你需要添加一个UITapGestureRecogniser并将其分配给视图，然后在它的选择器上的UITextField上调用resign first responder。

代码:

在viewDidLoad

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(dismissKeyboard)];

[self.view addGestureRecognizer:tap];

在dismissKeyboard:

-(void)dismissKeyboard 
{
    [aTextField resignFirstResponder];
}

(其中，aTextField是负责键盘的文本字段)

Swift 3版本是这样的

let tapGesture = UITapGestureRecognizer(target: self, action: #selector(self.dismissKeyboard (_:)))
self.view.addGestureRecognizer(tapGesture)

对于dismissKeyboard

@objc func dismissKeyboard (_ sender: UITapGestureRecognizer) {
    aTextField.resignFirstResponder()
}

最好是让你的UIView成为UIControl的一个实例(在界面构建器中)，然后连接他们的TouchUpInside事件来解散键盘方法。这个IBAction方法看起来像:

- (IBAction)dismissKeyboard:(id)sender {
    [aTextBox resignFirstResponder];
}

你需要添加一个UITapGestureRecogniser并将其分配给视图，然后在它的选择器上的UITextField上调用resign first responder。

代码:

在viewDidLoad

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(dismissKeyboard)];

[self.view addGestureRecognizer:tap];

在dismissKeyboard:

-(void)dismissKeyboard 
{
    [aTextField resignFirstResponder];
}

(其中，aTextField是负责键盘的文本字段)

Swift 3版本是这样的

let tapGesture = UITapGestureRecognizer(target: self, action: #selector(self.dismissKeyboard (_:)))
self.view.addGestureRecognizer(tapGesture)

对于dismissKeyboard

@objc func dismissKeyboard (_ sender: UITapGestureRecognizer) {
    aTextField.resignFirstResponder()
}

斯威夫特4

用这个扩展方法设置你的UIViewController，例如在viewDidLoad中:

override func viewDidLoad() {
    super.viewDidLoad()
    self.setupHideKeyboardOnTap()
}

即使点击导航栏，键盘也会被取消。

import UIKit
extension UIViewController {
    /// Call this once to dismiss open keyboards by tapping anywhere in the view controller
    func setupHideKeyboardOnTap() {
        self.view.addGestureRecognizer(self.endEditingRecognizer())
        self.navigationController?.navigationBar.addGestureRecognizer(self.endEditingRecognizer())
    }

    /// Dismisses the keyboard from self.view
    private func endEditingRecognizer() -> UIGestureRecognizer {
        let tap = UITapGestureRecognizer(target: self.view, action: #selector(self.view.endEditing(_:)))
        tap.cancelsTouchesInView = false
        return tap
    }
}

在swift 5中，你可以使用以下代码来解除文本域外的键盘

override func viewDidLoad() {
    // ... code

    let tapGesture = UITapGestureRecognizer(target: self, action: #selector(self.dismissKeyboard(_:)))
    self.view.addGestureRecognizer(tapGesture)  
}

@objc func dismissKeyboard(_ sender: UITapGestureRecognizer) {
    self.view.endEditing(true)
}

override func touchesBegan(touches: Set<NSObject>, withEvent event: UIEvent) {
    super.view.endEditing(true)
    super.touchesBegan(touches, withEvent: event)
}