在flutter中使用video_player插件时，如何显示当前视频的播放时间？

import 'package:video_player/video_player.dart';

VideoPlayerController _controller;

@override
void initState() {
  super.initState();
  _controller = VideoPlayerController.asset('assets/video.mp4')
    ..initialize().then((_) {
      setState(() {});
    });
}

Widget build(BuildContext context) {
  return Scaffold(
    appBar: AppBar(
      title: Text('Video Player'),
    ),
    body: Center(
      child: _controller.value.initialized
          ? AspectRatio(
              aspectRatio: _controller.value.aspectRatio,
              child: VideoPlayer(_controller),
            )
          : CircularProgressIndicator(),
    ),
  );
}

Text(
  '${_controller.value.position.inMinutes}:${(_controller.value.position.inSeconds % 60).toString().padLeft(2, '0')}',
  style: TextStyle(fontSize: 20),
)