问题
iOS Notes and Mail apps have a three-pane split view interface on iPad landscape mode. How can I create such interface? I checked UISplitViewController but it made only two panes (master and detail). Can somebody please enlighten me how to create the leftmost pane?
回答1:
It's done using custom layout. You have root view controller that loads three other view controllers into three container views. That is all.
来源：https://stackoverflow.com/questions/47956490/three-pane-split-view-interface-on-ipad-landscape-mode