Is there any way to get the HWND from a window in LWJGL?

Question

I've started some experimentation in Java and LWJGL (via Slick), and it seems very solid. However, I have some legacy code that requires a HWND integer as a parameter. I'm not sure how I'd be able to get this, or if LWJGL would be able to report this for me. Any help?

Answer 1

An hWnd is a Windows API window handle. Here's an example that shows how to get it for an AWT component and does some other stuff (from here):

JNIEXPORT jlong JNICALL Java_test_Transparency_getWindowHandle
  (JNIEnv * env, jclass cls, jobject component)
{
   JAWT awt;
   JAWT_DrawingSurface* ds;
   JAWT_DrawingSurfaceInfo* dsi;
   JAWT_Win32DrawingSurfaceInfo* dsi_win;
   jint dsLock;
   jboolean result = JNI_FALSE;

   // Get the AWT
   awt.version = JAWT_VERSION_1_4;
   result = JAWT_GetAWT(env, &awt);

   if ( result == JNI_FALSE )
   {
      printf( "%s:%i -  JAWT_GetAWT() failed.\n", __FILE__, __LINE__ );
      return 0;
   }

   // Get the drawing surface
   ds = awt.GetDrawingSurface(env, component);

   if ( ds == NULL )
   {
      printf( "%s:%i -  GetDrawingSurface() failed.\n", __FILE__, __LINE__ );
      return 0;
   }

   dsLock = ds->Lock(ds);

   // Get the drawing surface info
   dsi = ds->GetDrawingSurfaceInfo(ds);

   // Get the platform-specific drawing info
   dsi_win = (JAWT_Win32DrawingSurfaceInfo*)dsi->platformInfo;

   HWND handle = dsi_win->hwnd;

   ds->FreeDrawingSurfaceInfo(dsi);
   ds->Unlock(ds);
   awt.FreeDrawingSurface(ds);

   return (jlong)handle;
}