Swift - UIProgressView

import UIKit
var imageView:UIImageView!
class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        //创建ProgressView
        let progressView = UIProgressView(progressViewStyle: .default)
        progressView.frame = CGRect(x: 150, y: 250, width: 200, height: 0)//自定义高度无效，默认为2.0,可通过transform改变高度
         progressView.transform = CGAffineTransform(scaleX: 1.0, y: 3.0)
        //设置默认进度
        progressView.progress = 0.1
        //设置进度，同时有动画效果
        progressView.setProgress(0.8, animated: true)
        //设置UIProgressView颜色
        progressView.progressTintColor = UIColor.red//设置加载进度条颜色
        progressView.trackTintColor = UIColor.gray//设置进度槽颜色
        //将ProgressViewj添加到视图
        self.view.addSubview(progressView)
    }
}