How do IOS know which viewController is being viewed and hence need viewWillAppear to be called

Posted by Jim Thio on Stack Overflow See other posts from Stack Overflow or by Jim Thio
Published on 2012-06-26T08:41:50Z Indexed on 2012/06/26 9:16 UTC
Read the original article Hit count: 194

Filed under:

objective-c

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xcode4

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uiviewcontroller

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viewwillappear

How does iOs know?

Does each view has a pointer to it's controller?

What happened?

When we pop a viewController from navigation, does the navigationController arrange which view should be called?

For example:

If I added: [[BNUtilitiesQuick window] addSubview:[BNUtilitiesQuick searchController].view];

viewWillAppear will be called.

However, window doesn't know the viewController. I am passing the view outlet of the controller not the controller. How can iOs 5 knows that it has to call [[BNUtilitiesQuick searchController] viewWillAppear:YES]

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