Welcome to the Treehouse Community

The Treehouse Community is a meeting place for developers, designers, and programmers of all backgrounds and skill levels to get support. Collaborate here on code errors or bugs that you need feedback on, or asking for an extra set of eyes on your latest project. Join thousands of Treehouse students and alumni in the community today. (Note: Only Treehouse students can comment or ask questions, but non-students are welcome to browse our conversations.)

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today.

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.