Handle UITextView adjustments when showing and hiding the keyboard.

gistfile1.m

- (void)handleKeyboardShow:(NSNotification *)notification
{
    NSDictionary *dict = notification.userInfo;
    NSValue *rectValue = dict[UIKeyboardFrameEndUserInfoKey];
    CGRect keyboardRect = [rectValue CGRectValue];
    
    UITextView *activeTextView;
    if ([self.textView1 isFirstResponder]) {
        activeTextView = self.textView1;
    } else if ([self.textView2 isFirstResponder]) {
        activeTextView = self.textView2;
    }
    
    if (CGRectIntersectsRect(keyboardRect, activeTextView.frame)) {
        CGFloat textViewBottom = CGRectGetMaxY(activeTextView.frame);
        CGFloat keyboardTop = CGRectGetMinY(keyboardRect);
        CGFloat heightOffset = textViewBottom - keyboardTop;
        
        [self.scrollView setContentOffset:CGPointMake(0, heightOffset) animated:YES];
    }
}

- (void)handleKeyboardHide:(NSNotification *)notification
{
    [self.scrollView setContentOffset:CGPointZero animated:YES];
}