Drag handles on different containers in NSWindow

I have an NSTextView with an NS开发者_如何学PythonTableView in a window. I'd like to be able to have those handles that allow you to drag the separator and resize the two adjacent views. I'm new to the cocoa and generally UI design on mac, so am having trouble with finding something as basic as this. I say 'basic' since I see this on pretty much every mac app I've ever used.

Like Skim.app has left and right panes for notes and contents, and both can be resized with the pdf view in the middle expanding or contracting accordingly.

Apologies for not using the right UI lingo to describe the problem.

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I think you're looking for NSSplitView.