iOS-Keyboard

After 3 years of iOS development practice, finally I have chance to fully work with the soft keyboard. I found the Apple official docs is far from enough to deal with every cases of iOS soft keyboard. Then online 3rd party docs are helpful but not complete either. I can understand it since everyone is busy, very few people to write a complete guide for any specific topics. 

Then I come to this. I have to do trial and error to grasp this piece of knowledge. One problem I was facing is when device is in landscape, you cannot use keyboard's height to adjust textview/tableview's contentInsets, since the height actually seems as its "width". UIWindow is mounted always in portrait mode, and keyboard frame goes with it. When device and UI is in landscape, the keyboard frame is still measured as it is in portrait. The solution:

    CGRect frameEnd = [[notif.userInfo objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue];
    frameEnd = [self.view convertRect: frameEnd fromView: nil];