Detect if default back button in navigation bar is pressed

Question

I know that there are answers to this like make custom button and then make action but I don't want to change the default back button with arrow and I also tried like this:

override func viewWillDisappear(_ animated : Bool) {
    super.viewWillDisappear(animated)
    if self.isMovingFromParentViewController {
     print("something")
    }
}

Here the problem is that this function gets called even if I press on save button that I also have in that view controller. I need to detect only when the back button is pressed

Answer 1

In your viewWillDisappear method, add the isMovingFromParentViewController property:

if self.isMovingFromParentViewController {
    //do stuff, the back button was pressed
}

EDIT: As had pointed out, if you are merely dismissing the view controller when the save button is pressed, you need a Bool value to check if the save button was pressed or the default back button.

At the top of your class, define a Boolean value:

var saveButtonPressed = false

I'm assuming that you have an @IBAction method linked to your save button. If you don't, then I suggest you add that connection.

In that method, set saveButtonPressed equal to true.

Then, in your viewWillDisappear method, add this to the if condition:

if (self.isMovingFromParentViewController && !saveButtonPressed) {
    //do stuff, the back button was pressed
}