隐藏按钮上的 IOS 键盘

Question

我想监控 IOS 上的键盘隐藏按钮并触发一个事件。我在说:

我只想在用户按下实际按钮时进行监控。我不想要键盘隐藏时的事件。

Answer 1

用户键盘通知观察者..

对于 swift

NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillAppear"), name: UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide"), name: UIKeyboardWillHideNotification, object: nil)


func keyboardWillAppear() {
    println("Keyboard appeared")
}

func keyboardWillHide() {
    println("Keyboard hidden")
}

针对 Objective-C

[[NSNotificationCenter defaultCenter] addObserver:self 
                                     selector:@selector(keyboardWillShow:) 
                                         name:UIKeyboardWillShowNotification 
                                       object:nil];
// register for keyboard notifications
[[NSNotificationCenter defaultCenter] addObserver:self 
                                     selector:@selector(keyboardWillHide:) 
                                         name:UIKeyboardWillHideNotification 
                                       object:nil];