GraphView Uhrzeit als x-Achse

Hi,
ich habe eine Problem mit der GraphView. Ich lade aus einer SQL-Datenbank Werte. Einen int-wert für die y-Achse und einen String für die Uhrzeit als HH:mm:ss.SSS. Wenn ich nun den String in ein Date-Objekt umwandle und mir in der x-Achse anzeigen lasse, bekomme ich immer den 01.01.70. Ich will eben kein Datum, sondern nur die Uhrzeit.

Hat jemand eine Idee wie ich das ändern kann?

 @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    requestWindowFeature(Window.FEATURE_NO_TITLE);
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
            WindowManager.LayoutParams.FLAG_FULLSCREEN);
    setContentView(R.layout.activity_messung);

    Button button_restart_activity = (Button) findViewById(R.id.button_refresh);
    button_restart_activity.setOnClickListener(this);

    graph = (GraphView) findViewById(R.id.graph);

    series.setDrawDataPoints(true);
    /*
    series = new LineGraphSeries<>(new DataPoint[] {
            new DataPoint(0, 0)
    });
       */

    // set manual X bounds
    graph.getViewport().setYAxisBoundsManual(true);
    graph.getViewport().setMinY(0);
    graph.getViewport().setMaxY(1500);

    timeNow = Calendar.getInstance();
    //format.format(timeNow.getTime());

    graph.getViewport().setXAxisBoundsManual(true);
    graph.getViewport().setMinX(0);
    graph.getViewport().setMaxX(0.1);

    // enable scaling and scrolling
    graph.getViewport().setScalable(true);
    graph.getViewport().setScalableY(true);

    graph.getViewport().setScrollable(true);
    graph.getViewport().setScrollableY(true);

    //graph.getGridLabelRenderer().setHorizontalAxisTitle("Zeit");
    graph.getGridLabelRenderer().setVerticalAxisTitle("Paketlänge");

    graph.getLegendRenderer().setVisible(true);
    graph.getLegendRenderer().setWidth(375);
    graph.getLegendRenderer().setMargin(60);

    graph.getLegendRenderer().setAlign(LegendRenderer.LegendAlign.TOP);
    // set date label formatter
    graph.getGridLabelRenderer().setLabelFormatter(new DateAsXAxisLabelFormatter(getApplicationContext()));
    graph.getGridLabelRenderer().setNumHorizontalLabels(3); // only 4 because of the space

    graph.getGridLabelRenderer().setHumanRounding(false);





    Timer t1 = new Timer();

    t1.schedule(new TimerTask() {

            @Override
            public void run() {
                getData();
                               }

        }, 0, 1500); //alle 1,5 Sekunden...

}


protected void addPoints() {
    try {
        JSONObject jsonObj = new JSONObject(myJSON);
        werte = jsonObj.getJSONArray(TAG_RESULTS);

        //Gibt Resourcen frei
        graph.removeSeries(series);

        for (int i = 0; i < werte.length(); i++) {
            JSONObject c = werte.getJSONObject(i);

            int id = c.getInt(TAG_ID);
            String zeit = c.getString(TAG_ZEIT);
            String typ = c.getString(TAG_TYP);
            int laenge = c.getInt(TAG_LAENGE);

            try {
                xIntRaw.setTime(format.parse(zeit));// all done
            }catch(ParseException e){
                e.printStackTrace();
            }
            //long xInt = ((xIntRaw.getTimeInMillis()/10)-(timeNow.getTimeInMillis()/10));

            Date xInt = xIntRaw.getTime();






            int yInt = laenge;

            points.add(new DataPoint(xInt,yInt));

        }

            dbPoint = points.toArray(new DataPoint[points.size()]);

            series = new LineGraphSeries<>(dbPoint);

            graph.addSeries(series);

            series.setTitle("Paketlänge/Zeit");

    } catch (JSONException e) {
        e.printStackTrace();
    }

}


public void getData() {
    class GetDataJSON extends AsyncTask<String, Void, String> {

        @Override
        protected String doInBackground(String... params) {
            DefaultHttpClient httpclient = new DefaultHttpClient(new BasicHttpParams());
            //HttpPost httppost = new HttpPost("http://10.10.0.1/getter.php");
            HttpPost httppost = new HttpPost("http://s466958426.online.de/basti/getter1.php");

            // Depends on your web service
            httppost.setHeader("Content-type", "application/json");

            InputStream inputStream = null;
            String result = null;
            try {
                HttpResponse response = httpclient.execute(httppost);
                HttpEntity entity = response.getEntity();

                inputStream = entity.getContent();
                // json is UTF-8 by default
                BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream, "UTF-8"), 8);
                StringBuilder sb = new StringBuilder();

                String line = null;
                while ((line = reader.readLine()) != null) {
                    sb.append(line + "\n");
                }
                result = sb.toString();
            } catch (Exception e) {
                // Oops
            } finally {
                try {
                    if (inputStream != null) inputStream.close();
                } catch (Exception squish) {
                }
            }
            return result;
        }

        @Override
        protected void onPostExecute(String result) {
            myJSON = result;
            addPoints();
        }
    }
    GetDataJSON g = new GetDataJSON();
    g.execute();
}

Viele Grüße Basti