OC textField键盘弹起事件

经常用到点击textFiled时弹起键盘，然后 textField工具条也要随之上升，自己做了个简单的例子

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1. 监听键盘弹起收回事件

    //监听键盘弹出事件
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    //监听键盘隐藏事件
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];

2. 实现对应方法

获取键盘的高度时一定要用** objectForKey:UIKeyboardFrameEndUserInfoKey**，切记

#pragma mark - 键盘即将弹出事件处理
- (void)keyboardWillShow:(NSNotification *)notification
{
    //获取键盘信息
    NSDictionary *keyBoardInfo = [notification userInfo];
    
    //获取动画时间
    CGFloat duration = [[keyBoardInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] floatValue];
    
    //获取键盘的frame信息
    NSValue *value = [keyBoardInfo objectForKey:UIKeyboardFrameEndUserInfoKey];
    CGSize keyboardSize = [value CGRectValue].size;
    
    
    [UIView animateWithDuration:duration animations:^{
        CGRect frame = _chatBar.frame;
        frame.origin.y = SCREENHEIGHT - keyboardSize.height - frame.size.height;
        _chatBar.frame = frame;
    } completion:nil];
}

#pragma mark - 键盘即将隐藏事件
- (void)keyboardWillHide:(NSNotification *)notification
{
    
    //获取键盘信息
    NSDictionary *keyBoardInfo = [notification userInfo];
    
    //获取动画时间
    CGFloat duration = [[keyBoardInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] floatValue];
    
    //获取键盘的frame信息
    
    [UIView animateWithDuration:duration animations:^{
        CGRect frame = _chatBar.frame;
        frame.origin.y = SCREENHEIGHT - _chatBar.height;
        _chatBar.frame = frame;
    } completion:nil];
}