Plugins view stays black

Ok, I think this should be my last plugin-related question for a while.
My VST-hosting VST-Plugin now works 100% on Windows, but on Mac there’s the following problem: When I open a hosted plugin’s window from my VST-Plugin, the opened plugin’s inner view is just black.

What could this be? Seems like it just doesn’t get repainted for some reason. This error does ofcourse not occur in standalone apps.

Maybe the host isn’t passing it the events correctly for some reason… I assume this plugin’s in its own top-level window, and not inside your own plugin window, right?

Exactly, the plugin is in its own TopLevelWindow.
Their (the plugins’) view is also black when hosting my VST-hosting plugin in JUCE’s PluginHost. The only exception is opening plugins with no editor, so JUCE’s Generic Plugin editor is shown - that actually works! Maybe that is a good hint?

Hmm. Not sure. All I can think is that if you put a carbon window inside a cocoa app you get something like that…

That cannot be the reason, since it’s also black in JUCE 1.46’s PluginHost, which is not Cocoa.

Sorry, this was only my fault.
My code was calling setAlwaysOnTop(true) on the Plugin’s Window AFTER specifying the Plugin’s Component via setContentComponent(). It’s ofcourse not a good idea to do this since it will destroy the old window.
One has to first setAlwaysOnTop(true) and only then specify the Plugin’s GUI via setContentComponent().