CODEWITHSUNDEEP
swiftanimationlabel
Barduco
Barduco

Reputation: 1

How to move a label only once (swift)?

I created a label programmatically, and initially the label don't appear , only when button "appear" is touched (Ok). I want to know how to move the label only once. If the label was moved for the first time, when I touch the button again, nothing must happen.

import UIKit

class ViewController: UIViewController {

var label = UILabel()
var screenWidth: CGFloat = 0.0
var screenHeight: CGFloat = 0.0

override func viewDidLoad() {
    super.viewDidLoad()

    let screenSize: CGRect = UIScreen.mainScreen().bounds
    screenWidth = screenSize.width
    screenHeight = screenSize.height

    label = UILabel(frame: CGRectMake(0, 64, screenWidth, 70))
    label.textAlignment = NSTextAlignment.Center
    label.backgroundColor = UIColor.blackColor()
    label.text = "Label Appear"
    label.font = UIFont(name: "HelveticaNeue-Bold", size: 16.0)
    label.textColor = UIColor.whiteColor()
    view.addSubview(label)


    // Do any additional setup after loading the view, typically from a nib.
}

override func viewWillAppear(animated: Bool) {
    super.viewWillAppear(animated)

    self.label.center.y -= self.view.bounds.width


}
@IBAction func appear(sender: AnyObject) {

    UIView.animateWithDuration(0.5, animations: {

        self.label.center.y += self.view.bounds.width

        }, completion: nil)
}

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


}

Upvotes: 0

Views: 1112

Answers (1)

Aymen Rebouh
Aymen Rebouh

Reputation: 23

One solution is to add a boolean that indicate if the label has already moved or hasn't.

For example :

var hasLabelAlreadyMoved = false
...
@IBAction func appear(sender: AnyObject) {

/* 
We want to move the label if the bool is set to false ( that means it hasn't moved yet ), 
else ( the label has already moved ) we exit the function 
*/
guard !self.hasLabelAlreadyMoved else { 
   return 
}

self.hasLabelAlreadyMoved = true 
UIView.animateWithDuration(0.5, animations: {

    self.label.center.y += self.view.bounds.width

    }, completion: nil)
}

Upvotes: 2

Related Questions