How do I reset NSSplitView views

Question

This is a little hard to explain, but I will try my best.

This is how I setup my NSSplitView inside my mainWindow.

[self.splitView.subviews[0] addSubview:view0];
[self.splitView.subviews[1] addSubview:view1];
[self.splitView.subviews[2] addSubview:view2];

However, if I close the mainWindow and reopen it the views do not "reset" so to speak. It still has previous information for a little while until my app retrieves new information. Is there an elegant way to reset NSSplitView views? Thank you for any tips you might have.

Edit: I tried releasing my MainWindow, but if I do that I can't reopen the the window.