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Grayson Swaim
8,992 PointsdestinationViewController
My question involves the "prepareforSegue" method in which we use the "destinationViewController" attribute to establish a connection between 2 view controllers:
PlayListDetailViewController *playListDetail = (PlayListDetailViewController *)segue.destinationViewController;
What kind of value is the "destinationViewController" returning, and what is the easiest way to verify this?
2 Answers
Chris Shaw
26,676 PointsHi Grayson Swaim,
The value stored within destinationViewController will always be an instance of the subclass UIView, we typically don't need to verify this as all views should be based upon it, however, if you wanted to for instance confirm it's an instance of PlayListDetailViewController before down-casting it.
We can do this by using the isMemberOfClass method which is always available to UIView instances.
UIView *view = segue.destinationViewController;
if ([view isMemberOfClass:[PlayListDetailViewController class]]) {
// view is an instance of `PlayListDetailViewController`
} else {
// view is NOT an instance of `PlayListDetailViewController`
}
Hope that helps.
Iulian Popescu
1,363 PointsFrom Apple doc you can see that destinationViewController type is AnyObject in Swift and id in Objective-C. So, if you want to use it in prepareForSegue you can downcast it to your own view controller and configure it how you want. Good luck!