1. Declare control

There are two styles of progress bars

• bar
• default
  The two styles work as follows:

self.view.backgroundColor = UIColor.red
progressView = UIProgressView(progressViewStyle: .default)
progressView.frame = CGRect(x: 0, y: 0, width: 200, height: 10)
progressView.layer.position = CGPoint(x: self.view.frame.width/2, y: 90)
progressView.progress = 0.5
self.view.addSubview(progressView)
        
progressView2 = UIProgressView(progressViewStyle: .bar)
progressView2.frame = CGRect(x: 0, y: 0, width: 200, height: 20)
progressView2.layer.position = CGPoint(x: self.view.frame.width/2, y: 110)
progressView2.progress = 0.5
self.view.addSubview(progressView2)

Operation effect:

Progress bar style

2. Enable progress bar loading animation

progressView.setProgress(0.5, animated: true)

3. Change the progress bar color

progressView.progressTintColor = UIColor.green //Progress color
progressView.trackTintColor = UIColor.yellow //Remaining progress colors

Set progress bar color

4. Set the height of progressView

In fact, careful partners should have found that when declaring controls, the height of the first height:10 and the second height: 20 have no difference from the screenshot, so setting the height of progressView cannot achieve the goal, but we can change the scale of progressView to achieve the height change

progressView = UIProgressView(progressViewStyle: .default)
progressView.frame = CGRect(x: 0, y: 0, width: 200, height: 10)
progressView.layer.position = CGPoint(x: self.view.frame.width/2, y: 90)
progressView.setProgress(0.5, animated: true)
progressView.progressTintColor = UIColor.green //Progress color
progressView.trackTintColor = UIColor.yellow //Remaining progress colors
//By changing the height of the progress bar (the width remains the same, and the height becomes twice the default)
progressView.transform = CGAffineTransform(scaleX: 1.0, y: 2.0)
self.view.addSubview(progressView)
        
progressView2 = UIProgressView(progressViewStyle: .bar)
progressView2.frame = CGRect(x: 0, y: 0, width: 200, height: 20)
progressView2.layer.position = CGPoint(x: self.view.frame.width/2, y: 110)
progressView2.progress = 0.5
self.view.addSubview(progressView2)

Change progress bar height

5. Others

Recommend a custom progress bar style: http://www.code4app.com/thread-6304-1-1.html It is implemented in OC. You may need to be familiar with the use of OC control in swift first

Progress bar with small label