iOS-键盘弹出或隐藏时调整输入框的位置

要达到自动调整的目标需要监听 keyboardWillShowNotification 跟 keyboardWillHideNotification， 同时需要实现点击其它地方时，通知隐藏键盘的事件

ViewController.swift
viewDidLoad{
　　NotificationCenter.default.addObserver(self, selector:#selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
　　NotificationCenter.default.addObserver(self, selector:#selector(keyboardWillHide), name: UIResponder.keyboardWillHideNotification, object: nil)
　　let tap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action:#selector(self.dismissKeyboard))
　　view.addGestureRecognizer(tap)　　
}

@objc func dismissKeyboard() {

　　view.endEditing(true)

}

@objc func keyboardWillShow(notification: NSNotification) {

　　if let keyboardSize = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {

　　　　if self.view.frame.origin.y == 0 {

　　　　　　self.view.frame.origin.y -= keyboardSize.height

　　　　}

　　}

}

 

@objc func keyboardWillHide(notification: NSNotification) {

　　if ((notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue)!= nil {

　　　　if self.view.frame.origin.y != 0 {

　　　　　　self.view.frame.origin.y = 0

　　　　}

　　}

}

 

PS: 如果模拟器没有虚拟键盘 Hardware ➤ Keyboard ➤ Toggle Software Keyboard 或 Command + K