[native_samples]

I think the criticisms of layouts are fair. WRT native UI, there's SWT which was used by Jetbrain's primary competitor Eclipse, but obviously users didn't care that the widgets were native because in the end IntelliJ has a much higher market share.

This is probably because not many apps really use native widgets anymore on any platform. It's not even clear what the native UI toolkit on Windows is anymore, due to the numerous aborted attempts to replace Win32 that didn't quite take off.

The Swing widgets IntelliJ uses aren't any worse than native widgets and some are actually much better, for example, any tree view in IntelliJ supports excellent typeahead search, many text inputs are in fact full blown code editors and so on. I don't feel I'm missing anything by them not being Cocoa.