Show Dialog In InitState Unhandled Exception: Looking up a deactivated widget's ancestor is unsafe - flutter

Question

At first time screen appears, i want check if user GPS is enable and Location Permission is granted. Then if one of them is not fulfilled , i show dialog to open app setting.
Source Code
_initPermission(BuildContext context) async {
final geolocationStatus = await commonF.getGeolocationPermission();
final gpsStatus = await commonF.getGPSService();
if (geolocationStatus != GeolocationStatus.granted) {
showDialog(
context: context,
builder: (ctx) {
return commonF.showPermissionLocation(ctx);
},
);
} else if (!gpsStatus) {
showDialog(
context: context,
builder: (ctx) {
return commonF.showPermissionGPS(ctx);
},
);
}
}
Then i called this function in initState like this :
InitState
void initState() {
super.initState();
Future.delayed(Duration(milliseconds: 50)).then((_) => _initPermission(context));
}
The problem is , every first time the screen appears it will give me error like this :
Error
[ERROR:flutter/lib/ui/ui_dart_state.cc(166)] Unhandled Exception: Looking up a deactivated widget's ancestor is unsafe.
At this point the state of the widget's element tree is no longer stable.
To safely refer to a widget's ancestor in its dispose() method, save a reference to the ancestor by calling dependOnInheritedWidgetOfExactType() in the widget's didChangeDependencies() method.
What i have done :
Change InitState like this
//1
WidgetsBinding.instance.addPostFrameCallback((_) {
_initPermission(context);
});
//2
SchedulerBinding.instance.addPostFrameCallback((_) => _initPermission(context));
//3
Timer.run(() {
_initPermission(context);
})
Adding Global Key For Scaffold
final GlobalKey<ScaffoldState> _scaffoldKey = GlobalKey<ScaffoldState>();
Scaffold(
key: _scaffoldKey,
Searching similiar problem with me
Show Dialog In Initstate
Looking up a deactivated widget's ancestor is unsafe
Load Data In Initstate
The results that I have done is nothing , the error still appear in first time screen appear.
But strangely, this only happens when first time screen appear . When i do Hot Restart the error message is gone.
[Failed if screen first time appear]
[Hot restart , error gone]

Answer 1

I have no way to test it (I dont have the GPS package) but try changing
Future.delayed(Duration(milliseconds: 50)).then((_) => _initPermission(context));
to
Future.delayed(Duration(milliseconds: 50)).then((_) => _initPermission()); //this inside the initstate
_initPermission() async{
final geolocationStatus = await commonF.getGeolocationPermission();
final gpsStatus = await commonF.getGPSService();
if (geolocationStatus != GeolocationStatus.granted) {
await showDialog(
context: context,
builder: (ctx) => commonF.showPermissionLocation
},
);
} else if (!gpsStatus) {
await showDialog(
context: context,
builder: (ctx) => commonF.showPermissionGPS
},
);
}
} // the stateful widget can use the context in all its methods without passing it as a parameter
The error dissapears in hot restart because it just refresh the state of the widget, but it's already created (If you do hot restart and print something inside the initState, for example print('This is init');, you wont see it either because the refresh doesn't dispose and init the widget, so it won't run that piece of code again)
EDIT
Based on your gist I just made a minimal reproducible example and run with no problem in DartPad, later I will try it on VS but for now can you check if there is anything different
enum GeolocationStatus{granted, denied} //this is just for example
class MyWidget extends StatefulWidget {
#override
_MyWidgetState createState() => _MyWidgetState();
}
class _MyWidgetState extends State<MyWidget> {
showPermissionGPS() {
return AlertDialog(
title: Text('GPSStatus'),
);
}
_showPermissionLocation() {
return AlertDialog(
title: Text('Permission Localization'),
);
}
#override
initState(){
super.initState();
Future.delayed(Duration(milliseconds: 50)).then((_) => _initPermission());
}
_initPermission() async{
final geolocationStatus = await Future<GeolocationStatus>.value(GeolocationStatus.granted); //mocked future with a response to test
final gpsStatus = await Future<bool>.value(false); //mocked future with a response to test
if (geolocationStatus != GeolocationStatus.granted) {
await showDialog(
context: context,
builder: (ctx) => _showPermissionLocation() //this mock commonF.showPermissionLocation and returns an AlertDialog
);
} else if (!gpsStatus) {
await showDialog(
context: context,
builder: (ctx) => _showPermissionGPS() //this mock commonF.showPermissionGPS and returns an AlertDialog
);
}
}
#override
Widget build(BuildContext context) {
return Text('My text');
}
}