How to get UIKeyboard size with iOS

Tharindu Madushanka picture Tharindu Madushanka · Aug 23, 2010 · Viewed 85.7k times · Source

Is there some way to get UIKeyboard size programmatically. 216.0f height and 162.0f height in landscape.

Following seem to be deprecated. Is there some way that works without any warning in both 3.0 iPhone OS SDK and 4.0 iPhone OS SDK to do this..

CGSize keyBoardSize = [[[note userInfo]
                        objectForKey:UIKeyboardBoundsUserInfoKey] CGRectValue].size;

Answer

James Bedford picture James Bedford · Mar 16, 2011

You can get the keyboard size from the userInfo dictionary using the UIKeyboardFrameBeginUserInfoKey and the UIKeyboardFrameEndUserInfoKey instead.

These two keys return a NSValue instance containing a CGRect that holds the position and size of the keyboard at both the start and end points of the keyboard's show/hide animation.

Edit:

To clarify, the userInfo dictionary comes from an NSNotification instance. It's passed to your method that you register with an observer. For example,

- (void)someMethodWhereYouSetUpYourObserver
{
    // This could be in an init method.
    [[NSNotificationCenter defaultCenter] addObserver:self 
                    selector:@selector(myNotificationMethod:) 
                    name:UIKeyboardDidShowNotification 
                    object:nil];
}

- (void)myNotificationMethod:(NSNotification*)notification
{
    NSDictionary* keyboardInfo = [notification userInfo];
    NSValue* keyboardFrameBegin = [keyboardInfo valueForKey:UIKeyboardFrameBeginUserInfoKey];
    CGRect keyboardFrameBeginRect = [keyboardFrameBegin CGRectValue];
}

Edit 2:

Also, please don't forget to remove yourself as an observer in your dealloc method! This is to avoid a crash that would occur when the notification center tries to notify your object after its been freed.