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Chase Maddox
Courses Plus Student 5,461 PointsProtocols: Changing Variables Inside a Function
Hi,
I'm not sure how to change the color to the new color. What am I not doing properly?
Thanks, Chase
// Declare protocol here
protocol ColorSwitchable {
func switchColor(_ color: Color)
}
enum LightState {
case on, off
}
enum Color {
case rgb(Double, Double, Double, Double)
case hsb(Double, Double, Double, Double)
}
class WifiLamp: ColorSwitchable {
let state: LightState
var color: Color
func switchColor(_ color: Color) {
var color = color
}
init() {
self.state = .on
self.color = .rgb(0,0,0,0)
}
}
1 Answer
Martin Wildfeuer
Courses Plus Student 11,071 PointsAlmost there!
In the body of your switchColor implementation, however, you are not assigning the passed in color to the color property of WifiLamp.
func switchColor(_ color: Color) {
// This would be a new variable named color, not addressing the WifiLamp color property.
// Moreover color is already the parameter name
var color = color
}
What you really want to do is
func switchColor(_ color: Color) {
self.color = color
}
Please note that self.color is necessary to let the compiler know that you want to assign to the colorproperty of the class. Otherwise it would be ambiguous. Other languages use this to indicate that.
If your parameter name and the property name did not match, you could do it like this:
func switchColor(_ myColor: Color) {
color = myColor
}
Hope that helps :)