I am trying to follow the instructions on this page to create a trace file. I can see the file in File Explorer in DDMS and can pull it onto my PC but it is zero bytes long.
Any suggestions as to what I might be doing wrong, please?
The problem seems to have been that the stopMethodTracing() call which I had put in the onDestroy() method (as suggested in the Dev Guide) failed to stop the tracing even though I had tried three different means of ending the activity ... rotating the screen, pressing the Home Key and using Taskiller to kill the app.
By moving the stopMethodTracing() elsewhere I now have a trace with data in it!
(The vital clue was that I noticed that LogCat was reporting TRACE STARTED but never reported TRACE STOPPED.)
来源：https://stackoverflow.com/questions/2180387/android-trace-file-created-but-zero-bytes-long