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iOS Object-Oriented Swift Classes and Objects Classes and Their Methods

Classes and their method

We need to provide a means to increase the size of our Button. So we are going to add a method named incrementBy which will accept a parameter named points. (Within the method add points to the width and height properties).

The error: Bummer! You forgot to add 'points' to the property 'width' within the 'incrementBy' method.

class Button {
    var width: Double
    var height: Double

    init(width:Double, height:Double){
        self.width = width
        self.height = height
    func incrementBy(points: Double) -> (width: Double, height: Double) {
       return (width + points, height + points)


1 Answer

Dan Johnson
Dan Johnson
40,532 Points

The incrementBy method is suppose to modify the state of the Button instance by incrementing width and height by points. This is all done to the object itself so you don't need to return anything, just change the values.