二维码扫描（横屏、竖屏、解决竖屏后拉伸问题、美化扫描框）

以前上传过一个源码：Android二维码扫描简单源码

是根据zxing的源码进行简化的，不过只支持横屏。

其实支持竖屏也挺简单的：【http://stackoverflow.com/questions/16252791/zxing-camera-in-portrait-mode-on-android】

Step 1: Add following lines to rotate data before buildLuminanceSource(..) in decode(byte[] data, int width, int height)

DecodeHandler.java:

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;
width = height;
height = tmp;

PlanarYUVLuminanceSource source = activity.getCameraManager().buildLuminanceSource(rotatedData, width, height);

---

Step 2: Modify getFramingRectInPreview().

CameraManager.java

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;

---

Step 3: Disable the check for Landscape Mode in initFromCameraParameters(...)

CameraConfigurationManager.java

//remove the following
if (width < height) {
  Log.i(TAG, "Display reports portrait orientation; assuming this is incorrect");
  int temp = width;
  width = height;
  height = temp;
}

---

Step 4: Add following line to rotate camera insetDesiredCameraParameters(...)

CameraConfigurationManager.java

camera.setDisplayOrientation(90);

---

Step 5: Do not forget to set orientation of activity to portrait. I.e: manifest

但是这样之后，会出现拉伸的问题，解决方法如下：

更改CameraConfigurationManager.java文件

在 Log.d(TAG, "Screen resolution: " + screenResolution);这句之后增加
Point screenResolutionForCamera = new Point();
        screenResolutionForCamera.x = screenResolution.x;
        screenResolutionForCamera.y = screenResolution.y;
        // preview size is always something like 480*320, other 320*480
        if (screenResolution.x < screenResolution.y) {
        screenResolutionForCamera.x = screenResolution.y;
        screenResolutionForCamera.y = screenResolution.x;
        }
再更改cameraResolution = getCameraResolution(parameters, screenResolution);为cameraResolution = getCameraResolution(parameters, screenResolutionForCamera);

如果想美化一下取景框，可以参看代码：https://code.csdn.net/snippets/64838