QR code scanning--transition from horizontal screen recognition to vertical screen recognition

I participated in a competition recently and needed to implement a QR code scanning function, so I found google's open source framework Zxing, we can go to http://code.google.com/p/zxing/ to download the source code and Jar package. When I downloaded it and ran it, I found that the QR code was horizontally screened when it was recognized, and the user experience was very unpleasant, so I asked the big guys for advice on the Internet. The specific solutions are as follows:
1. In AndroidManifest.xml, modify the properties of CaptureActivity: change android:screenOrientation="landscape" to portrait
2. Find DecodeHandler.java, and modify the decode method:
   Change PlanarYUVLuminanceSource source = CameraManager.get( ).buildLuminanceSource(data, width, height); Comment out and add the following code snippet:
   byte[] newData = new byte[data.length];
        for (int y = 0; y < height; y++) {
            for (int x = 0; x < width; x++)
                newData[x * height + height - y - 1] = data[x + y * width];
        }
        int tmp = width;
        width = height;
        height = tmp;

        PlanarYUVLuminanceSource source = CameraManager.get().buildLuminanceSource(newData, width, height);
3、找到CameraManager.java，修改其中的getFramingRectInPreview方法：
   注释掉rect.left = rect.left * cameraResolution.x / screenResolution.x;
   rect.right = rect.right * cameraResolution.x / screenResolution.x;
   rect.top = rect.top * cameraResolution.y / screenResolution.y;
   rect.bottom = rect.bottom * cameraResolution.y / screenResolution.y;
   并添加rect.left = rect.left * cameraResolution.y / screenResolution.x;
   rect.right = rect.right * cameraResolution.y / screenResolution.x;
   rect.top = rect.top * cameraResolution.x / screenResolution.y;
   rect.bottom = rect.bottom * cameraResolution.x / screenResolution.y;
4. Find CameraConfigurationManager.java and modify the initFromCameraParameters method:
   add the code at the end Point screenResolutionForCamera =new Point();
        screenResolutionForCamera.x = screenResolution.x;
        screenResolutionForCamera.y = screenResolution.y;
        if (screenResolution.x < screenResolution.y ) {
            screenResolutionForCamera.x = screenResolution.y;
            screenResolutionForCamera.y = screenResolution.x;
        }
        cameraResolution = getCameraResolution(parameters, screenResolutionForCamera);
5. Same as the above class, modify the method setDesiredCameraParameters method:
   add code at the end
   // make Rotate the camera by 90 degrees
   setDisplayOrientation(camera, 90);
   and write a method code as follows:
   /*Method to change the direction of camera imaging*/
    protected void setDisplayOrientation(Camera camera, int angle) {
        Method downPolymorphic = null;
        try {
            downPolymorphic = camera.getClass().getMethod("setDisplayOrientation", new Class[] { int.class });
            if (downPolymorphic != null)
                downPolymorphic.invoke(camera, new Object[]{angle});
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (IllegalArgumentException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        }
    }
At this point, the modification has ended, and the pro-test is valid.

Reference article: http://blog.csdn.net/chenbin520/article/details/16362459
http://407827531.iteye.com/blog/1488676