objective-c : resize UITextView when showing keyboard

resize UITextView when showing keyboard.m

//resize UITextView when showing keyboard

- (void)keyboardWillShow:(NSNotification *)aNotification {
    [self moveTextViewForKeyboard:aNotification up:YES];
}

- (void)keyboardWillHide:(NSNotification *)aNotification {
    [self moveTextViewForKeyboard:aNotification up:NO]; 
}

- (void) moveTextViewForKeyboard:(NSNotification*)aNotification up: (BOOL) up
{
    NSDictionary* userInfo = [aNotification userInfo];

    // Get animation info from userInfo
    NSTimeInterval animationDuration;
    UIViewAnimationCurve animationCurve;

    CGRect keyboardEndFrame;

    [[userInfo objectForKey:UIKeyboardAnimationCurveUserInfoKey] getValue:&animationCurve];
    [[userInfo objectForKey:UIKeyboardAnimationDurationUserInfoKey] getValue:&animationDuration];
    [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] getValue:&keyboardEndFrame];

    // Animate up or down
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:animationDuration];
    [UIView setAnimationCurve:animationCurve];

    CGRect newFrame = textView.frame;
    CGRect keyboardFrame = [self.view convertRect:keyboardEndFrame toView:nil];

    newFrame.size.height -= keyboardFrame.size.height * (up? 1 : -1);
    textView.frame = newFrame;

    [UIView commitAnimations];
}