Check the following image, how can I add this kind of bar to my own NSTableViews? Other uses are in the network preferences app. What's the magic trick to make this work?
I don't think there is any "magic trick." This is something you will have to implement yourself.
It looks like a group of Gradient style NSButtons placed below the table view. An NSSegmentedControl in Small Square style would work too.
来源：https://stackoverflow.com/questions/9621661/how-do-you-add-a-toolbar-to-the-bottom-of-an-nstableview