UIStoryboardSegue animates property in subclass

Question

I have a UIStoryboardSegue subclass for replacing current view controller with next view controller.

As we have a Animates property in interface editor, I want to access this property in the subclass.

My code is following:

class ReplaceSegue: UIStoryboardSegue {

    override func perform() {
        var viewControllers = source.navigationController?.viewControllers.dropLast() ?? []
        viewControllers.append(destination)
        source.navigationController?.setViewControllers(viewControllers.map {$0}, animated: true) // I dont want this `true` to be hardcoded
    }
}

Answer 1

As per comments in UIStoryBoardSegue class

The segue runtime will call +[UIView setAnimationsAreEnabled:] prior to invoking this method, based on the value of the Animates checkbox in the Properties Inspector for the segue.

So obviously you can read the value of animate check box by using

UIView.areAnimationsEnabled

So in my custom segue

class MySegue: UIStoryboardSegue {
    override func perform() {
        debugPrint(UIView.areAnimationsEnabled)
    }
}

This prints false if animate checkbox is unchecked or true if it is checked :)

So in your case

class ReplaceSegue: UIStoryboardSegue {
    override func perform() {
            var viewControllers = source.navigationController?.viewControllers.dropLast() ?? []
            viewControllers.append(destination)
            source.navigationController?.setViewControllers(viewControllers.map {$0}, animated: UIView.areAnimationsEnabled)
    }
}

I hope whats happening is already clear, incase you still have doubt, here is the explanation, iOS checks the animates checkbox value and uses it to set whether animations are enabled or not by calling setAnimationsAreEnabled with the value of animates check box in interface prior to calling perform() method.

So when the control reaches inside perform you can be assured that iOS has already read the value of animates check box and used it to set setAnimationsAreEnabled all you have to do now is to ask areAnimationsEnabled to get the value of animates check box.

So that should provide you the value of animates checkbox :)

Hope it helps :)