Android: Trouble Rotating a bitmap on orientation sensor Y axis (pitch)

Question

Hello i am in desperate need of help on this i have an image of a steering and i want to rotate it when the phone is tilted left or right. My app is in landscape mode. You should see the code below. The problem is that the bitmap does not rotate and redraws on different position. I am unable to find the problem.

public class Accelerometer extends Activity {

 mySteering steering = null;
 private static SensorManager mySensorManager;
 private boolean sensorrunning;
 public  float y;

   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);

       steering = new mySteering(this);

       setContentView(steering);

       mySensorManager = (SensorManager)getSystemService(Context.SENSOR_SERVICE);
       List<Sensor> mySensors = mySensorManager.getSensorList(Sensor.TYPE_ORIENTATION);

       if(mySensors.size() > 0){
        mySensorManager.registerListener(mySensorEventListener, mySensors.get(0), SensorManager.SENSOR_DELAY_NORMAL);
        sensorrunning = true;
        Toast.makeText(this, "Start ORIENTATION Sensor", Toast.LENGTH_LONG).show();
       }
       else{
        Toast.makeText(this, "No ORIENTATION Sensor", Toast.LENGTH_LONG).show();
        sensorrunning = false;
        finish();
       }

   }

   private SensorEventListener mySensorEventListener = new SensorEventListener() {

  @Override
  public void onSensorChanged(SensorEvent event) {
   // TODO Auto-generated method stub


   y = event.values[1];
  }

  @Override
  public void onAccuracyChanged(Sensor sensor, int accuracy) {
   // TODO Auto-generated method stub

  }
 };

 @Override
 protected void onDestroy() {
  // TODO Auto-generated method stub
  super.onDestroy();

  if(sensorrunning){
   mySensorManager.unregisterListener(mySensorEventListener);
   Toast.makeText(Accelerometer.this, "unregisterListener", Toast.LENGTH_SHORT).show();
  }
 }

@Override
protected void onStart() {
    // TODO Auto-generated method stub
    super.onStart();
}

public class mySteering extends View {
    static final int width = 50;
    static final int height = 50;

    Accelerometer sensor = new Accelerometer();
    Matrix rot = new Matrix();

    public mySteering(Context context) {
        super(context);

    }

    protected void onDraw(Canvas canvas) {

        Bitmap bmp = BitmapFactory.decodeResource(getResources(),
                R.drawable.steering);
        Paint p = new Paint(); // set some paint options
        p.setColor(Color.WHITE);

        int canvasWidth = canvas.getWidth();
        int canvasHeight = canvas.getHeight();
        int centreX = (canvasWidth) / 2;

        int centreY = (canvasHeight) / 2;

        canvas.drawText("This is on Y   " + sensor.y, 5, 40, p);



        if (sensor.y <= 12.0 && sensor.y >= -12.0) {


             canvas.drawBitmap(bmp, centreX, centreY, null);
             invalidate();
             }  

        if (sensor.y > 20.0 && sensor.y < 0.0) {

         rot.setRotate(45, centreX, centreY);
         canvas.drawBitmap(bmp, rot, p);
         invalidate();
         } 



         if (sensor.y < -20.0 && sensor.y > 0.0 ) {
             rot.setRotate(-45, centreX, centreY);
             canvas.drawBitmap(bmp, rot, p);
             invalidate();
         }

Can some one figure out or alter the mistakes in the code? Thanks in advance. This is how it looks this time is not rotating or not even redrawn.

screenshot

set the steering.sensor from your public void onAccuracyChanged(Sensor sensor, int accuracy) method with parameter sensor, and invalidate the steering there. — Sudar Nimalan, Jun 18 '12 at 09:05

Sudar Nimalan · Accepted Answer · 2012-06-19T08:56:05.590

0

you may have to pass the sensor value as follows:

 public void onSensorChanged(SensorEvent event) {
   // TODO Auto-generated method stub

   steering.sensor = this;
   y = event.values[1];
   steering.invalidate();
  }

edited Jun 19 '12 at 08:56

answered Jun 19 '12 at 01:36

Sudar Nimalan

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Type mismatch: cannot convert from new SensorEventListener(){} to Accelerometer – user1422066 Jun 20 '12 at 08:08
please try this:- steering.sensor = Accelerometer.this; – Sudar Nimalan Jun 20 '12 at 08:10
thanks it works but the other problem still remains when the wheel rotates to the given angle on the if statements it redraws on different locations. What is the way to rotate the bitmap at the same position without the look and feel that it is drawing again and again ? – user1422066 Jun 20 '12 at 13:00
the problem i see is my centreX and centerY keep on changing when rotating how should i fix them and draw the bitmap on the center of the screen regardless of the sensor? – user1422066 Jun 20 '12 at 18:50

Android: Trouble Rotating a bitmap on orientation sensor Y axis (pitch)

1 Answers1