How to call child method from parent for another widget - flutter

Question

main.dart
import 'dart:io';
import 'package:audioplayer/audioplayer.dart';
import 'package:flutter/material.dart';
import 'dart:async';
import 'package:path_provider/path_provider.dart';
import 'package:record_mp3/record_mp3.dart';
import 'package:permission_handler/permission_handler.dart';
import 'regitration.dart';
//import 'voiceCreate.dart';
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
#override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
String statusText = "";
bool isComplete = false;
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Builder(
builder: (context) => Scaffold(
drawer: Drawer(
elevation: 2.0,
child: ListView(
children: <Widget>[
ListTile(
title: Text('Home'),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) {
return MyApp();
},
),
);
},
),
ListTile(
title: Text('Sign up'),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) {
return LoginScreen();
},
),
);
},
),
ListTile(
title: Text('Sign in'),
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) {
return LoginScreen();
},
),
);
// add sign in page
},
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: () {
// Add your onPressed code here!
},
child: Icon(Icons.add),
backgroundColor: Colors.tealAccent.shade700,
),
backgroundColor: Colors.grey.shade900,
appBar: AppBar(
title: Text('Myvo'),
centerTitle: true,
backgroundColor: Colors.tealAccent.shade700,
),
body: Column(children: [
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
Expanded(
child: GestureDetector(
child: IconButton(
icon: Icon(Icons.mic),
color: Colors.white,
iconSize: 40,
onPressed: () async {
startRecord();
}),
),
),
Expanded(
child: GestureDetector(
child: IconButton(
icon: Icon(Icons.pause),
color: Colors.white,
iconSize: 40,
onPressed: () async {
pauseRecord();
}),
),
),
Expanded(
child: GestureDetector(
child: IconButton(
icon: Icon(Icons.stop),
color: Colors.white,
iconSize: 40,
onPressed: () async {
stopRecord();
}),
),
),
],
),
Padding(
padding: const EdgeInsets.only(top: 20.0),
child: Text(
statusText,
style: TextStyle(color: Colors.red, fontSize: 20),
),
),
GestureDetector(
behavior: HitTestBehavior.opaque,
onTap: () {
play();
},
child: Container(
margin: EdgeInsets.only(top: 30),
alignment: AlignmentDirectional.center,
width: 100,
height: 50,
child: isComplete && recordFilePath != null
? Text(
"play",
style: TextStyle(color: Colors.red, fontSize: 20),
)
: Container(),
),
),
]),
),
),
);
}
Future<bool> checkPermission() async {
if (!await Permission.microphone.isGranted) {
PermissionStatus status = await Permission.microphone.request();
if (status != PermissionStatus.granted) {
return false;
}
}
return true;
}
void startRecord() async {
bool hasPermission = await checkPermission();
if (hasPermission) {
statusText = "Recording...";
recordFilePath = await getFilePath();
isComplete = false;
RecordMp3.instance.start(recordFilePath, (type) {
statusText = "Record error--->$type";
setState(() {});
});
} else {
statusText = "No microphone permission";
}
setState(() {});
}
void pauseRecord() {
if (RecordMp3.instance.status == RecordStatus.PAUSE) {
bool s = RecordMp3.instance.resume();
if (s) {
statusText = "Recording...";
setState(() {});
}
} else {
bool s = RecordMp3.instance.pause();
if (s) {
statusText = "Recording pause...";
setState(() {});
}
}
}
void stopRecord() {
bool s = RecordMp3.instance.stop();
if (s) {
statusText = "Record complete";
isComplete = true;
setState(() {});
}
}
void resumeRecord() {
bool s = RecordMp3.instance.resume();
if (s) {
statusText = "Recording...";
setState(() {});
}
}
String recordFilePath;
void play() {
if (recordFilePath != null && File(recordFilePath).existsSync()) {
AudioPlayer audioPlayer = AudioPlayer();
audioPlayer.play(recordFilePath, isLocal: true);
}
}
int i = 0;
Future<String> getFilePath() async {
Directory storageDirectory = await getApplicationDocumentsDirectory();
String sdPath = storageDirectory.path + "/record";
var d = Directory(sdPath);
if (!d.existsSync()) {
d.createSync(recursive: true);
}
return sdPath + "/test_${i++}.mp3";
}
}
I want to call the VoiceCreate function when clicking on onPressed
voiceCreate.dart
import 'package:flutter/material.dart';
import 'main.dart';
class VoiceCreate extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
backgroundColor: Colors.blueGrey,
body: Center(
child: IconButton(
icon: Icon(Icons.mic),
color: Colors.white,
iconSize: 70,
onPressed: () {}),
),
),
);
}
}
I want to call startRecord method from main.dart when clicking on onPressed

Answer 1

If you check the code of IconButton you'll see that onPressed is a VoidCallback, you can try to imitate the logic to do the same
class VoiceCreate extends StatelessWidget {
final VoidCallback onPressed;
VoiceCreate({this.onPressed});
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
backgroundColor: Colors.blueGrey,
body: Center(
child: IconButton(
icon: Icon(Icons.mic),
color: Colors.white,
iconSize: 70,
onPressed: onPressed),
),
),
);
}
}
And in main just call your widget VoiceCreate with an onPressed parameter
VoiceCreate(
onPressed: () => startRecord
)
edited code here. Still the startRecord() is not working. VoiceCreate() is working
floatingActionButton: FloatingActionButton(
onPressed: () {
Navigator.push(
context,
MaterialPageRoute(builder: (context) {
return VoiceCreate(onPressed: startRecord);
}),
);
},
// Add your onPressed code here!
child: Icon(Icons.add),
backgroundColor: Colors.tealAccent.shade700,
),
class VoiceCreate extends StatelessWidget {
final VoidCallback onPressed;
VoiceCreate({this.onPressed});
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
backgroundColor: Colors.blueGrey,
body: Center(
child: IconButton(
icon: Icon(Icons.mic),
color: Colors.white,
iconSize: 70,
onPressed: onPressed),
),
),
);
}
}

Answer 2

You could do this by using shared view model across need widgets, like so:
I'd recommend to use this approach instead of callbacks and Stateful widgets
import 'package:flutter/material.dart';
import 'package:get/get.dart';
class Parent extends StatelessWidget {
#override
Widget build(BuildContext context) {
return GetBuilder<CommonViewModel>(
init: CommonViewModel(),
builder: (model) {
return Scaffold(
body: Column(
children: [
RaisedButton(onPressed: () => model.parentMethod(0)),
RaisedButton(onPressed: () => model.childMethod('call from parent')),
],
),
);
},
);
}
}
class Child extends StatelessWidget {
#override
Widget build(BuildContext context) {
return GetBuilder<CommonViewModel>(
builder: (model) {
return Scaffold(
body: Column(
children: [
RaisedButton(onPressed: () => model.childMethod('call from child')),
RaisedButton(onPressed: () => model.parentMethod(100)),
],
),
);
},
);
}
}
class CommonViewModel extends GetxController {
void parentMethod(int argument) {
print('Parent method $argument');
}
void childMethod(String argument) {
print('Child method $argument');
}
}