iOS系统键盘和自定义键盘的切换

    // 1. 给UITextView添加一个可点击的UIControl
    UIControl *control = [[UIControl alloc] initWithFrame:_inputView.bounds];
    [control addTarget:self action:@selector(inputViewTapHandle) forControlEvents:UIControlEventTouchUpInside];
    [_inputView addSubview:control];

#pragma mark - 从别的inputView切换为系统键盘
- (void)inputViewTapHandle
{
    MyLog(@"%s", __FUNCTION__);
    [_inputView becomeFirstResponder];
    _inputView.inputView = nil;
    [_inputView reloadInputViews];
}

- (void)addBtnClick
{
    [_inputView resignFirstResponder];
    MyLog(@"%s", __FUNCTION__);
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, 150)];
    view.backgroundColor = [UIColor grayColor];
    _inputView.inputView = view;
    [_inputView becomeFirstResponder];
}

- (void)smileBtnClick
{
    [_inputView resignFirstResponder];
    MyLog(@"%s", __FUNCTION__);
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, SCREEN_WIDTH, 150)];
    view.backgroundColor = [UIColor orangeColor];
    _inputView.inputView = view;
    [_inputView becomeFirstResponder];
}