Question

我尝试在我的应用程序中执行加载屏幕，并希望它在UILabel中显示加载状态文本，因此我选择viewDidAppear覆盖功能来完成此操作但是结果是它只显示我设置的已完成文本。这是viewDidAppear中的代码：

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(false)
    loadingicon.alpha = 0
    statuslabel.alpha = 0
    loadingicon.alpha = 0
    statuslabel.alpha = 0

    // change 2 to desired number of seconds
    UIView.animate(withDuration: 0.7, animations: {
        //self.imganimation.frame.origin.y -= 150
        self.loadingicon.alpha = 1
        self.statuslabel.alpha = 1
        // self.loadingicon.frame.origin.y -= 50
        // self.statuslabel.frame.origin.y -= 50

    }, completion: nil)

    self.statuslabel.text = "Loading the data"

    sleep(5)

    if CheckInternet.Connection(){
            self.statuslabel.text = "Connection Success"
    } else {
    }
}

正如你所看到的，我试着让系统睡5秒钟，让它一步一步显示我的文字，但是＆＃34;加载数据＆＃34;文字消失了，它只显示＆＃34;连接成功＆＃34;完成该过程后的文本如何处理此问题

Answer 1

使用GCD从当前时间添加延迟。

DispatchQueue.main.asyncAfter(deadline: .now() + 5) {
// Add the code you want to execute after the delay
}

Answer 2

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(false)
    loadingicon.alpha = 0
    statuslabel.alpha = 0
    loadingicon.alpha = 0
    statuslabel.alpha = 0

    // change 2 to desired number of seconds
    UIView.animate(withDuration: 0.7, animations: {
        //self.imganimation.frame.origin.y -= 150
        self.loadingicon.alpha = 1
        self.statuslabel.alpha = 1
        // self.loadingicon.frame.origin.y -= 50
        // self.statuslabel.frame.origin.y -= 50

    }, completion: nil)

    self.statuslabel.text = "Loading the data"

    DispatchQueue.main.asyncAfter(deadline: .now() + 5) {
      if CheckInternet.Connection(){
              self.statuslabel.text = "Connection Success"
      } else {
      }
  }
}

如何在swift中逐步更改UILabel文本

2 个答案: