点按视图即可关闭键盘

如果你想通过在它外面点击来隐藏键盘，可以使用这个 hacky 技巧（仅适用于 Objective-C）：

- (void)viewDidLoad {
    [super viewDidLoad];

    // dismiss keyboard when tap outside a text field
    UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self.view action:@selector(endEditing:)];
    [tapGestureRecognizer setCancelsTouchesInView:NO];
    [self.view addGestureRecognizer:tapGestureRecognizer];
}

对于 Swift，会有更多的代码：

override func viewDidLoad() {
    super.viewDidLoad()

    // dismiss keyboard when tap outside a text field 
    let tapGestureRecognizer: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(YourVCName.dismissKeyboard))
    view.addGestureRecognizer(tapGestureRecognizer)
}

//Calls this function when the tap is recognized.
func dismissKeyboard() {
    //Causes the view (or one of its embedded text fields) to resign the first responder status.
    view.endEditing(true)
}

另一个 Swift 3 / iOS 10 的例子

class vc: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        
        txtSomeField.delegate = self
    }
}

extension vc: UITextFieldDelegate {
    //Hide the keyboard for any text field when the UI is touched outside of the keyboard.
    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?)
    {
        self.view.endEditing(true) //Hide the keyboard
    }
}