Here's the problem: I have some existing old Logic projects that use my plugin (pre Logic Pro X and pre Juce). I now have a new Juce based version of the AU plugin based on a very recent Juce tip and generated from IntroJucer. The old projects open fine and play correctly, but when I click to open the editor (a custom editor based on Juce's AudioProcessorEditor) nothing pops up.
However, if I create a brand new Logic Pro X project and create a new instance of my plugin, there is no problem. The editor pops up just fine. In addition, this problem only shows up in Logic Pro X -- i.e. not in DP using AU, for example. Another additional mystery: if I open Logic Pro X and create a brand new project with a new instance of my plugin, and then, without shutting down the new project, open up my old project also, then the editor also pops up just fine in my old project. If I then resave my old project in this new healthy state, even with the editor closed, then shut down Logic X completely and reopen it and my newly saved old project, then the editor also pops up correctly. So something in the saved state has changed and allowed the pop up to occur.
I have done some Xcode debugging with breakpoints. When I double click to open the editor in the case where no editor pops up, I see that all the Juce code that generates the AU View appears to work correctly. So, I imagine this is something within Logic that is stuck when opening the old project alone but becomes unstuck when creating a new project in the same Logic process and then remains unstuck after saving and reopening.
I am concerned about this because I want to release this version of the plugin based on Juce but I have a number of existing customers in the field with existing projects, and I would prefer this problem be solved without needing the ackward work around.