Camera打开前置摄像头或后置摄像头

    private int FindFrontCamera(){  
        int cameraCount = 0;  
        Camera.CameraInfo cameraInfo = new Camera.CameraInfo();  
        cameraCount = Camera.getNumberOfCameras(); // get cameras number  
                
        for ( int camIdx = 0; camIdx < cameraCount;camIdx++ ) {  
            Camera.getCameraInfo( camIdx, cameraInfo ); // get camerainfo  
            if ( cameraInfo.facing ==Camera.CameraInfo.CAMERA_FACING_FRONT ) {   
                // 代表摄像头的方位，目前有定义值两个分别为CAMERA_FACING_FRONT前置和CAMERA_FACING_BACK后置  
               return camIdx;  
            }  
        }  
        return -1;  
    }

    private int FindBackCamera(){  
        int cameraCount = 0;  
        Camera.CameraInfo cameraInfo = new Camera.CameraInfo();  
        cameraCount = Camera.getNumberOfCameras(); // get cameras number  
                
        for ( int camIdx = 0; camIdx < cameraCount;camIdx++ ) {  
            Camera.getCameraInfo( camIdx, cameraInfo ); // get camerainfo  
            if ( cameraInfo.facing ==Camera.CameraInfo.CAMERA_FACING_BACK ) {   
                // 代表摄像头的方位，目前有定义值两个分别为CAMERA_FACING_FRONT前置和CAMERA_FACING_BACK后置  
               return camIdx;  
            }  
        }  
        return -1;  
    }  

public void surfaceCreated(SurfaceHolder holder) {  
        int CammeraIndex=FindBackCamera();  
        if(CammeraIndex==-1){  
            CammeraIndex=FindFrontCamera();  
        }  
        mCamera = Camera.open(CammeraIndex); 
　　　　 //设置预览、拍照方向
　　　　 mCamera.setDisplayOrientation(90);

}