ProgressBar仅显示结束

Question

ProgressBar仅显示循环结束时的进度。在这个例子中，如何实时更新条形图？

@IBAction func btnStart(sender: AnyObject) {
    for var xx:Float = 0 ; xx<=1.0; xx=xx+0.00001 {
        progressView.setProgress(xx, animated: false)
    }
}
@IBOutlet weak var progressLabel: UILabel!
@IBOutlet weak var progressView: UIProgressView!

Answer 1

UI仅在主循环和当前作用域的末尾进行更新，

所以试试这个

@IBAction func btnStart(sender: AnyObject) {
    NSThread.detachNewThreadSelector("process", toTarget: self, withObject: nil)
}
func process() {
    for var xx:Float = 0 ; xx<=1.0; xx=xx+0.00001 {
        dispatch_async(dispatch_get_main_queue(), {
            progressView.setProgress(xx, animated: false)
        })
    }
}
@IBOutlet weak var progressLabel: UILabel!
@IBOutlet weak var progressView: UIProgressView!