Hey everyone! I am trying to decide whether I should use C++/Qt or Objective-C/Cocoa for my next project. I am familiar with C++ and Qt, but know nothing about Objective-C/Cocoa (but definitely don't mind learning since mac is becoming my primary target platform). Qt has a pretty good support for model/view architecture, but using it for apps with tree, table, graphics widgets that pull data from the same model seems pretty challenging. So, I am wondering how one would go about organizing such an app with Objective-C/Cocoa. Basically, I want to store train schedules (involving ~20,000 trains) in a model so that (1) The tree widget would display departure cities at the top level, arrival cities on the next level, and finally the corresponding trains. Like this: Paris Athens train A train B train C (2) The table widget would display arrival/departure times and other data for the selected trains. Train selection can be facilitated by adding check boxes to the above tree widget. (3) Graphics widget would visualize the route of the selected trains on a map. I would really appreciate any suggestions! Thank you!