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- (void)addKeyboardObserver{    // This could be in an init method.    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidShow:) name:UIKeyboardDidShowNotification object:nil];    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardDidHide:) name:UIKeyboardDidHideNotification object:nil];}- (void)keyboardDidShow:(NSNotification*)notification{    NSDictionary* keyboardInfo = [notification userInfo];    NSValue* keyboardFrameBegin = [keyboardInfo valueForKey:UIKeyboardFrameBeginUserInfoKey];    _keyboardFrameBeginRect = [keyboardFrameBegin CGRectValue];    UIScrollView *_scrollView = (UIScrollView*)self.view;    _scrollView.frame = CGRectMake(_scrollView.frame.origin.x,                                   _scrollView.frame.origin.y,                                   _scrollView.frame.size.width,                                   _scrollView.frame.size.height - _keyboardFrameBeginRect.size.height);}- (void)keyboardDidHide:(NSNotification*)notification{    UIScrollView *_scrollView = (UIScrollView*)self.view;    _scrollView.frame = CGRectMake(_scrollView.frame.origin.x,                                   _scrollView.frame.origin.y,                                   _scrollView.frame.size.width,                                   _scrollView.frame.size.height +                               _keyboardFrameBeginRect.size.height);}

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 (void)textViewDidChange:(UITextView *)textView{    UIScrollView *_scrollView = (UIScrollView*)self.view;    _textView.frame = CGRectMake(_textView.frame.origin.x,                                 _textView.frame.origin.y,                                 _textView.contentSize.width,                                 _textView.contentSize.height);    _scrollView.contentSize = _textView.frame.size;    if (_scrollView.frame.size.height < _textView.frame.size.height) {        CGPoint bottomOffset = CGPointMake(0,_textView.frame.size.height-_keyboardFrameBeginRect.size.height);        [_scrollView setContentOffset:bottomOffset animated:NO];    }}

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