I\'m developing an android application, and I have a button which starts/pauses certain simulation process. While this process is running, I need to output some data from it
You can handle it in many ways,
Try to use AsyncTask in this, your background work done in doInBackGround() method, and your UI will not block and you can also access the views of Activity from where you call AsyncTask by its context via publishProgress() and onProgressUpdate() .
If you are using a simple Thread then using Handler or message or runOnUiThread you can update the view of main thread.
but, in your way I think AsyncTask is best for you.