PrintWindow() API does NOT get an image for Windows created by Java?
Hi
WinXP added the PrintWindow() API that allows one application to take an image copy of another app's window, even if the window is off-screen or obscured, ie beyond the scope of a simple BitBlt. (PrintWindow seems to be a cross-process "extension" of the WM_PRINT message).
But PrintWindow doesn't seem to work when I "point" it at any Java-based apps. That is, for a few java-based apps (including the Java Control Panel) running on XP, the return from PrintWindow includes the non-client area, but the client area is just blackness (not a render of what would be displayed) - the apps do flicker and seem to redraw on the screen instead. Note, I'm not looking for help in using PrintWindow() in a Java app - rather this is perhaps a problem with Java responding to windows painting messages.
I've tried JRE 1.5.0_07-b03 and 1.6.0_01.
Is this a bug in the Java implementation? I'm a bit surprised I can't find any reference to it. Is there a work around?
For a source-code (C++) example of PrintWindow in a small app see http://www.codeguru.com/cpp/g-m/gdi/capturingimages/article.php/c11231
