Flutterby™! : Mac development woes

Aaaaugh! You know it's bad when a widget set makes you pine for Windows, in this case it's the wackiness of Apple's "Carbon". Trying to redraw a window? You have two different ways to invalidate the region, depending on whether the window is semi-transparent or not, either via InvalWindowRect(...) or HIViewSetNeedsDisplay(...). Of course neither of these is doing anything for the particular control (that's very explicit about tellling me that it doesn't own any of the data it's a view on), because there I have to call UpdateDataBrowserItems(...).