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    <p>You shouldn't have a subviews tell its superview much of anything. You should make the superview a delegate of your view class.</p> <pre><code>// MainView MyView *myView = [[MyView alloc] initWithFrame:CGRectMake(...) delegate:self]; </code></pre> <p>Then save the delegate to an instance variable declared by <code>id delegate</code>. When you finish drawing:</p> <pre><code>// MyView - (void)doDrawing { drawStuff(); [delegate didFinishDrawingView:(MyView *)self] } </code></pre> <p>Now back in your MainView, implement this method</p> <pre><code>- (void)didFinishDrawingView:(MyView *)aView; </code></pre> <p>to do what you want.</p> <p>The point of all this is so that the small classes at the fringe of your app (like a small subview) shouldn't need to know how the large classes above them work. This setup allows the view to communicate up the chain, but with a message that conveys its own status instead of a message that instructs other object to do something specific. This is the way Cocoa is structured so that classes can be easily reused and their events can be repurposed however you need them to be.</p> <p>Your superview should know what to do when its subview finishes. The subview should just let people know its finished.</p> <hr> <p>Declare an instance variable in your subview class's header like this:</p> <pre><code>id delegate; </code></pre> <p>Write an initiailizer for your subview class that looks like this:</p> <pre><code>- (id)initWithFrame:(CGRect)frame delegate:(id)aDelegate { [super initWithFrame:frame]; delegate = aDelegate; return self; } </code></pre> <p>Now you have an initializer that will accept a delegate, saves that delegate, and allows you to then call methods on it.</p>
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    1. POHow to message superview in Objective C
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    1. COThanks! Unfortunately it still doesn't work. For this: MyView *myView = [[MyView alloc] initWithFrame:CGRectMake(...) delegate:self]; i get "warning: no '-initWithFrame:delegate:' method found" Maybe i didn't unterstand "Then save the delegate to an instance variable declared by id delegate"?
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    2. COYou have to create a new intializer method to accept a delegate (or any other variables) on init. I've updated my answer with more details about that.
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