我拼凑了几个答案。

使用一个在viewDidLoad期间初始化的ivar:

UIGestureRecognizer *tapper;

- (void)viewDidLoad
{
    [super viewDidLoad];
    tapper = [[UITapGestureRecognizer alloc]
                initWithTarget:self action:@selector(handleSingleTap:)];
    tapper.cancelsTouchesInView = NO;
    [self.view addGestureRecognizer:tapper];
}

删除当前正在编辑的内容:

- (void)handleSingleTap:(UITapGestureRecognizer *) sender
{
    [self.view endEditing:YES];
}

override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {

    if let touch = touches.first{
     view.endEditing(true)

     }
}

在viewDidLoad 斯威夫特4.2 代码是这样的

let viewTap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action:#selector(dismissKeyboard))
        view.addGestureRecognizer(viewTap)
@objc func dismissKeyboard() {
        view.endEditing(true)
    }

这一定是通过触摸外部隐藏键盘的最简单方法:

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    [self.view endEditing:YES];    
}

(从如何解散键盘时，用户点击其他区域以外的文本框?)

你可以为UiView创建类别并重写touchesBegan方法，如下所示。

这对我来说很好。这是一种集中解决这一问题的方法。

#import "UIView+Keyboard.h"
@implementation UIView(Keyboard)

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    [self.window endEditing:true];
    [super touchesBegan:touches withEvent:event];
}
@end

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