Move view up when the keyboard appears.

show-hide-keyboard.m

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShown:)
                                                 name:UIKeyboardWillShowNotification object:nil];
    
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillBeHidden:)
                                                 name:UIKeyboardWillHideNotification object:nil];
}

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

- (void)keyboardWillShown:(NSNotification*)aNotification
{
    NSDictionary* userInfo = [aNotification userInfo];
    CGRect keyboardFrame = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    keyboardFrame = [self.view convertRect:keyboardFrame fromView:self.view.window];
    
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[userInfo[UIKeyboardAnimationCurveUserInfoKey] integerValue]];
    [UIView setAnimationBeginsFromCurrentState:YES];
    
    CGRect frame = self.view.frame;
    frame.origin.y += CGRectGetHeight(keyboardFrame);
    self.view.frame = frame;
    
    [UIView commitAnimations];
}

- (void)keyboardWillBeHidden:(NSNotification*)aNotification
{
    NSDictionary* userInfo = [aNotification userInfo];
    CGRect keyboardFrame = [[userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    keyboardFrame = [self.view convertRect:keyboardFrame fromView:self.view.window];
    
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:[userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue]];
    [UIView setAnimationCurve:[userInfo[UIKeyboardAnimationCurveUserInfoKey] integerValue]];
    [UIView setAnimationBeginsFromCurrentState:YES];
    
    CGRect frame = self.view.frame;
    frame.origin.y -= CGRectGetHeight(keyboardFrame);
    self.view.frame = frame;
    
    [UIView commitAnimations];
}