Android Camera 打开预览流程分析（三）-- Camera 连接到CameraService 过程分析

上篇已经分析了CameraService 的初始化过程，之前分析到ICameraService.connectDevice(…), 通过CameraService建立起cameraID 与CameraDevice的联系，那我们继续往下分析， CameraPreview创建的过程：

   private void createCameraPreviewSession() {
   
        try {
   
            SurfaceTexture texture = mTextureView.getSurfaceTexture();
            assert texture != null;

            // We configure the size of default buffer to be the size of camera preview we want.
            texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());

            // This is the output Surface we need to start preview.
            //初始化一个surface,当成一个preview的一个buffer数据
            Surface surface = new Surface(texture);

            // We set up a CaptureRequest.Builder with the output Surface.
            mPreviewRequestBuilder
                    = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
            mPreviewRequestBuilder.addTarget(surface);

            // Here, we create a CameraCaptureSession for camera preview.
            //把surface 和 mImageReader的buffer 当成preview的一个surface 的集合
            mCameraDevice.createCaptureSession(Arrays.asList(surface, mImageReader.getSurface()),
                    new CameraCaptureSession.StateCallback() {
   
                    ...
                    }
             }

    public void createCaptureSession(List<Surface> outputs,
            CameraCaptureSession.StateCallback callback, Handler handler)
            throws CameraAccessException {
   
        List<OutputConfiguration> outConfigurations = new ArrayList<>(outputs.size());
        //将之前的surface集合 转化成OutputConfiguration的集合
        for (Surface surface : outputs) {
   
            outConfigurations.add(new OutputConfiguration(surface));
        }
        //根据OutputConfiguration集合， 再来创建captureSession
        createCaptureSessionInternal(null, outConfigurations, callback,
                checkAndWrapHandler(handler), /*operatingMode*/ICameraDeviceUser.NORMAL_MODE,
                /*sessionParams*/ null);
    }

    private void createCaptureSessionInternal(InputConfiguration inputConfig,
            List<OutputConfiguration>