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Shay Paustovsky
Shay Paustovsky
969 Points

@IBAction methods with or without parameters ?


I was wondering if someone could explain this bit of code :

'''swift @IBAction func sliderMoved(_ slider: UISlider) { print("The value of the slider now is: (slider.value)") }

''' And why do we have a parameter between the parenthesis and if we can remove it and if yes would it make a difference.

Thanks in advance.


1 Answer

Chris Stromberg
Chris Stromberg
Courses Plus Student 13,389 Points

It may help to read up on UIControl and the paragraph titled "The Target-Action Mechanism".


To summarize, you could have more than one interface item connected to your action/method. The sender parameter specifies what object sent the message, or what button was pressed, if more than one button was connected to your action.