# 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.
```XML
...
```
### Entry point
Inside `main.dart` create an entry point for your Overlay widget;
NOTE: `MaterialApp` is required
```dart
// 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
```dart
FlutterOverlayApps.showOverlay(height: 300, width: 400, alignment: OverlayAlignment.center);
```
To close the overlay widget call
```dart
FlutterOverlayApps.closeOverlay();
```
To send data to and from Overlay widget, call
```dart
FlutterOverlayApps.sendDataToAndFromOverlay();
```
For listening to broadcasted data, stream the messages by calling
```dart
FlutterOverlayApps.overlayListener().listen((data) {
print(data);
});
```
### Code Example
```dart
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 createState() => _MyOverlaContentState();
}
class _MyOverlaContentState extends State {
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;
```dart
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;
```dart
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 