Add a bitmap to a button

[Pierrot_Dev]

I have compiled the sample code "EmptyPanel" of the sdk, then made my own version with a control bar and some buttons.

I would like to add bitmaps to the buttons, adding the BS_BITMAP style to the native windows buttons then sending

hInst = (HINSTANCE)GetWindowLongPtr((HWND)ctrlBarPlatformWindow, GWLP_HINSTANCE);

hBmp = LoadBitmap(hInst, MAKEINTRESOURCE(IDB_BITMAP1));

hBmp hInst are global to the plugin class. hBmp returns 0;

then

SendMessage((HWND)hwndButtonPrevious, (UINT)BM_SETIMAGE, (WPARAM)IMAGE_BITMAP, (LPARAM)hBmp);

The function is called in the CtrlBarWindowProc between two Push/Pop AppContext otherwise not working.

Buttons are responding normally to command and make the job.

But I never had any image on it!

I tried many variations, but nothing happen.

I guess something wrong with hInst, hBmp, or the place where I Send the BM_SETIMAGE message

Any idea?

Pierre

[LeoTaro · Accepted solution]

The LoadBitmap call is failing (hBmp is NULL), because you are using the application HINSTANCE rather than the one for your plugin (dll). Add a DllMain function to your plugin and store the HINSTANCE.

HINSTANCE hDll = NULL;

BOOL APIENTRY DllMain( HINSTANCE hinstDLL, DWORD ul_reason, LPVOID reserved)

{ 

  if (DLL_PROCESS_ATTACH == ul_reason)

       hDll = hinstDLL;

  return TRUE;

}