Begins the generation of notifications of device orientation changes.
- iOS 2.0+
You must call this method before attempting to get orientation data from the receiver. This method enables the device’s accelerometer hardware and begins the delivery of acceleration events to the receiver. The receiver subsequently uses these events to post
UIDevice notifications when the device orientation changes and to update the
You may nest calls to this method safely, but you should always match each call with a corresponding call to the