The GTK2 File Chooser Dialog looks non native in OSX.But the GTK3 File chooser looks better.Is there a way by which i can migrate the gtk2 app (Mono.mac) to GTK3?
That is up to the GTK bindings with C#. I don't have a lot of knowledge in this area, since this forum is primarily for Xamarin.Mac (Cocoa) applications. You may want to contact this group:
Maybe this will help:
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