[Flutter] Calling a method with Provider.of(context) inside of dispose() method cause "Looking...

When I tried to call a method inside of State dispose method like below.

@override
void dispose() {
Provider.of<AppProvider>(context, listen: false).close();
super.dispose();
}


I got this.

The following assertion was thrown while finalizing the widget tree:
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.

When the exception was thrown, this was the stack
#0 Element._debugCheckStateIsActiveForAncestorLookup.<anonymous closure>
package:flutter/…/widgets/framework.dart:3508
#1 Element._debugCheckStateIsActiveForAncestorLookup
package:flutter/…/widgets/framework.dart:3522
#2 Element.getElementForInheritedWidgetOfExactType
package:flutter/…/widgets/framework.dart:3588
#3 Provider.of
packagerovider/src/provider.dart:219
#4 _MySecondPageState.dispose
package:test_space/main.dart:138
...


This is my example AppProvider

class AppProvider {
close() {}
}



and I wrapped MaterialApp with AppProvider

return Provider<AppProvider>(
create: (_) => AppProvider(),
child: MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: HomeScreen(),
},
),
);


I'm not sure how to do this 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. I'm currently using provider: ^4.0.2.

I used to do it the same, using Provider.of(context) inside of dispose(), without this exception before. Is this because new flutter version? Also, I realized there is the deactivate() method, should I use deactivate() method instead of dispose() method?

[UPDATED]

AppProvider _appProvider;
@override
void didChangeDependencies() {
_appProvider = Provider.of<AppProvider>(context, listen: false);
super.didChangeDependencies();
}

@override
void dispose() {
_appProvider.close();
super.dispose();
}


I could also use deactivate in a certain case

@override
void deactivate() {
Provider.of<AppProvider>(context, listen: false)
.close();
super.deactivate();
}

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