Programmatically align a toolbar on top of the iPhone keyboard

Question

As of iOS 3.2 there's a new way to achieve this effect:

UITextFields and UITextViews have an inputAccessoryView property, which you can set to any view, that is automatically displayed above and animated with the keyboard.

Note that the view you use should neither be in the view hierarchy elsewhere, nor should you add it to some superview, this is done for you.

So basically:

In the init method:

NSNotificationCenter *nc = [NSNotificationCenter defaultCenter];
[nc addObserver:self selector:@selector(keyboardWillShow:) name: UIKeyboardWillShowNotification object:nil];
[nc addObserver:self selector:@selector(keyboardWillHide:) name: UIKeyboardWillHideNotification object:nil];

And then have methods referred to above to adjust the position of the bar:

-(void) keyboardWillShow:(NSNotification *) note
{
    CGRect r  = bar.frame, t;
    [[note.userInfo valueForKey:UIKeyboardBoundsUserInfoKey] getValue: &t];
    r.origin.y -=  t.size.height;
    bar.frame = r;
}

Could make it pretty by animating the position change by wrapping it in

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDuration:0.3];
//...
    [UIView commitAnimations];

This is based on the existing answer from tonklon - I'm just adding a code snippet that shows a semi transparent black toolbar on top of the keyboard, together with a "done" button on the right:

UIToolbar *toolbar = [[[UIToolbar alloc] init] autorelease];
[toolbar setBarStyle:UIBarStyleBlackTranslucent];
[toolbar sizeToFit];

UIBarButtonItem *flexButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:self action:nil];
UIBarButtonItem *doneButton =[[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(resignKeyboard)];

NSArray *itemsArray = [NSArray arrayWithObjects:flexButton, doneButton, nil];

[flexButton release];
[doneButton release];
[toolbar setItems:itemsArray];

[aTextField setInputAccessoryView:toolbar];

and the -resignKeyboard looks like:

-(void)resignKeyboard {
  [aTextField resignFirstResponder];
}

Hope that helps someone.

If you register for keyboard notifications, ie UIKeyboardWillShowNotification UIKeyboardWillHideNotification, etc, the notification you receive will contain the bounds of the keyboard in the userInfo dict (UIKeyboardBoundsUserInfoKey).

See the UIWindow class reference.

In 3.0 and above you can get the animation duration and curve from the userInfo dictionary of the notifications.

for instance, to animate the size of the view to make room for the keyboard, register for the UIKeyboardWillShowNotification and do something like the following:

- (void)keyboardWillShow:(NSNotification *)notification
{
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationCurve:[[[notification userInfo] objectForKey:UIKeyboardAnimationCurveUserInfoKey] intValue]];
    [UIView setAnimationDuration:[[[notification userInfo] objectForKey:UIKeyboardAnimationDurationUserInfoKey] doubleValue]];

    CGRect frame = self.view.frame;
    frame.size.height -= [[[notification userInfo] objectForKey:UIKeyboardBoundsUserInfoKey] CGRectValue].size.height;
    self.view.frame = frame;

    [UIView commitAnimations];
}

Do a similar animation for UIKeyboardWillHideNotification.