iOS开发中收键盘是十分常用的功能，只需一行代码即可为ViewController添加工具条收键盘功能

更重要的是使用catogory，无代码污染。

代码

// UITextField+keyboard.h
// TextFieldKeyBord
//
// Created by luo.h on 15/10/8.
// Copyright 2015年 l.h. All rights reserved.
//

#import

@interface UITextField (keyboard)

+(void)registerTextFieldInView:(UIView *)aView;

@end

//
// UITextField+keyboard.m
// TextFieldKeyBord
//
// Created by luo.h on 15/10/8.
// Copyright 2015年 l.h. All rights reserved.
//

#import "UITextField+keyboard.h"

@implementation UITextField (keyboard)

-(void)addToolbarWitDoneTitle:(NSString*)title
{
UIBarButtonItem *flexibleSpaceLeft = [[UIBarButtonItem alloc]
initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
target:nil
action:nil];

UIBarButtonItem \*doneButton = \[\[UIBarButtonItem alloc\] initWithTitle:title  
                                                               style:UIBarButtonItemStyleDone  
                                                              target:self  
                                                              action:@selector(dismissKeyBord)\];  
\[doneButton  setTintColor:\[UIColor redColor\]\];

UIToolbar \*toolbar = \[\[UIToolbar alloc\] initWithFrame:CGRectMake(0, 0, self.window.frame.size.width, 44.0)\];  
\[toolbar setItems:@\[flexibleSpaceLeft, doneButton\]\];  
\[self setInputAccessoryView:toolbar\];  

}
//查找所有UITextField并添加按钮
+(void)registerTextFieldInView:(UIView *)aView;
{
for (id obj in aView.subviews) {
NSLog(@"obj class: %@",[obj class]);
if ([obj isKindOfClass:[UITextField class]]) {
UITextField* theTextField = (UITextField*)obj;
[theTextField addToolbarWitDoneTitle:@"完成"];

    }  
}  

}

-(void)dismissKeyBord
{
[self resignFirstResponder];
}

@end

使用：

- (void)viewDidLoad {
[super viewDidLoad];

//注册self.view里所有UITextField  
\[UITextField registerTextFieldInView:self.view\];

}

Demo:　https://files.cnblogs.com/files/sixindev/TextFieldKeyBord.zip