UITextView cursor below frame when changing frame

Question

I have a UIViewCOntrollerthat contains a UITextView. When the keyboard appears I resize it like this:

#pragma mark - Responding to          


        

Answer 1

Anders and Leo Natan have great solutions. However, I needed to modify their answers a little to get the scrolling to work properly with contentInset. The problem I faced was that textViewDidBeginEditing: gets called before keyboardWasShown: so the contentInset change does not get reflected the first time through. Here is what I did:

In .h

@interface NoteDayViewController : UIViewController 
{
    UIEdgeInsets noteTextViewInsets;
    UIEdgeInsets noteTextViewScrollIndicatorInsets;
    CGRect oldRect;
    NSTimer *caretVisibilityTimer;
    float noteViewBottomInset;
}
@property (weak, nonatomic) IBOutlet UITextView *noteTextView;

In .m

- (void)registerForKeyboardNotifications
{
    [[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWasShown:)
                                             name:UIKeyboardDidShowNotification object:nil];

    [[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWillBeHidden:)
                                             name:UIKeyboardWillHideNotification object:nil];
}

- (void)keyboardWasShown:(NSNotification*)aNotification
{
    CGFloat kbHeight = // get the keyboard height following your usual method

    UIEdgeInsets contentInsets = noteTextViewInsets;
    contentInsets.bottom = kbHeight;
    noteTextView.contentInset = contentInsets;

    UIEdgeInsets scrollInsets = noteTextViewScrollIndicatorInsets;
    scrollInsets.bottom = kbHeight;
    noteTextView.scrollIndicatorInsets = scrollInsets;

    [noteTextView setNeedsDisplay];
}

- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{    
    noteTextView.contentInset = noteTextViewInsets;
    noteTextView.scrollIndicatorInsets = noteTextViewScrollIndicatorInsets;   
    [noteTextView setNeedsDisplay];
}

- (void)textViewDidBeginEditing:(UITextView *)textView
{
    oldRect = [noteTextView caretRectForPosition:noteTextView.selectedTextRange.end];
    noteViewBottomInset = noteTextView.contentInset.bottom;
    caretVisibilityTimer = [NSTimer scheduledTimerWithTimeInterval:0.3 target:self selector:@selector(scrollCaretToVisible) userInfo:nil repeats:YES];
}

- (void)textViewDidEndEditing:(UITextView *)textView
{
    [caretVisibilityTimer invalidate];
    caretVisibilityTimer = nil;
}

- (void)scrollCaretToVisible
{
    // This is where the cursor is at.
    CGRect caretRect = [noteTextView caretRectForPosition:noteTextView.selectedTextRange.end];

    // test if the caret has moved OR the bottom inset has changed
    if(CGRectEqualToRect(caretRect, oldRect) && noteViewBottomInset == noteTextView.contentInset.bottom)
    return;

    // reset these for next time this method is called
    oldRect = caretRect;
    noteViewBottomInset = noteTextView.contentInset.bottom;

    // this is the visible rect of the textview.
    CGRect visibleRect = noteTextView.bounds;
    visibleRect.size.height -= (noteTextView.contentInset.top + noteTextView.contentInset.bottom);
    visibleRect.origin.y = noteTextView.contentOffset.y;

    // We will scroll only if the caret falls outside of the visible rect.
    if (!CGRectContainsRect(visibleRect, caretRect))
    {
        CGPoint newOffset = noteTextView.contentOffset;
        newOffset.y = MAX((caretRect.origin.y + caretRect.size.height) - visibleRect.size.height, 0);
        [noteTextView setContentOffset:newOffset animated:NO]; // must be non-animated to work, not sure why
    }
}