如何使objectAtIndex：0始终可见？

Question

I'm trying to create UIView, which I need to be visible in whole application. Only way, how can I do this is, addSubview to UIWindow *window = [[UIApplication sharedApplication].windows objectAtIndex:0] .Im doing it in AppDelegate . So far everthing is fine.

 window = [UIApplication sharedApplication].keyWindow;
[[[window subviews] objectAtIndex:0] addSubview:myView];

It's a small uiview in left bottom corner. In this view I want to play video while you can do other things in background. But when I push another ViewController or even change rootViewController , it disappears and I need to add it again.

Does rootViewController adds to objectAtIndex:0 or when I change rootViewController , it removes everthing? I was tried, readd it in everywhere it disappearing, but there most be a better solution! In other words, how can I add it without possibility loosing it?

Answer 1

Did it disappear or the new views are added on top of it?

Usually the current view controller will always show its own view on top of the window.

If you are showing a background view with image, then there is way to keep a background image in all screen by default ... you have to add it to the window layer,

self.view.window.layer.contents = (id)[backgroundImage CGImage];

Answer 2

I don't think you CAN create a view that floats on top of every view controller in your app. It goes against Apple's design for the way views and view controllers are supposed to function.

You could make your app a single view controller app, with that view controller having a container view the size of the screen. Then you could embed your app's "real view controller tree in that container view using an embed segue. Then you could put your floating view on that topmost view controller and get the effect you want.

Answer 3

Create a new UIWindow and give it a high enough windowLevel (ie. UIWindowLevelStatusBar should do the trick). Then add the view that you want to be visible to the window and finally make it visible by setting the hidden property to NO .