How to change a button's background color

Question

In this Swift code that I have greatly simplified for posting here:

@IBOutlet weak var outTrig: UIButton!
@IBAction func actTriggerCameras(_ sender: UIButton) {
    Trig()
}

Trig(){
    outTrig.backgroundColor = UIColor.systemRed
}

I attempt to change the Storyboard button's background color to give feedback to the user that touching it registered with the system. But the background color does not change in the iPhone 14 where this code is run. What do I need to do make this change show on the User Interface?

Answer 1

iOS 15 introduced UIButton.Configuration

By default, when you add a button in Storyboard, the button Style is set to Plain.

If the style is Plain, Gray, Tinted or Filled:

you have to use its .configuration property to make changes:

var cfg = outTrig.configuration
cfg?.baseBackgroundColor = .systemRed
outTrig.configuration = cfg

If you change the style to Default:

you can then use the "older" methods:

outTrig.backgroundColor = .systemRed

See Apple's docs here.