AppFlowy/frontend/appflowy_flutter/packages/appflowy_popover/example/lib/main.dart

import 'package:appflowy_popover/appflowy_popover.dart';
import 'package:flutter/material.dart';
import "./example_button.dart";

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        // This is the theme of your application.
        //
        // Try running your application with "flutter run". You'll see the
        // application has a blue toolbar. Then, without quitting the app, try
        // changing the primarySwatch below to Colors.green and then invoke
        // "hot reload" (press "r" in the console where you ran "flutter run",
        // or simply save your changes to "hot reload" in a Flutter IDE).
        // Notice that the counter didn't reset back to zero; the application
        // is not restarted.
        primarySwatch: Colors.blue,
      ),
      home: const MyHomePage(title: 'AppFlowy Popover Example'),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({Key? key, required this.title}) : super(key: key);

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Row(children: [
        Column(children: [
          const ExampleButton(
            label: "Left top",
            offset: Offset(0, 10),
            direction: PopoverDirection.bottomWithLeftAligned,
          ),
          Expanded(child: Container()),
          const ExampleButton(
            label: "Left bottom",
            offset: Offset(0, -10),
            direction: PopoverDirection.topWithLeftAligned,
          ),
        ]),
        Expanded(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              const ExampleButton(
                label: "Top",
                offset: Offset(0, 10),
                direction: PopoverDirection.bottomWithCenterAligned,
              ),
              Expanded(
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  crossAxisAlignment: CrossAxisAlignment.center,
                  children: const [
                    ExampleButton(
                      label: "Central",
                      offset: Offset(0, 10),
                      direction: PopoverDirection.bottomWithCenterAligned,
                    ),
                  ],
                ),
              ),
              const ExampleButton(
                label: "Bottom",
                offset: Offset(0, -10),
                direction: PopoverDirection.topWithCenterAligned,
              ),
            ],
          ),
        ),
        Column(
          children: [
            const ExampleButton(
              label: "Right top",
              offset: Offset(0, 10),
              direction: PopoverDirection.bottomWithRightAligned,
            ),
            Expanded(child: Container()),
            const ExampleButton(
              label: "Right bottom",
              offset: Offset(0, -10),
              direction: PopoverDirection.topWithRightAligned,
            ),
          ],
        )
      ]),
    );
  }
}