1. 在布局文件中添加一个预览窗口和一个拍照按钮

2. 在活动类中创建预览管理器和摄像头实例

private Camera mCamera; private CameraPreview mPreview;

// Create an instance of Camera mCamera = getCameraInstance();

// Create our Preview view and set it as the content of our activity. mPreview = new CameraPreview(this, mCamera); FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview); preview.addView(mPreview);

// get an instance of the Camera object public static Camera getCameraInstance(){ Camera c = null; try { c = Camera.open(); // attempt to get a Camera instance } catch (Exception e){ // Camera is not available (in use or does not exist) } return c; // returns null if camera is unavailable }

3. 在预览管理器类中创建PreviewCallback以对预览帧进行处理

private SurfaceHolder mHolder;

private class CameraPreview extends SurfaceView implements SurfaceHolder.Callback { private Camera mCamera; private PreviewCallback mPreviewCallback = new PreviewCallback() { public void onPreviewFrame(byte[] data, Camera camera) { // Process the preview image } };

public CameraPreview(Context context, Camera camera) {
    super(context);
    mCamera = camera;
    mHolder = getHolder();
    mHolder.addCallback(this);
}

public void surfaceCreated(SurfaceHolder holder) {
    // Start the preview
    try {
        mCamera.setPreviewDisplay(holder);
        mCamera.setPreviewCallback(mPreviewCallback);
        mCamera.startPreview();
    } catch (IOException e) {
        Log.d(TAG, "Error setting camera preview: " + e.getMessage());
    }
}

public void surfaceDestroyed(SurfaceHolder holder) {
    // Release the camera
    mCamera.stopPreview();
    mHolder.removeCallback(this);
    mCamera.release();
    mCamera = null;
}

public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
    // Adjust the preview layout
    if (mHolder.getSurface() == null){
        // preview surface does not exist
        return;
    }
    // stop preview before making changes