Package:flutter/src/widgets/overlay.dart': Failed assertion: line 133 pos 12: '_overlay != null':

[ravipatel147]

to Reproduce

Create Singleton class. Class have a Two static method. method name is show and hide, show method
accept context as a parameter and add entry into Overlay and hide method remove that overlay. Class code is as below

import 'package:flutter/material.dart';
import 'package:harshal/utils/loger.dart';

class InternetError {
  static final _instance = new InternetError.internal();
  factory InternetError() => _instance;
  InternetError.internal();

  static OverlayEntry entry = null;

  static void show(context) => addOverlayEntry(context);
  static void hide() => removeOverlay();

  bool get isshow => entry != null;

  static addOverlayEntry(context) {
    if (entry != null) return;
    entry = new OverlayEntry(builder: (BuildContext context) {
      return LayoutBuilder(builder: (_, BoxConstraints constraints) {
        return new Material(
          color: Colors.transparent,
          child: new Center(
            child: new Container(
              width: 90.0,
              height: 80.0,
              child: Column(
                children: <Widget>[
                  new CircularProgressIndicator(
                      strokeWidth: 4.0,
                      valueColor:
                          new AlwaysStoppedAnimation<Color>(Colors.red.shade400)),
                          new Text("No internet")
                ],
              ),
            ),
          ),
        );
      });
    });

   addoverlay(entry, context);
  }

  static addoverlay(OverlayEntry entry, context) async {
    Overlay.of(context).insert(entry);
  }

  static removeOverlay() {
    logger(entry == null);
    entry?.remove();
    entry = null;
  }
}

1. First use show static method is show overlay successfully
2. When call hide method then below Exception was throw

Logs

: ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter (15138): The following assertion was thrown building MediaQuery(MediaQueryData(size: Size(411.4, 683.4),
I/flutter (15138): devicePixelRatio: 3.5, textScaleFactor: 1.0, padding: EdgeInsets(0.0, 24.0, 0.0, 0.0), viewInsets:
I/flutter (15138): EdgeInsets.zero, alwaysUse24HourFormat: false)):
I/flutter (15138): 'package:flutter/src/widgets/overlay.dart': Failed assertion: line 133 pos 12: '_overlay != null':
I/flutter (15138): is not true.
I/flutter (15138): Either the assertion indicates an error in the framework itself, or we should provide substantially
I/flutter (15138): more information in this error message to help you determine and fix the underlying cause.
I/flutter (15138): In either case, please report this assertion by filing a bug on GitHub:
I/flutter (15138):   https://github.com/flutter/flutter/issues/new
I/flutter (15138): When the exception was thrown, this was the stack:
I/flutter (15138): #2      OverlayEntry.remove (package:flutter/src/widgets/overlay.dart)
I/flutter (15138): #3      InternetError.removeOverlay (package:harshal/ui/sidebar/no_internet.dart:50:12)
I/flutter (15138): #4      InternetError.hide (package:harshal/ui/sidebar/no_internet.dart:12:25)
I/flutter (15138): #5      new SideBarState (package:harshal/ui/sidebar/sidebar.dart:34:20)
I/flutter (15138): #6      SideBar.createState (package:harshal/ui/sidebar/sidebar.dart:18:16)
I/flutter (15138): #7      new StatefulElement (package:flutter/src/widgets/framework.dart:3710:23)
I/flutter (15138): #8      StatefulWidget.createElement (package:flutter/src/widgets/framework.dart:789:42)
I/flutter (15138): #9      Element.inflateWidget (package:flutter/src/widgets/framework.dart:2905:40)
I/flutter (15138): #10     Element.updateChild (package:flutter/src/widgets/framework.dart:2710:12)
I/flutter (15138): #11     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4654:14)
I/flutter (15138): #12     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2907:14)
I/flutter (15138): #13     MultiChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4759:32)
I/flutter (15138): #14     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2907:14)
I/flutter (15138): #15     Element.updateChild (package:flutter/src/widgets/framework.dart:2710:12)
I/flutter (15138): #16     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3653:16)
I/flutter (15138): #17     Element.rebuild (package:flutter/src/widgets/framework.dart:3495:5)
I/flutter (15138): #18     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3622:5)
I/flutter (15138): #19     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3617:5)
I/flutter (15138): #20     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2907:14)
I/flutter (15138): #21     Element.updateChild (package:flutter/src/widgets/framework.dart:2710:12)

Doctor

Doctor summary (to see all details, run flutter doctor -v):
[√] Flutter (Channel beta, v0.5.1, on Microsoft Windows [Version 10.0.17134.165], locale en-IN)
[√] Android toolchain - develop for Android devices (Android SDK 28.0.1)
[√] Android Studio (version 3.1)
    X Flutter plugin not installed; this adds Flutter specific functionality.
    X Dart plugin not installed; this adds Dart specific functionality.
[!] VS Code, 64-bit edition (version 1.25.1)
[√] Connected devices (1 available)

! Doctor found issues in 1 category.

[johndavid92]

@ravipatel147 Did you find any solution for this issue?

[Qiang11]

Did you find any solution for this issue?

[github-actions]

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