How to get Notification whether Keyboard is showing or not in iOS

//Get Notification whether Keyboard is showing or not
 [self registerForKeyboardNotifications];

#pragma mark - Notify Keyboard is Showing / Hiding
 - (void)registerForKeyboardNotifications
 {
 // Call this method somewhere in your view controller setup code.
 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWasShown:) name:UIKeyboardDidShowNotification object:nil];
  
 [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillBeHidden:) name:UIKeyboardWillHideNotification object:nil];
  
 }

#pragma mark - Handle Keyboard Notification

- (void)keyboardWasShown:(NSNotification*)aNotification
 {
 // Called when the UIKeyboardDidShowNotification is sent.
 //Create Animation Block for UIView

//NSDictionary* info = [aNotification userInfo];
 //CGRect beginFrame = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue];
 //CGRect endFrame = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
 //DebugLog(@"beginFrame %f",beginFrame.size.height);
 //DebugLog(@"endFrame %f",endFrame.size.height);
 }
 - (void)keyboardWillBeHidden:(NSNotification*)aNotification
 {
 // Called when the UIKeyboardWillHideNotification is sent
 }