StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

POCall SensorManager from AsyncTask?
text
Body
copied!<p>How do I call the SensorManager from inside -</p> <pre><code>protected String doInBackground(String... params) { ..... } </code></pre> <p>I have to log the acclerometer data on to a file. This application runs in the background. Hence I am using AsyncTask to implement it. I need to start and stop the logging by pressing the button (onClick). Any pointers would be helpful!!</p> <p>This is the update... The file written is empty...How do I start the logging?</p> <pre><code>public class AsyncTaskActivity extends Activity implements SensorEventListener{ Button btn; File root = Environment.getExternalStorageDirectory(); StringBuilder builder = new StringBuilder(); File gpxfile = new File(root, "TestFile.txt"); String fileText = "Data"; FileWriter gpxwriter; BufferedWriter out; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); btn = (Button) findViewById(R.id.button1); btn.setOnClickListener(new OnClickListener() { public void onClick(View v) { new LongOperation(new AsyncTaskActivity()).execute(""); } }); } private class LongOperation extends AsyncTask<String, Void, String> { private AsyncTaskActivity mActivity; public LongOperation (AsyncTaskActivity activity) { mActivity = activity; } @Override protected String doInBackground(String... params) { try { gpxwriter = new FileWriter(gpxfile); out = new BufferedWriter(gpxwriter); if (root.canWrite()){ SensorManager manager = (SensorManager) mActivity.getSystemService(Context.SENSOR_SERVICE); Sensor accelerometer = manager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER); if(!manager.registerListener((SensorEventListener) this, accelerometer, SensorManager.SENSOR_DELAY_GAME)){ System.out.println("Could not start!!!!!!!!!"); } out.write("Start"); out.newLine(); out.close(); } } catch (IOException e) { Log.e("doIn","Could not write file " + e.getMessage()); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } @Override protected void onPostExecute(String result) { TextView txt = (TextView) findViewById(R.id.output); txt.setText("File written successfully!!!"); } @Override protected void onPreExecute() { } @Override protected void onProgressUpdate(Void... values) { } } @Override public void onAccuracyChanged(Sensor sensor, int accuracy) { // TODO Auto-generated method stub } @Override public void onSensorChanged(SensorEvent event) { // TODO Auto-generated method stub builder.setLength(0); builder.append(event.values[0]+","+event.values[1]+","+event.values[2]); try { out.append(builder.toString()); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } </code></pre>

Querying!

Guidance

An individual column

Larger individual text columns get their own page to allow for proper reading.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload