How to get event or notification of the input method changing?(IOS5.1)

Question

(In IOS 5.1 Xcode 4.3) When the user clicked the button to switch keyboard input method, how to get to this event and to determine the state of the input method?

Answer 1

When the input method changes, although the keyboard is already there, iOS will send the UIKeyboardDidShowNotification. You can register yourself for this notification like:

[[NSNotificationCenter defaultCenter] addObserver:self 
                                     selector:@selector(keyboardDidShow:) 
                                         name:UIKeyboardDidShowNotification
                                       object:nil];

Thats actually all you can do from my point of view! I'm not sure if it's possible to detect the current input method of the keyboard directly! Or maybte take a look at the following discussion: Detecting current iPhone input language!