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()
}

- (void)viewDidLoad
{
    [super viewDidLoad]; 

UITapGestureRecognizer *singleTapGestureRecognizer = [[UITapGestureRecognizer alloc]
                                                          initWithTarget:self
                                                          action:@selector(handleSingleTap:)];
    [singleTapGestureRecognizer setNumberOfTapsRequired:1];
    [singleTapGestureRecognizer requireGestureRecognizerToFail:singleTapGestureRecognizer];

    [self.view addGestureRecognizer:singleTapGestureRecognizer];
}

- (void)handleSingleTap:(UITapGestureRecognizer *)recognizer
{
    [self.view endEditing:YES];
    [textField resignFirstResponder];
    [scrollView setContentOffset:CGPointMake(0, -40) animated:YES];

}

我认为最简单(最好)的方法是子类化全局视图，并使用hitTest:withEvent方法来监听任何触摸。键盘上的触摸没有注册，所以hitTest:withEvent只在你触摸/滚动/滑动/捏…然后调用[self - ending:YES]。

这比使用touchesBegan要好，因为如果你点击视图顶部的按钮，touchesBegan不会被调用。它比无法识别滚动手势的UITapGestureRecognizer更好。它也比使用暗屏更好，因为在复杂和动态的用户界面中，你不能到处都放暗屏。此外，它不会阻止其他动作，你不需要点击两次来选择外面的按钮(就像在UIPopover的情况下)。

此外，这比调用[textField resignFirstResponder]更好，因为你可能在屏幕上有许多文本字段，所以这适用于所有的文本字段。

这个怎么样:我知道这是一个老帖子。它可能会帮助某些人:)

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {  
    NSArray *subviews = [self.view subviews];
    for (id objects in subviews) {
        if ([objects isKindOfClass:[UITextField class]]) {
            UITextField *theTextField = objects;
            if ([objects isFirstResponder]) {
                [theTextField resignFirstResponder];
            }
        } 
    }
}

只是使用这段代码在您的.m文件，它将辞职的文本字段，当用户点击文本字段之外。

 -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
  [textfield resignFirstResponder];
 }

@Jensen2k回答的Swift版本:

let gestureRecognizer : UITapGestureRecognizer = UITapGestureRecognizer.init(target: self, action: "dismissKeyboard")
self.view.addGestureRecognizer(gestureRecognizer)

func dismissKeyboard() {
    aTextField.resignFirstResponder()
}

一个衬套

self.view.addTapGesture(UITapGestureRecognizer.init(target: self, action: "endEditing:"))