我正在尝试为 swift 4
中的 UILabel 数量增加设置动画,我对这种语言还是新手,我想做的是:
for index in 1...500 {
self.lbl_counter.text = "\(index)"
}
值始终为 500 。
我也尝试过这个
for index in 1...500 {
DispatchQueue.main.async{
self.lbl_counter.text = "\(index)"
}
}
what did i miss here to make it animate increasing the numbers ?
最佳答案
尝试以下代码
import UIKit
class ViewController: UIViewController
{
/// Label
private var customLabel : UILabel?
/// MAximum Count to which label will be Updated
private var maxCount : Int?
/// Count which is currently displayed in Label
private var currentCount : Int?
/// Timer To animate label text
private var updateTimer : Timer?
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
customLabel = UILabel()
customLabel?.textColor = .black
/// Add label to View
addConstraints()
/// Start Timer
DispatchQueue.main.async {
self.maxCount = 100
self.currentCount = 0
self.updateTimer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(ViewController.updateLabel), userInfo: nil, repeats: true)
}
}
@objc func updateLabel() {
self.customLabel?.text = String(currentCount!)
currentCount! += 1
if currentCount! > maxCount! {
/// Release All Values
self.updateTimer?.invalidate()
self.updateTimer = nil
self.maxCount = nil
self.currentCount = nil
}
}
func addConstraints(){
/// Add Required Constraints
self.view.addSubview(customLabel!)
customLabel?.translatesAutoresizingMaskIntoConstraints = false
customLabel?.leftAnchor.constraint(equalTo: self.view.leftAnchor, constant: 50).isActive = true
customLabel?.trailingAnchor.constraint(equalTo: self.view.trailingAnchor, constant: -50).isActive = true
customLabel?.heightAnchor.constraint(equalToConstant: 50).isActive = true
customLabel?.topAnchor.constraint(equalTo: self.view.topAnchor, constant: 50).isActive = true
}
}
关于swift - xcode swift 4 数字增加动画?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/50463885/