Question

I want to know what notification would I get in my CustomView class when this view will be displayed on screen.

CustomView *customView = [[CustomView alloc] init];
[self.view addSubview:customView];
NewViewController *newController = [[NewViewController alloc] init];
[self.navigationController pushViewController:newController animated:YES];

and after some work I pop this viewController.

[self.navigationController popViewControllerAnimated:YES];

I want to know what method in CustomView class will be called when that view will appear again on the screen.

Actually I have an infinite loop animation in that CustomView and on pushing to nextController I have to stop that animation loop and after coming back I need to start it again.

Answer 1

UIView doesn’t get

viewWillAppear
viewDidDisappear 
etc

ViewController in which it’s contained, however, does, so, in order to pass it to UIView you are to implement following method:

- (void)viewWillAppear:(BOOL)animated
{
   [super viewWillAppear:animated];
   [[self.view.subviews objectAtIndex:0] viewWIllAppear]; // i assume your subview is the only one, otherwise you need to know the index, or have it as an ivar/property 
}

Another idea – since you use your view a lot, i assume you do not recreate it. Let it be a property of your [[UIApplication sharedApplication] delegate]. Now you can access it like this:

#define SharedView [(appDelegate*)[[UIApplication sharedApplication] delegate] sharedView];

Then make custom UIViewController and overwrite viewWillAppear:

- (void)viewWillAppear:(BOOL)animated
{
  [super viewWillAppear:animated];
  if ( [SharedView.superview isEqual:self.view] )
  {
     [SharedView viewWillAppear];
  }
}