How do I get UITextView to scroll properly when the keyboard is visible

Question

I have a UITextView sitting on top of a UIView, and if I tap on it to open it for editing, then the keyboard is blocking the bottom of the view and I can not see it even though I can write in this area. Can I tell the UITextView to have a different scroll area or what is the solution?

Answer 1

Apple has some code samples that deal with this exact situation.

Answer 2

I finally got it working. Here is my solution, can you guys spot any errors in my design?

@synthesize textView = _textView;
@synthesize callbackViewController = _callbackViewController;


-(void)keyboardWasShown:(NSNotification*)aNotification {
    if(keyboardShown) {
        return;
    }

    NSDictionary *info = [aNotification userInfo];

    // Get the size of the keyboard.
    NSValue *aValue = [info objectForKey:UIKeyboardFrameBeginUserInfoKey];
    keyboardSize = [aValue CGRectValue].size;

    // Resize the scroll view (which is the root view of the window)
    CGRect viewFrame = [self.textView frame];

    orientationAtShown = orientation;

    if(orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown) {
        viewFrame.size.height -= keyboardSize.height;
    } else {
        viewFrame.size.height -= keyboardSize.width;
    }

    self.textView.frame = viewFrame;

    // Scroll the active text field into view.
    //CGRect textFieldRect = [activeField frame];
    [self.textView scrollRectToVisible:viewFrame animated:YES];

    keyboardShown = YES;
}

-(void)keyboardWasHidden:(NSNotification*)aNotification {
    if(!keyboardShown) {
        return;
    }

    // Reset the height of the scroll view to its original value
    CGRect viewFrame = [self.textView frame];
    if(orientationAtShown == UIInterfaceOrientationPortrait || orientationAtShown == UIInterfaceOrientationPortraitUpsideDown) {
        viewFrame.size.height += keyboardSize.height;
    } else {
        viewFrame.size.height += keyboardSize.width;
    }

    self.textView.frame = viewFrame;

    keyboardShown = NO;
}

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

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

-(void)viewWillAppear:(BOOL)animated {
    keyboardShown = NO;
    [self registerForKeyboardNotifications];
}

-(void)viewWillDisappear:(BOOL)animated {
    [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
}

// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
    if(keyboardShown) {
        [self keyboardWasHidden:nil];
    }

    orientation = interfaceOrientation;

    CGRect viewFrame = [self.textView frame];
    if(orientation == UIInterfaceOrientationPortrait || orientation == UIInterfaceOrientationPortraitUpsideDown) {
        if(viewFrame.size.width > viewFrame.size.height) {
            CGRect viewFrameFixed = CGRectMake(viewFrame.origin.x, viewFrame.origin.y, viewFrame.size.height, viewFrame.size.width);
            self.textView.frame = viewFrameFixed;
        }
    } else {
        if(viewFrame.size.width < viewFrame.size.height) {
            CGRect viewFrameFixed = CGRectMake(viewFrame.origin.x, viewFrame.origin.y, viewFrame.size.height, viewFrame.size.width);
            self.textView.frame = viewFrameFixed;
        }
    }


    // Return YES for supported orientations
    return YES;
}