Question

我试图在我的视图中添加模糊效果。我像这样创建了模糊效果

let blurLabel: UIVisualEffectView = {
    let blurEffect = UIBlurEffect(style: UIBlurEffectStyle.dark)
    let blurEffectView = UIVisualEffectView(effect: blurEffect)


    return blurEffectView
    }()

然后我像这样将它添加到子视图中，并使用它设置约束

 override init(style: UITableViewCellStyle, reuseIdentifier: String?) {
        super.init(style: .subtitle, reuseIdentifier: reuseIdentifier)
        let view = tableViewCell

        addSubview(view)
        view.addSubview(blurLabel)

 blurLabel.leftAnchor.constraint(equalTo: self.leftAnchor,constant:0).isActive = true
        //blurLabel.topAnchor.constraint(equalTo: self.topAnchor, constant: 178).isActive = true
        blurLabel.widthAnchor.constraint(equalToConstant: 375).isActive = true
        blurLabel.heightAnchor.constraint(equalToConstant: 180).isActive = true

但是当我运行应用程序时，它并没有出现在

中

Answer 1

编辑：正如@HAS＆amp; amp; @Fogmeister，您也可以使用translatesAutoResizingMaskIntoConstraints = false，因为它是使用自动布局而不指定显式帧的更好解决方案。

您必须将框架分配给UIVisualEffectView，如下所示：

 let blurLabel: UIVisualEffectView = {
    let blurEffect = UIBlurEffect(style: UIBlurEffectStyle.dark)
    let blurEffectView = UIVisualEffectView(effect: blurEffect)
    blurEffectView.frame = CGRect(x: 0, y: 0, width: 60, height: 40) //give desirable frame
    return blurEffectView
 }()

Answer 2

如果您愿意，您还可以将“blurView”提供给任何视图或子视图，而不是提供明确的帧。

let blurLabel: UIVisualEffectView = {
    let blurEffect = UIBlurEffect(style: UIBlurEffectStyle.dark)
    let blurEffectView = UIVisualEffectView(effect: blurEffect)    
    blurEffectView.frame = myMainview.bounds //Blur effect's frame
    return blurEffectView
}()

override func viewDidLoad() {
    super.viewDidLoad()
    // Use it somewhere using
    self.view.insertSubview(blurEffectView, belowSubview: myAnotherView)
    // You may also use any of the subviews too, instead of the self.view
    /// self.myView.insertSubview(blurEffectView, belowSubview: myAnotherView)
}

Answer 3

要解决此问题，您只需停止自动创建约束即可。像这样......

let blurLabel: UIVisualEffectView = {
    let blurEffect = UIBlurEffect(style: UIBlurEffectStyle.dark)
    let blurEffectView = UIVisualEffectView(effect: blurEffect)
    // this line will stop constraints being added for a zero frame
    blurEffectView.translatesAutoResizingMaskIntoConstraints = false
    return blurEffectView
}()

模糊效果不出现在UITableViewCell中

3 个答案: