二维码扫描--横屏识别转为竖屏识别

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最近在参加一次比赛，需要实现一个二维码扫描的功能，于是找到了google的开源框架Zxing,我们可以去http://code.google.com/p/zxing/下载源码和Jar包。下载下来运行时发现二维码在识别时是横屏的，用户体验很不爽，于是在网上求教大佬们支招。具体解决方法如下：
1、在AndroidManifest.xml中，修改CaptureActivity的属性：将android:screenOrientation="landscape"改为portrait
2、找到DecodeHandler.java，修改其中的decode方法：
   将PlanarYUVLuminanceSource source = CameraManager.get().buildLuminanceSource(data, width, height);注释掉，并添加下面代码段：
   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、找到CameraConfigurationManager.java，修改其中的initFromCameraParameters方法：
   在最后添加代码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、同样是上面的类，修改其中的方法setDesiredCameraParameters方法：
   在最后添加代码
   // 使摄像头旋转90度
   setDisplayOrientation(camera, 90);
   并写一个方法代码如下：
   /*改变照相机成像的方向的方法*/
    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();
        }
    }
至此修改已经结束，亲测有效。

参考文章：http://blog.csdn.net/chenbin520/article/details/16362459
http://407827531.iteye.com/blog/1488676