hyzp_ybqx/lib/my_flutter_drag_scale/example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter_drag_scale/flutter_drag_scale.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      height: 400.0,
      width: 400,
      child: Center(
        child: DragScaleContainer(
          doubleTapStillScale: true,
          child: new Image(
            image: new NetworkImage(
                'http://h.hiphotos.baidu.com/zhidao/wh%3D450%2C600/sign=0d023672312ac65c67506e77cec29e27/9f2f070828381f30dea167bbad014c086e06f06c.jpg'),
          ),
        ),
      ),
    );
  }
}