Correct and incorrect answer in Swift - swift

Question

I'm making simple quiz app about countries in Europe, I have a map and three buttons below with names of countries, one of them is correct and of course two incorrect. I want to highlight incorrect (if user click incorrect button) button for red and correct for green, if user click correct button I want to highlight it for green and after maybe 5s come back to the same color that was at first. I know how to change button color but I don't know ho do that for 5s and come back to default color. How can I do that ? Below its code that I use to change button color
UIButtonOutlet.Backgroundcolor.Uicolor.green
But its default green, so I can't set my color.

Answer 1

You can try something like this. First declare one UIButton instance in your class and then scheduledTimer after setting backgroundColor of button for correct's and incorrect and store that button reference with button that you have created first.
var selectedButton = UIButton()
Now use this selectedButton when you are setting button's backgroundcolor.
btnOutlet.backgroundcolor = .green //For correct
btnOutlet.backgroundcolor = .red //For incorrect
self.selectedButton = btnOutlet
//Now scheduled the timer for 5.0 sec
Timer.scheduledTimer(timeInterval: 5.0, target: self, selector: #selector(setButtonBGBack), userInfo: nil, repeats: false)
Add the setButtonBGBack method in your class
func setButtonBGBack() {
self.selectedButton.backgroundcolor = .blue //Set to default here
self.selectedButton = UIButton()
}

Answer 2

Lets say you have your code for changing the color which is in the "changeColor" func:
var correctButton: UIButton
func changeColor() {
if correctButton.backgroundColor == .green {
correctButton.backgroundColor = .lightGray //back to original color
}
}
What this essentially does is changes your correct button color back to its default (whatever that may be) if it is green when the func is called.
Now to use this, we can do a little work inside of the IBAction that is connected to each of your buttons:
#IBAction func buttonClicked(sender: UIButton) {
if sender.titleLabel?.text == "Correct Answer" {
button.backgroundColor = .green
correctButton = button //set the correct button variable so the changeColor func can be used
let timer = Timer.init(timeInterval: 5, target: self, selector: #selector(changeColor), userInfo: nil, repeats: false)
} else if sender.titleLabel?.text == "False Answer 1" || sender.titleLabel?.text == "False Answer 2" {
button.backgroundColor = .red
}
}
So in this code, if you click the button that is the correct answer (you can identify this by tag or other means, but I just decided to use its text) then the color is set to green immediately, and then the correctButton variable is set, but then a timer is initiated that after five seconds will call your changeColor func and then change it back to its original color.
Hope this helps :)
Edit:
Of course, my method assumes that you are using the storyboard to create these buttons. If you are creating them programmatically, then NiravD's method will work better.