How to make the incall overlay not push the ui downwards - ios

Question

I have an iOS app. It works great.
Except when the user has a hotspot on or is in a call but the call app is minimised
The extended height of the status bar pushes my ui down, making part of it disappear,
at the bottom.
I want this extended bar to overlay the top of the screen and not push the ui downwards.
How do I achieve that ?

Answer 1

The Simplest Solution is to make sure that your view's springs-and-struts or Autolayout properties allow for compression or expansion of the view , If you have some complex UI then you can implement UIApplicationWillChangeStatusBarFrameNotification observer.
You can handle the UIApplicationWillChangeStatusBarFrameNotification and UIApplicationDidChangeStatusBarOrientationNotification notifications which will tell you the new size of the status bar.
If you are intent on using a transform on your view to handle resizing, you can implement -viewWillLayoutSubviews in your view controllers (probably in a common base class) to set a transform on the root view of the view controller.
-(void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(statusFrameChanged:)
name:UIApplicationWillChangeStatusBarFrameNotification
object:nil];
}
-(void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
[[NSNotificationCenter defaultCenter] removeObserver:self
name:UIApplicationWillChangeStatusBarFrameNotification
object:nil];
}
- (void)statusFrameChanged:(NSNotification*)note
{
CGRect statusBarFrame = [note.userInfo[UIApplicationStatusBarFrameUserInfoKey] CGRectValue];
CGFloat statusHeight = statusBarFrame.size.height;
UIScreen *screen = [UIScreen mainScreen];
CGRect viewRect = screen.bounds;
viewRect.size.height -= statusHeight;
viewRect.origin.y = statusHeight;
self.view.frame = viewRect;
[self.view setNeedsLayout];
}
- (void)viewWillLayoutSubviews
{
[super viewWillLayoutSubviews];
CGRect baseFrame = self.view.frame;
// 548.0 is the full height of the view. Update as necessary.
CGFloat scale = self.view.frame.size.height / 548.0;
[self.view setTransform:CGAffineTransformMakeScale(1.0, scale)];
self.view.frame = baseFrame;
}

Answer 2

I used use "Vertical space - Bottom layout Guide - Button". This way, a button I have on the bottom of the screen stays in the same place when there is an in call bar and if a different screen size is used (3.5inch or 4icnh).