IOS开发（21）关于UITextField的键盘遮挡问题

1 前言
平时做App的时候总会遇到，UITextField的键盘会遮挡住下面的内容，由于IOS没有自己的机制，所以需要自己写方法来控制，今天我们就介绍一种简单的方法，来应对键盘遮挡问题。

2 代码实例
ZYViewController.h

[plain]
#import <UIKit/UIKit.h>

@inte易做图ce ZYViewController : UIViewController<UITextFieldDelegate>

@property(nonatomic,strong) UITextField *myTextField;

@end

#import <UIKit/UIKit.h>

@inte易做图ce ZYViewController : UIViewController<UITextFieldDelegate>

@property(nonatomic,strong) UITextField *myTextField;

@end
ZYViewController.m

[plain]
@synthesize myTextField;

- (void)viewDidLoad
{
    [super viewDidLoad];
    //Do any additional setup after loading the view, typically from a nib.
    //self.view.backgroundColor = [UIColor underPageBackgroundColor];
    myTextField = [[UITextField alloc] init];//初始化UITextField
    myTextField.frame = CGRectMake(35, 230, 250, 35);
    myTextField.delegate = self;//设置代理
    myTextField.borderStyle = UITextBorderStyleRoundedRect;
    myTextField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;//垂直居中
    myTextField.placeholder = @"Please entry your content!";//内容为空时默认文字
    myTextField.returnKeyType = UIReturnKeyDone;//设置放回按钮的样式
    myTextField.keyboardType = UIKeyboardTypeNumbersAndPunctuation;//设置键盘样式为数字
    [self.view addSubview:myTextField];


    //注册键盘出现与隐藏时候的通知
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboadWillShow:)
                                             name:UIKeyboardWillShowNotification
                                             object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillHide:)
                                          name:UIKeyboardWillHideNotification
                                          object:nil];
    //添加手势，点击屏幕其他区域关闭键盘的操作
    UITapGestureRecognizer *gesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(hideKeyboard)];
    gesture.numberOfTapsRequired = 1;//手势敲击的次数
    [self.view addGestureRecognizer:gesture];
}

//键盘出现时候调用的事件
-(void) keyboadWillShow:(NSNotification *)note{
    NSDictionary *info = [note userInfo];
    CGSize keyboardSize = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;//键盘的frame
    CGFloat offY = (460-keyboardSize.height)-myTextField.frame.size.height;//屏幕总高度-键盘高度-UITextField高度
    [UIView beginAnimations:nil context:NULL];//此处添加动画，使之变化平滑一点
    [UIView setAnimationDuration:0.3];//设置动画时间秒为单位
    myTextField.frame = CGRectMake(35, offY, 250, 35);//UITextField位置的y坐标移动到offY
    [UIView commitAnimations];//开始动画效果

}
//键盘消失时候调用的事件
-(void)keyboardWillHide:(NSNotification *)note{
    [UIView beginAnimations:nil context:NULL];//此处添加动画，使之变化平滑一点
    [UIView setAnimationDuration:0.3];
    myTextField.frame = CGRectMake(35, 230, 250, 35);//UITextField位置复原

    [UIView commitAnimations];
}
//隐藏键盘方法
-(void)hideKeyboard{
    [myTextField resignFirstResponder];
}
#pragma mark -
#pragma mark UITextFieldDelegate
//开始编辑：
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
    return YES;
}

//点击return按钮所做的动作：
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
    [textField resignFirstResponder];//取消第一响应
    return YES;
}

//编辑完成：
- (void)textFieldDidEndEditing:(UITextField *)textField
{

}

-(void)viewDidDisappear:(BOOL)animated{
    [super viewDidDisappear:animated];
    [[NSNotificationCenter defaultCenter] removeObserver:self];//移除观察者
}

@synthesize myTextField;

- (void)viewDidLoad
{
    [super viewDidLoad];
//Do any additional setup after loading the view, typically from a nib.
    //self.view.backgroundColor = [UIColor underPageBackgroundColor];
    myTextField = [[UITextField alloc] init];//初始化UITextField
    myTextField.frame = CGRectMake(35, 230, 250, 35);
    myTextField.delegate = self;//设置代理
    myTextField.borderStyle = UITextBorderStyleRoundedRect;
    myTextField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;//垂直居中
    myTextField.placeholder = @"Please entry your content!";//内容为空时默认文字
    myTextField.returnKeyType = UIReturnKeyDone;//设置放回按钮的样式
    myTextField.keyboardType = UIKeyboardTypeNumbersAndPunctuation;//设置键盘样式为数字
    [self.view addSubview:myTextField];


&nbs

补充：移动开发 , IOS ,