相关疑难解决方法(0)

因此，我需要叠加camera2预览，并通过在顶部叠加透明叠加，在预览视频图像上绘制一个矩形。我从这里的基本Camera2代码开始：https：//github.com/googlesamples/android-Camera2Basic

上面使用TextureView进行相机预览。

接下来，我将以下类添加到项目中

private class CustomView extends SurfaceView {

    private final Paint paint;
    private final SurfaceHolder mHolder;
    private final Context context;

    public CustomView(Camera2BasicFragment context) {
        super(context.getActivity().getBaseContext());
        mHolder = getHolder();
        mHolder.setFormat(PixelFormat.TRANSPARENT);
        this.context = context.getActivity().getBaseContext();
        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        paint.setColor(Color.WHITE);
        paint.setStyle(Paint.Style.STROKE);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            invalidate();
            if (mHolder.getSurface().isValid()) {
                final Canvas canvas = mHolder.lockCanvas();
                Log.d("touch", "touchRecieved by camera");
                if (canvas != null) { …