Carbon, LSUIElement, and showing a window
- by James Turner
I have a Carbon LSUIElement application, which runs in the background (possibly with an icon in the menubar, depending on a pref) and occasionally needs to show a dialog to the user - sometimes in response to a user event, but sometimes in response to a background task failing or similar.
(I'm using Qt 4.5, so the application is Carbon based; With Qt 4.6 things will be Cocoa based, but it sounds as if the problem may exist there too).
The problem is that when I open a window, and show it, it doesn't get brought to the front. I assume this is an artefect of being an LSUIElement app. Qt uses SelectWindow in Carbon, and [makeKeyAndOrderFront] in Cocoa, to bring a window (and the app) to the front.
To work around the problem, I tried going direct to the window server: (the first few steps are to get the WindowID, this will be simpler with Qt-Cocoa, since I can use NSWindow:nativeWindow)
WindowRef ref = HIViewGetWindow((HIViewRef) aWidget->winId());
CGSWindow wid = GetNativeWindowFromWindowRef(ref);
CGSConnection cid =_CGSDefaultConnection();
CGSOrderWindow(cid, wid, 1 /* above everything */, 0 /* NULL */);
This works, sort of - the window comes to the front, but it's not highlighted or keyboard focused. Are there additional steps to fix those issues, or is there a simpler solution to the whole problem?