android Camera 如何判断当前使用的摄像头是前置还是后置

 1 /** 
 2  * Information about a camera 
 3  */  
 4 public static class CameraInfo {  
 5     /** 
 6      * The facing of the camera is opposite to that of the screen. 
 7      */  
 8     public static final int CAMERA_FACING_BACK = 0;  
 9   
10     /** 
11      * The facing of the camera is the same as that of the screen. 
12      */  
13     public static final int CAMERA_FACING_FRONT = 1;  
14   
15     /** 
16      * The direction that the camera faces. It should be 
17      * CAMERA_FACING_BACK or CAMERA_FACING_FRONT. 
18      */  
19     public int facing;  
20   
21     /** 
22      * <p>The orientation of the camera image. The value is the angle that the 
23      * camera image needs to be rotated clockwise so it shows correctly on 
24      * the display in its natural orientation. It should be 0, 90, 180, or 270.</p> 
25      * 
26      * <p>For example, suppose a device has a naturally tall screen. The 
27      * back-facing camera sensor is mounted in landscape. You are looking at 
28      * the screen. If the top side of the camera sensor is aligned with the 
29      * right edge of the screen in natural orientation, the value should be 
30      * 90. If the top side of a front-facing camera sensor is aligned with 
31      * the right of the screen, the value should be 270.</p> 
32      * 
33      * @see #setDisplayOrientation(int) 
34      * @see Parameters#setRotation(int) 
35      * @see Parameters#setPreviewSize(int, int) 
36      * @see Parameters#setPictureSize(int, int) 
37      * @see Parameters#setJpegThumbnailSize(int, int) 
38      */  
39     public int orientation;  
40 };  

1 Camera.CameraInfo info = new Camera.CameraInfo();  
2 Camera.getCameraInfo(cameraId, info); 

1 CameraInfo info = CameraHolder.instance().getCameraInfo()[mCameraId];  
2 if (info.facing == CameraInfo.CAMERA_FACING_FRONT) {  
3     //stopFaceDetection();  
4 }