Upvote:2

Aprove answer 
- (void)keyboardWillShow: (NSNotification *) notif
    {
    keyH = [notif.userInfo[UIKeyboardFrameEndUserInfoKey] CGRectValue].size.height ;
    NSString *javascriptString ;
    javascriptString = [NSString stringWithFormat:@"IOSKeyboardChanged(%d)",keyH];
    [webView evaluateJavaScript:javascriptString completionHandler:nil];
    }

- (void)keyboardWillHide: (NSNotification *) notif
    {
    [webView evaluateJavaScript:@"IOSKeyboardChanged(0)" completionHandler:nil];
    }

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