如何在iOS swift4的for循环中更改标签文本？

Question

I want to change/reload my label on activity indicator while I am running the for loop. But I am unable to change my label text.

for i in 0..<(tempAry.count)
{
  self.tempLbl.text = "\(i) Task Completed"
}

Answer 1

You can't visible label text from for loop every time, You will visible only last index label.

Time complexity of this for loop is O(1) so execution time of whole for loop is in milliseconds.

So better way to use the Timer to show the text on the label.

Answer 2

Define globally.

var count = 0
var timer: Timer?

In viewDidLoad method add timer.

timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(self.updating), userInfo: nil, repeats: true)

Outside ViewDidLoad method put below method.

@objc func updating() {
        if count >= 100 - 1{
            timer?.invalidate()
            timer = nil
            return
        }

        count += 1
        self.title = "\(count) Task Completed"
    }

Actually previously added answer is working fine.