iOS: Detect when my UIView is add in other view

Question

CustomView *customView = [...];
[self.view addSubview:customView];

I need to detect in my CustomView class when it is added in other views or when my superview changes.

Answer 1

You can use willMoveToSuperview: and didMoveToSuperview to detect when the view is moved around. layoutSubviews will be called when the superview changes frame.

Answer 2

• For a UIView use - (void)didMoveToSuperview
• For a UIViewController use -(void)viewWillAppear:(BOOL)animated

Answer 3

还要在 addsubview 之前分配 Customview 的标签，并通过特定标签进行检测。