CupertinoContextMenu ios弹出菜单

一个华丽的iOS风格按钮弹出框，长按时会以动画的形式弹出菜单面板，通常和CupertinoContextMenuAction联用。

相关组件

CupertinoContextMenuAction

CupertinoContextMenu基本使用

   <br />【child】 : 子组件   【Widget】<br />【actions】 : 行为组件集   【List<Widget>】<br />【previewBuilder】 : 动画构造器  【ContextMenuPreviewBuilder】<br />![72.gif](https://cdn.nlark.com/yuque/0/2020/gif/326147/1589444346675-19bbae42-d362-4564-9467-5166b8042b07.gif#align=left&display=inline&height=590&margin=%5Bobject%20Object%5D&name=72.gif&originHeight=590&originWidth=404&size=2139876&status=done&style=none&width=404)

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
class CustomCupertinoContextMenu extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Container(
      child: _buildCupertinoContextMenu(context),
    );
  }

  final info= ['保存图片','立刻呼叫','添加到收藏夹'];

  Widget _buildCupertinoContextMenu(context) => Container(
    decoration: BoxDecoration(
        image: DecorationImage(
            image: AssetImage('assets/images/sabar_bar.jpg'),
            fit: BoxFit.cover),
        borderRadius: BorderRadius.all(Radius.circular(50))),
    width: 100,
    height: 100,
    child: CupertinoContextMenu(
          child: Container(
            decoration: BoxDecoration(
                image: DecorationImage(
                    image: AssetImage('assets/images/sabar_bar.jpg'),
                    fit: BoxFit.cover),
                borderRadius: BorderRadius.all(Radius.circular(50))),
          ),
          actions: info.map((e)=>CupertinoContextMenuAction(
            child: Center(child: Text(e)),
            onPressed: () => Navigator.pop(context),
          )).toList())
  );
}