willResizeSubviewsNotification
A notification that posts before a change to the size of some or all subviews of a split view.
Declaration
class let willResizeSubviewsNotification: NSNotification.NameDiscussion
The notification object consists of the NSSplitView object about to resize its subviews.
The userInfo dictionary includes the NSSplitViewDividerIndex key that contains the index of the divider that the split view or the user moves. If the system sends the notification because the user drags a divider, the dictionary also includes the NSSplitViewUserResizeKey key with a value of 1.