Copying UIAlertController button behaviour - ios

Question

I am creating custom dialogs for my app and some what copying UIAlertController in some aspects. How should I implement the behaviour where when you click any action from alert/dialog the controller is dismissed.
How does Apple do it without making us manually specify for each action handler that it should dismiss the view controller?
I have like them one view controller class:
#interface MyAlertViewController : UIViewController
- (void)addAction:(MyAlertAction *) action;
//...
And one class for the actions:
#interface MyAlertAction : NSObject
- (instancetype)initWithTitle:(nullable NSString *)title handler:(void (^)(MyAlertAction *action))handler;
EDIT: How I did it taking in accord the answer feedback:
//MYAlertViewController.m
- (void)viewDidLoad {
for (int i = 0; i < self.actions.count; i++) {
MYAlertAction *action = self.actions[i];
button = [[UIButton alloc] initWithFrame:CGRectZero];
button.tag = i;//this here is how I link the button to the action
[button addTarget:self action:#selector(executeAction:) forControlEvents:UIControlEventTouchUpInside];
[actionStackView addArrangedSubview:button];
[self.actionsStackView addArrangedSubview:actionLayout];
}
}
- (void)executeAction:(UIButton *) sender{
[self dismissViewControllerAnimated:YES completion:^{
//this is where the button tag comes in handy
MYAlertAction *actionToExecute = self.actions[sender.tag];
actionToExecute.actionHandler();
}];
}

Answer 1

How does Apple do it without making us manually specify for each action handler that it should dismiss the view controller?
You are confusing two different things:
The UIAlertAction's last initialization parameter, the handler parameter, which you get to set from outside, and which is to run after the button is tapped and after the alert has been dismissed. It is a block.
The actual button's action, which the client can't set or see. It is configured by the alert controller. It is a selector.
So now, you play the role of the UIAlertController. In your
- (instancetype)initWithTitle:(nullable NSString *)title handler:(void (^)(MyAlertAction *action))handler;
the client hands you the first action I mentioned, the block, and you store it for later execution. But the second action, the button action, the selector, is entirely up to you as you create the button in response to this call.
So as you configure the button, just configure it with a target/action pair that calls into a method of your view controller, just as for any button. In method, when called, the view controller dismisses itself, and in the completion handler of the dismissal, calls the block.