TextField随着键盘的弹出上移

- (void)viewDidLoad
{

    

    [super viewDidLoad];

    [self setupButtomView];

    [[NSNotificationCenter defaultCenter] addObserver:selfselector:@selector(keyboardWillShow:) name:@"UIKeyboardWillShowNotification" object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:selfselector:@selector(keyboardWillHidden:) name:@"UIKeyboardWillHideNotification" object:nil];

}

//键盘即将出现的时候

16c39
- (void)keyboardWillShow:(NSNotification *)sender{

    

    CGRect keyboardRect
= [(sender.userInfo[UIKeyboardFrameBeginUserInfoKey]) CGRectValue];

    //改变bttomView的y值，防止被键盘遮住

    CGRect bottomViewRect
= self.bottomView.frame;

    bottomViewRect.origin.y = self.view.frame.size.height -
keyboardRect.size.height -
bottomViewRect.size.height;

    self.bottomView.frame =
bottomViewRect;

    

}

//键盘即将消失的时候

- (void)keyboardWillHidden:(NSNotification *)sender{

    

    CGRect bottomViewRect
= self.bottomView.frame;

    bottomViewRect.origin.y = self.view.frame.size.height - 65;

    self.bottomView.frame =
bottomViewRect;

}

//键盘的布局

- (void)setupButtomView{

    self.bottomView =
[[UIView alloc] initWithFrame:CGRectMake(0,self.view.frame.size.height - 65, CGRectGetWidth(self.view.frame),65)];

    self.bottomView.backgroundColor =
[UIColor grayColor];

    [self.view addSubview:self.bottomView];

    //添加textfield

    self.commentTextField =
[[UITextField alloc]initWithFrame:CGRectMake(10, 10, self.view.frame.size.width - 100,45)];

    self.commentTextField.backgroundColor =
[UIColor whiteColor];

    self.commentTextField.layer.cornerRadius = 10;

    [self.bottomView addSubview:self.commentTextField];

    //textField遵循协议

    self.commentTextField.delegate = self;

    //添加button

    self.commentButton =
[UIButton buttonWithType:UIButtonTypeSystem];

    self.commentButton.frame = CGRectMake(self.view.frame.size.width -80, 10, 70, 45);

    self.commentButton.backgroundColor =
[UIColor whiteColor];

    self.commentButton.layer.cornerRadius = 10;

    [self.commentButton setTitle:@"发送" forState:UIControlStateNormal];

    [self.commentButton addTarget:selfaction:@selector(commentButtonAction:)forControlEvents:UIControlEventTouchUpInside];

    [self.bottomView addSubview:self.commentButton];

    //关闭button的用户交互

    self.commentButton.userInteractionEnabled = NO;

}

//发送按钮的回调方法

- (void)commentButtonAction:(UIButton *)sender{

    

    //取消第一响应者

    [self.commentTextField resignFirstResponder];

}

- (void)didReceiveMemoryWarning
{

    [super didReceiveMemoryWarning];

    //
Dispose of any resources that can be recreated.

}

//文本框内容发生变化

- (BOOL)textField:(UITextField *)textField
shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{

    

    //当文本框只有一个字符的时候，我们需要判定该字符是添加的还是需要删除的。如果是添加，需要打开用户交互，如果是删除，需要关闭用户交互

    if (string.length){//添加字符串，打开用户交互

        self.commentButton.userInteractionEnabled = YES;

    }

    else{

        if (textField.text.length <= 1)
{

            self.commentButton.userInteractionEnabled = NO;

        }

    }

    return YES;

 

}