Android : Live Wallpaper, black screen

Im trying to get some frame animations working with live wallpapers, Being that I really haven't ventured beyond activities and fragments before its all a bit confusing. Following a hotchpotch of examples iv arrived at this. problem is that when i set the wallpaper, all i get is a black screen. many tanx!

 public class MainActivity extends Activity {

private Button myButton;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    myButton= (Button)findViewById(R.id.button1);


    myButton.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
        Intent i = new Intent(WallpaperManager.ACTION_CHANGE_LIVE_WALLPAPER);
        i.putExtra(WallpaperManager.EXTRA_LIVE_WALLPAPER_COMPONENT, 
                new ComponentName(MainActivity.this,Wallpaper.class));
        startActivity(i);
        }
    });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

  }


public class Wallpaper extends WallpaperService {

static final Handler myHandler = new Handler();

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

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

@Override
public Engine onCreateEngine() {
    // TODO Auto-generated method stub
    return new WallpaperSerEngine();
   }

The wallpaper engine

class WallpaperSerEngine extends Engine {
    private boolean isVisible;
    private float myScaleX;
    private float myScaleY;
    private Bitmap icon;
    private Runnable myRunnable;
    public int i = 0;
    private Bitmap mainBitmap;
    private BitmapFactory.Options myBitmapOption;
    private int index = 0;
    private long delayMillis = 90;
    int[] zone2 = { R.drawable.seven0000, R.drawable.seven0001,
            R.drawable.seven0002, R.drawable.seven0003,
            R.drawable.seven0004, R.drawable.seven0005,
            R.drawable.seven0006, R.drawable.seven0007,
            R.drawable.seven0008, R.drawable.seven0009,
            R.drawable.seven0010, R.drawable.seven0011,
            R.drawable.seven0012, R.drawable.seven0013,
            R.drawable.seven0014, R.drawable.seven0015,
            R.drawable.seven0016, R.drawable.seven0017,
            R.drawable.seven0018, R.drawable.seven0019,
            R.drawable.seven0020, R.drawable.seven0021,
            R.drawable.seven0022, R.drawable.seven0023,
            R.drawable.seven0024, R.drawable.seven0025,
            R.drawable.seven0026, R.drawable.seven0027,
            R.drawable.seven0028, R.drawable.seven0029,
            R.drawable.seven0030,

    };

    WallpaperSerEngine() {
        myRunnable = new Runnable() {
            public void run() {
                drawFrame();
            }
        };
    startMainBitmap(getResources(), zone2[0]);
    }

    private void startMainBitmap(Resources res, int resId) {
        myBitmapOption = new BitmapFactory.Options();
        myBitmapOption.inJustDecodeBounds = true;
        myBitmapOption.inMutable = true;
        BitmapFactory.decodeResource(res, resId, myBitmapOption);

        mainBitmap = Bitmap.createBitmap(myBitmapOption.outWidth,
                myBitmapOption.outHeight, Bitmap.Config.ARGB_8888);
        myBitmapOption.inJustDecodeBounds = false;
        myBitmapOption.inSampleSize = 1;
    }

    public boolean setToFrame(int frameIndex) {
        if (zone2 != null && frameIndex >= 0 && frameIndex < zone2.length) {
            index = frameIndex;
            mainBitmap = BitmapFactory.decodeResource(getResources(),
                    zone2[index], myBitmapOption);
            return true;
        } else
            return false;
    }

    @Override
    public void onCreate(SurfaceHolder surfaceHolder) {
        // TODO Auto-generated method stub
        super.onCreate(surfaceHolder);
    }

    @Override
    public void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        myHandler.removeCallbacks(myRunnable);
    }

    @Override
    public void onOffsetsChanged(float xOffset, float yOffset,
            float xOffsetStep, float yOffsetStep, int xPixelOffset,
            int yPixelOffset) {
        drawFrame();
    }

    @Override
    public void onSurfaceChanged(SurfaceHolder holder, int format,
            int width, int height) {
        // TODO Auto-generated method stub
        super.onSurfaceChanged(holder, format, width, height);
        drawFrame();
    }

    @Override
    public void onSurfaceCreated(SurfaceHolder holder) {
        // TODO Auto-generated method stub
        super.onSurfaceCreated(holder);
    }

    @Override
    public void onSurfaceDestroyed(SurfaceHolder holder) {
        // TODO Auto-generated method stub
        super.onSurfaceDestroyed(holder);
        isVisible=false;
        myHandler.removeCallbacks(myRunnable);
    }

    @Override
    public void onVisibilityChanged(boolean visible) {
        isVisible = visible;
        if (visible) {
            drawFrame();

        } else {
            myHandler.removeCallbacks(myRunnable);
        }
        // TODO Auto-generated method stub
        super.onVisibilityChanged(visible);
    }

    private void drawFrame() {
        final SurfaceHolder myHolder = getSurfaceHolder();
        Canvas myCanvas = null;
        try {
            myCanvas = myHolder.lockCanvas();
            if (myCanvas != null) {
                drawWallpaper(myCanvas);
            }

        } finally {
            if (myCanvas != null)
                myHolder.unlockCanvasAndPost(myCanvas);

        }
        myHandler.removeCallbacks(myRunnable);
        if (isVisible) {
            myHandler.postDelayed(myRunnable, delayMillis);
        }
    }

    private void drawWallpaper(Canvas c) {
        setToFrame(i);
        i++;
        if (i == 30) {
            i = 0;
        }
        Matrix myMatrix = new Matrix();
        c.scale(myScaleX, myScaleY);
        c.drawBitmap(mainBitmap, myMatrix, null);
    }

}
    }