iOS添加键盘弹出监听事件

当键盘弹出时，页面控件需要重新布局，需要获取键盘的高度，添加键盘监听事件

1.在viewDidLoad中添加键盘监听

#pragma mark -键盘弹出添加监听事件
    // 键盘出现的通知
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:) name:UIKeyboardDidShowNotification object:nil];
    // 键盘消失的通知
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillBeHiden:) name:UIKeyboardWillHideNotification object:nil];

2.键盘监听方法

#pragma mark -键盘监听方法
- (void)keyboardWasShown:(NSNotification *)notification
{
    // 获取键盘的高度
    CGRect frame = [[[notification userInfo] objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    CGFloat height = kViewHeight - 64 - frame.size.height;
    
    if (height < 455.5) {
        self.textFiledScrollView.frame = CGRectMake(0, 64, kViewWidth, height);
    }
    
    if (![self.titleTextView.text isEqualToString:@""]) {
        self.titleTextView.contentInset = UIEdgeInsetsMake(0, 0, 0, 0);
    } else {
        self.titleTextView.contentInset = UIEdgeInsetsMake(20, 0, -20, 0);// 光标偏移
    }
    
    [self contentSizeToFit];// 垂直居中
}
- (void)keyboardWillBeHiden:(NSNotification *)notification
{
    self.textFiledScrollView.frame = CGRectMake(0, 64, kViewWidth, 455.5);
}

3.注意要在dealloc中，需要移除

- (void)dealloc
{
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardDidShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];    
}

代码仅供参考。