How do I add a UIView as a subview of the topmost view without knowing which view it is?

Question

I want to add a view:

[aView addSubview:myNewView];

What I am trying to do is find what view is the topmost view being displayed at any given moment, so I can dynamically add a view on top of it. For example, let's say my view stack looks like this:

Modal Camera View (on top of everything, currently being displayed)
TabView
Navigation View
View
TableView

I want to dynamically put something on top of whatever view is at 0.

Does anyone know how to do this or if it's even possible?

[self.view subviews] returns an NSArray. You can access the view at index 0 by [self.view subviewAtIndex:0]; — Zen, Jun 05 '13 at 20:03
Do you mean in general, or are you specifically trying to overlay a view ontop of the view from a `UIImagePickerController`? — Graham, Jun 05 '13 at 20:05

score 3 · Accepted Answer · edited May 23 '17 at 11:58

The view hierarchy is not represented by a stack but by a tree, so there is nothing as the topmost view.

If you just want to add a view on top of all other views, add it to UIWindow as done in this answer :

UIWindow* mainWindow = [[UIApplication sharedApplication] keyWindow];
[mainWindow addSubview:myNewView];

If by view you really meant view controller, then I don't think there way to "walk" the current stack because it would depend on the classes of the stacked view controllers, and also for the same reason as the view hierachy: a view controller could have many childs - a UITabBarController for example.

Exactly what I needed. Thank you. – Ethan Allen Jun 05 '13 at 20:47 — Ethan Allen, Jun 05 '13 at 20:47

How do I add a UIView as a subview of the topmost view without knowing which view it is?

1 Answers1