Android下利用zxing类库实现扫一扫

 public void onPreviewFrame(byte[] data, Camera camera) 
  {
    Point cameraResolution = configManager.getCameraResolution();
    if (!useOneShotPreviewCallback) 
    {
      camera.setPreviewCallback(null);
    }
    if (previewHandler != null) 
    {
      Message message = previewHandler.obtainMessage(previewMessage, cameraResolution.x,cameraResolution.y, data);
      message.sendToTarget();
      previewHandler = null;
    } 
    else 
    {
      Log.d(TAG, "Got preview callback, but no handler for it");
    }
  }

private void decode(byte[] data, int width, int height)
  {
    long start = System.currentTimeMillis();
    Result rawResult = null;
    
    byte[] rotatedData = new byte[data.length];
    for (int y = 0; y < height; y++) {
        for (int x = 0; x < width; x++)
            rotatedData[x * height + height - y - 1] = data[x + y * width];
    }
    int tmp = width; // Here we are swapping, that‘s the difference to #11
    width = height;
    height = tmp;
    
    PlanarYUVLuminanceSource source = CameraManager.get().buildLuminanceSource(rotatedData, width, height);
    BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));
    try 
    {
      rawResult = multiFormatReader.decodeWithState(bitmap);
    } catch (ReaderException re) {
      // continue
    } finally {
      multiFormatReader.reset();
    }

    if (rawResult != null) 
    {
      long end = System.currentTimeMillis();
      Log.d(TAG, "Found barcode (" + (end - start) + " ms):\n" + rawResult.toString());
      Message message = Message.obtain(activity.getHandler(), R.id.decode_succeeded, rawResult);
      Log.d(TAG, "Sending decode succeeded message...");
      message.sendToTarget();
    } 
    else 
    {
      Message message = Message.obtain(activity.getHandler(), R.id.decode_failed);
      message.sendToTarget();
    }
  }