如果我们告诉视图控制器的视图结束编辑，我们也可以让“user touched somewhere else”解决方案更简单:

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

      [self.view endEditing:YES]; //YES ignores any textfield refusal to resign
 }

．.． 假设“触摸其他地方会取消键盘”是视图中任何其他可编辑字段所期望的行为。

所有这些关于找到键盘视图并在第三行添加done按钮的实现(这就是为什么按钮。y = 163 b/c键盘的高度是216)是脆弱的，因为iOS不断改变视图层次结构。例如，上述代码都不适用于iOS9。

我认为更安全的方法是找到最顶层的视图，通过[[UIApplication sharedApplication] windows] lastObject]，并在它的左下角添加按钮，doneButton.frame = CGRectMake(0, screen_height - 53,106,53);//人像模式

这是最新的代码。只包括 在你的viewController中导入"UIViewController+NumPadReturn.h"

这里是。h

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>

@interface UIViewController (NumPadReturn)



@end

还有。m

#import "UIViewController+NumPadReturn.h"


@implementation UIViewController (NumPadReturn)

-(void) viewDidLoad{
    // add observer for the respective notifications (depending on the os version)
    if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 3.2) {
        [[NSNotificationCenter defaultCenter] addObserver:self 
                                                 selector:@selector(keyboardDidShow:) 
                                                     name:UIKeyboardDidShowNotification 
                                                   object:nil];     
    } else {
        [[NSNotificationCenter defaultCenter] addObserver:self 
                                                 selector:@selector(keyboardWillShow:) 
                                                     name:UIKeyboardWillShowNotification 
                                                   object:nil];
    }

}


- (void)keyboardWillShow:(NSNotification *)note {
    // if clause is just an additional precaution, you could also dismiss it
    if ([[[UIDevice currentDevice] systemVersion] floatValue] < 3.2) {
        [self addButtonToKeyboard];
    }
}

- (void)keyboardDidShow:(NSNotification *)note {
    // if clause is just an additional precaution, you could also dismiss it
    if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 3.2) {
        [self addButtonToKeyboard];
    }
}

- (void)addButtonToKeyboard {
    // create custom button
    UIButton *doneButton = [UIButton buttonWithType:UIButtonTypeCustom];
    doneButton.frame = CGRectMake(0, 163, 106, 53);
    doneButton.adjustsImageWhenHighlighted = NO;
    if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 3.0) {
        [doneButton setImage:[UIImage imageNamed:@"DoneUp3.png"] forState:UIControlStateNormal];
        [doneButton setImage:[UIImage imageNamed:@"DoneDown3.png"] forState:UIControlStateHighlighted];
    } else {        
        [doneButton setImage:[UIImage imageNamed:@"DoneUp.png"] forState:UIControlStateNormal];
        [doneButton setImage:[UIImage imageNamed:@"DoneDown.png"] forState:UIControlStateHighlighted];
    }
    [doneButton addTarget:self action:@selector(doneButton:) forControlEvents:UIControlEventTouchUpInside];
    // locate keyboard view
    UIWindow* tempWindow = [[[UIApplication sharedApplication] windows] objectAtIndex:1];
    UIView* keyboard;
    for(int i=0; i<[tempWindow.subviews count]; i++) {
        keyboard = [tempWindow.subviews objectAtIndex:i];
        // keyboard found, add the button
        if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 3.2) {
            if([[keyboard description] hasPrefix:@"<UIPeripheralHost"] == YES)
                [keyboard addSubview:doneButton];
        } else {
            if([[keyboard description] hasPrefix:@"<UIKeyboard"] == YES)
                [keyboard addSubview:doneButton];
        }
    }
}

- (void)doneButton:(id)sender {
    NSLog(@"doneButton");
    [self.view endEditing:TRUE];
}



@end

我在这里描述了iOS 4.2+的一个解决方案，但键盘出现后，解散按钮会消失。这并不可怕，但也不理想。

上面链接的问题中描述的解决方案包括一种更优雅的消除按钮的错觉，我将按钮淡出并垂直移动，以提供键盘和按钮一起消除的外观。

这是我遇到的最简单的解决办法。我是从《iOS 5开发入门》这本书中学到的。

假设数字字段名为numberField。

In ViewController, add the following method: -(IBAction)closeKeyboard:(id)sender; In ViewController.m, add the following code: -(IBAction)closeKeyboard:(id)sender { [numberField resignFirstResponder]; } Go back to nib file. Open Utilities pan. Open the Identity inspector under Utilities pan. Click on the View (in nib file) once. Make sure you have not clicked on any of the items in the view. For the sake of clarification, you should see UIView under Class in Identity inspector. Change the class from UIView to UIControl. Open Connection Inspector. Click and drag Touch Down and drop the arrow on File Owner icon. (FYI... File Owner icon is displayed on the left of View and appears as a hollow cube with yellow frame.) Select the method: closeKeyboard. Run the program.

现在，当你点击视图背景的任何地方，你应该能够解散键盘。

希望这能帮助你解决问题。: -)

最简单的方法是:创建自定义透明按钮并将其放置在左下角，它将具有与UIKeyboardTypeNumberPad中的空白空间相同的CGSize。切换(显示/隐藏)这个按钮在textField成为firstresponder，按钮点击分别。