解除键盘通知触发动画的问题

Question

我有一个占位符，当键盘打开和关闭时，我正在制作动画。到目前为止，当键盘打开时，它会正常动画，但是当它关​​闭时它会保持原位。以下是我正在使用的代码。

func setupKeyboardObservers() {

    NotificationCenter.default.addObserver(self, selector: #selector(handleKeyboardNotification), name: NSNotification.Name.UIKeyboardWillShow, object: nil)

    NotificationCenter.default.addObserver(self, selector: #selector(handleKeyboardNotification), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}

设置键盘通知

        let isKeyboardShowing = notification.name == NSNotification.Name.UIKeyboardWillShow
        let isKeybobardNotShowing = notification.name == NSNotification.Name.UIKeyboardWillHide

这是动画发生的地方

        DispatchQueue.main.async {
            if isKeyboardShowing {

                NSLayoutConstraint(item: self.placeholder, attribute: .left, relatedBy: .equal, toItem: self.searchBarView, attribute: .left, multiplier: 1, constant: 5).isActive = true
                UIView.animate(withDuration: 0.5, delay: 0, options: UIViewAnimationOptions.curveEaseOut, animations: {
                    self.view.layoutIfNeeded()
                }, completion: { (completed) in

                })

            }
        }


        DispatchQueue.main.async {
            if isKeybobardNotShowing {

                NSLayoutConstraint(item: self.placeholder, attribute: .centerX , relatedBy: .equal, toItem: self.searchBarView, attribute: .centerX, multiplier: 1, constant: 0).isActive = true
                UIView.animate(withDuration: 0.5, delay: 0, options: UIViewAnimationOptions.curveEaseOut, animations: {
                    self.view.layoutIfNeeded()
                }, completion: { (completed) in

                })

            }
        }

有什么建议吗？

Answer 1

试试这个。添加self.view.layoutIfNeeded（）再一次在你的两个dispatchqueue ...

上面

self.view.layoutIfNeeded()
    DispatchQueue.main.async {
         ....
         self.view.layoutIfNeeded()
        }
    }