close camera application in blackberry

Question

I need to close camera when a file is taken from camera. I invoke camera by Invoke method and added FileJournalListener and then use Inject.post. But it si working fine in simulator and but not working in actual device. any Idea.

....... case FileSystemJournalEntry.FILE_ADDED:

                    filepath=path;

                     EventInjector.KeyEvent inject = new EventInjector.KeyEvent(EventInjector.KeyEvent.KEY_DOWN,Characters.ESCAPE,  50);
                     inject.post();
                     inject.post();

............