CameraManager.java 文件源码

/**
 * Like {@link #getFramingRect} but coordinates are in terms of the preview frame,
 * not UI / screen.
 *
 * @return {@link Rect} expressing barcode scan area in terms of the preview size
 */
public synchronized Rect getFramingRectInPreview() {
    if (framingRectInPreview == null) {
        Rect framingRect = getFramingRect();
        if (framingRect == null) {
            return null;
        }
        Rect rect = new Rect(framingRect);
        Point cameraResolution = configManager.getCameraResolution();
        Point screenResolution = configManager.getScreenResolution();
        if (cameraResolution == null || screenResolution == null) {
            // Called early, before init even finished
            return null;
        }

        if (view.getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
            rect.left = rect.left * cameraResolution.y / screenResolution.x;
            rect.right = rect.right * cameraResolution.y / screenResolution.x;
            rect.top = rect.top * cameraResolution.x / screenResolution.y;
            rect.bottom = rect.bottom * cameraResolution.x / screenResolution.y;
        } else {
            rect.left = rect.left * cameraResolution.x / screenResolution.x;
            rect.right = rect.right * cameraResolution.x / screenResolution.x;
            rect.top = rect.top * cameraResolution.y / screenResolution.y;
            rect.bottom = rect.bottom * cameraResolution.y / screenResolution.y;
        }

        framingRectInPreview = rect;
    }
    return framingRectInPreview;
}