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iOS Build a Simple iPhone App with Swift Improving Our User Interface Changing the Background Color

Randell Pur
Randell Pur
4,934 Points

I'm not really understanding the question.

So I'm not sure if my code is even correct for this challenge.

ViewController.swift
class ViewController: UIViewController {

  override func viewDidLoad() {
      super.viewDidLoad()
      // Do any additional setup after loading the view, typically from a nib.
  }

  override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
      // Dispose of any resources that can be recreated.
  }

    view.backgroundColor = blueColor
    let blueColor = UIColor(red:0/255.0, green: 0/255.0, blue: 255/255.0, alpha: 1.0)
}

1 Answer

This won't work as when you are trying to change the background the blueColor constant hasn't been defined, to fix this you need to write the declaration of blueColor before assigning the background colour. Like this;

class ViewController: UIViewController {

  override func viewDidLoad() {
      super.viewDidLoad()
      // Do any additional setup after loading the view, typically from a nib.
  }

  override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
      // Dispose of any resources that can be recreated.
  }

    let blueColor = UIColor(red:0/255.0, green: 0/255.0, blue: 255/255.0, alpha: 1.0)
    view.backgroundColor = blueColor
}

Hope this helps. If so mark has the best answer.