning ERROR_INVALID_HANDLE - and I mean suddenly without changing any code in that area. Nothing I did would fix the problem, and getting desperate I moved the window creation code into another area of the program - and bingo with no apparent reason it worked fine... for about 2 weeks. Here's the crazy part: I next moved it back to the original section and it worked again. After moving it back and forth over a couple of months it finally stopped working anywhere. Has anyone else come across an issue like this - or is it something obvious? I'd really like to know why this might be happening - or even any of the reasons for CWindow.create() returning ERROR_INVALID_HANDLE (CreateWindow does the same thing). Any help greatly appreciated thanks for reading =)

Share this post


Link to post
Share on other sites
Advertisement
Show us some code - your window creation routine and the code that seems to mess it all up...

Yeah - Windows programming is hell and everyone who can program in Win32 knows it. [rolleyes]

Oxyd

Share this post


Link to post
Share on other sites
Well i've been programming win32 for quite a while now - but this has never happened to me before =(

anyway - for reference:

class registration...

WNDCLASSEX newClass;
newClass.cbSize = sizeof(WNDCLASSEX);
newClass.style = CS_VREDRAW | CS_HREDRAW;
newClass.hCursor = LoadCursor(0,IDC_ARROW);
newClass.hIcon = LoadIcon( app->instance(),MAKEINTRESOURCE(102));
newClass.hIconSm = NULL;
newClass.lpszMenuName = NULL;
char nClassName[128];
strcpy(nClassName,app->name().c_str());
newClass.lpszClassName = nClassName;
newClass.hbrBackground = NULL;
newClass.hInstance = app->instance();
newClass.lpfnWndProc = app->windowMessageHandler();
newClass.cbClsExtra = 0;
newClass.cbWndExtra = 0;

app->_winClass = RegisterClassEx(&newClass);
if (!app->_winClass)
{
fatalError("_registerClass - window-class not registered");
}



and window creation...

_window.Create( (LPCSTR)_winClass, NULL, CRect(0,0,100,100), app->name().c_str() );

if (!_window.m_hWnd)
{
cprintf("%d", (int)GetLastError());
seriousError("createWindow - window creation/attachment failed");
}



Anyway is there any way its something to do with the fact that the window creation is in a seperate linked-library?

Share this post


Link to post
Share on other sites
a) Scope: Well I would think that the data stored in the structure is copied to some internal memory structure within the API after the call to RegisterClassEx() - but I'm not ruling it out. I would think that I would be getting errors constantly if that were the case - and at the moment its functioning perfectly again.

b) Well I would agree except for the fact that right now its working again. I'm sure it'll stop though in a couple of weeks =(

One thing I didn't make clear: The compiled app either works every time without fail, or the window creation function never succeeds. Usually errors due to corrupt/invalid memory are intermittent - this type of error situation is extremely odd.

Please keep your ideas coming though I'll take any input at the moment, thanks =)

Share this post


Link to post
Share on other sites
Quote:
Original post by Source
Well I would think that the data stored in the structure is copied to some internal memory structure within the API after the call to RegisterClassEx()

Sorry, you're right. I checked.

Share this post


Link to post
Share on other sites
Quote:
Original post by Source
Anyway is there any way its something to do with the fact that the window creation is in a seperate linked-library?


Probably not, although maybe if the library is out of date (However I don't think Visual C++ is that stupid). In other words, make[1] sure you have your dependencies set up. Delete the temporary files (.lib,.obj or .a,.o) and rebuild them.

There's nothing wrong with the actual class creation code. Are you sure the function that registers the class is actually called? In any case, try using the class name instead of the ATOM as the first parameter when calling CWindow::Create.

Quote:
Original post by Konfusius
You're passing a member function to the WNDCLASS. I don't believe that's possible.


No he isn't - all we can see from the source is that he's passing app->windowMessageHandler(), which could return any type of function, probably a static member function which is allowed. As he says, it does work some of the time.

Footnotes


[1][lol] har har funny joke.

Share this post


Link to post
Share on other sites
Yer the first thing I did when the problem arose is to do a complete rebuild for all libraries and the main app (and they are in correct dependancy order).

Yes its a static member function:



WNDPROC windowMessageHandler(void) { return (WNDPROC) _processMessage; }

//and...

static LONG CALLBACK _processMessage( HWND,UINT,WPARAM,LPARAM,bool );





Like I said, it works fine for a while, then stops working until I rearrange it, then it works again for a while - until it stops working - then I put it back to the original place and it works again. Very, very odd. Not sure if this one is going to get solved.

Share this post


Link to post
Share on other sites
Sign in to follow this  

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

We are the game development community.

Whether you are an indie, hobbyist, AAA developer, or just trying to learn, GameDev.net is the place for you to learn, share, and connect with the games industry. Learn more About Us or sign up!

Sign me up!