flutter_overlay_apps

Android plugin for displaying flutter app over other apps

Usage

Add dependency to pubspec.yaml file

Android

You'll need to add the SYSTEM_ALERT_WINDOW permission and OverlayService to your Android Manifest.

    <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
    <application>
        ...
        <service
           android:name="com.phan_tech.flutter_overlay_apps.OverlayService"
           android:exported="false" />
    </application>

Entry point

Inside main.dart create an entry point for your Overlay widget; NOTE: MaterialApp is required

// overlay entry point
@pragma("vm:entry-point")
void showOverlay() {
  runApp(const MaterialApp(
    debugShowCheckedModeBanner: false,
    home: Material(child: Text("My overlay"))
  ));
}

Methods

To open an overlay, call FlutterOverlayApps.showOverlay(). Default height & width is fill screen

FlutterOverlayApps.showOverlay(height: 300, width: 400, alignment: OverlayAlignment.center);

To close the overlay widget call

FlutterOverlayApps.closeOverlay();

To send data to and from Overlay widget, call

FlutterOverlayApps.sendDataToAndFromOverlay(<data>);

For listening to broadcasted data, stream the messages by calling

FlutterOverlayApps.overlayListener().listen((data) {
    print(data);
});

Code Example

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

import 'package:flutter_overlay_apps/flutter_overlay_apps.dart';

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

// overlay entry point
@pragma("vm:entry-point")
void showOverlay() {
  runApp(const MaterialApp(
    debugShowCheckedModeBanner: false,
    home: MyOverlaContent()
  ));
}


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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Plugin example app'),
        ),
        body: Center(
          child: ElevatedButton(
            onPressed: () async {

              // Open overlay
              await FlutterOverlayApps.showOverlay(height: 300, width: 400, alignment: OverlayAlignment.center);

              // send data to ovelay
              await Future.delayed(const Duration(seconds: 2));
              FlutterOverlayApps.sendDataToAndFromOverlay("Hello from main app");
            }, 
            child: const Text("showOverlay")
          ),
        ),
      ),
    );
  }
}



class MyOverlaContent extends StatefulWidget {
  const MyOverlaContent({ Key? key }) : super(key: key);

  @override
  State<MyOverlaContent> createState() => _MyOverlaContentState();
}

class _MyOverlaContentState extends State<MyOverlaContent> {
  String _dataFromApp = "Hey send data";

  @override
  void initState() {
    super.initState();

    // lisent for any data from the main app
    FlutterOverlayApps.overlayListener().listen((event) {
      setState(() {
        _dataFromApp = event.toString();
      });
    });
  }

  @override
  Widget build(BuildContext context) {
    return Material(
      child: InkWell(
        onTap: (){
          // close overlay
          FlutterOverlayApps.closeOverlay();
        },
        child: Card(
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(16),
          ),
          child: Center(child: Text(_dataFromApp, style: const TextStyle(color: Colors.red),)),
        ),
      ),
    );
  }
}

Android back button

The back navigation button on android will close the overlay app. To prevent this, set closeOnBackButton to false. Example;

await FlutterOverlayApps.showOverlay(
  height: 300,
  closeOnBackButton: false,
  alignment: OverlayAlignment.center);

When closeOnBackButton is set to false, an action will be sent via the stream controller. You can get the action like the example below;

var overlayStreamController = FlutterOverlayApps.overlayListener();

overlayStreamController.stream.listen((event) {
  if(event['method'] == 'backButton'){
    // handle back button 
    if(mounted && Navigator.of(context).canPop()){
      Navigator.of(context).pop();
    }
  }
})

Support the plugin