Flutter Error "elided 8 frames from package dart:async and package dart:async-patch"

flutter dart vscode-settings

10,403

you will get given error log when you forget to define both home in MaterialApp and root route "/" in the routes.

(Also You can only define either home in MaterialApp or / in routes)

import "package:flutter/material.dart";

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  Widget build(BuildContext context) {
    return MaterialApp(
      routes: {
        "/": (context) => InitialPage(),  //This is what you are missing i guess
        "/home": (context) => HomePage(),
        "/page1": (context) => Page1(),
      },
    );
  }
}

class InitialPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("Initial Page")),
      body: Center(
        child: RaisedButton(
          child: Text("Goto HomePage"),
          onPressed: () {
            Navigator.pushNamed(
                context,
                "/home"
            );
          },
        ),
      ),
    );
  }
}

class HomePage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("Home Page")),
      body: Center(
        child: RaisedButton(
          child: Text("Goto Page1"),
          onPressed: () {
            Navigator.pushNamed(
                context,
                "/page1"
            );
          },
        ),
      ),
    );
  }
}

class Page1 extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text("Page1")),
      body: Center(
        child: RaisedButton(
          child: Text("Button"),
          onPressed: () {},
        ),
      ),
    );
  }
}

10,403

Author by

C.Calzana

Updated on December 17, 2022

Comments

C.Calzana over 1 year

I keep getting this error when I try and run flutter application in Vscode. I have tried starting a default application and will get same error. I am unsure what is causing it, as I have used other projects and they worked fine, but it seems to be random.

It seemed to be ok, then when I started a new project that error started to appear. I have tried running old projects and the same error happens.

Full console output:

Launching lib\main.dart on SM J200Y in debug mode...
I/flutter (29160): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter (29160): The following assertion was thrown building IconTheme(color: Color(0xdd000000)):
I/flutter (29160): Could not find a generator for route RouteSettings("/", null) in the _WidgetsAppState.
I/flutter (29160): Generators for routes are searched for in the following order:
I/flutter (29160):  1. For the "/" route, the "home" property, if non-null, is used.
I/flutter (29160):  2. Otherwise, the "routes" table is used, if it has an entry for the route.
I/flutter (29160):  3. Otherwise, onGenerateRoute is called. It should return a non-null value for any valid route not
I/flutter (29160): handled by "home" and "routes".
I/flutter (29160):  4. Finally if all else fails onUnknownRoute is called.
I/flutter (29160): Unfortunately, onUnknownRoute was not set.
I/flutter (29160): The relevant error-causing widget was:
I/flutter (29160):   MaterialApp
[38;5;248mI/flutter (29160):[39;49m
I/flutter (29160): When the exception was thrown, this was the stack:
[38;5;244mI/flutter (29160): #0      _WidgetsAppState._onUnknownRoute.<anonymous closure>[39;49m
[38;5;244mI/flutter (29160): #1      _WidgetsAppState._onUnknownRoute[39;49m
[38;5;244mI/flutter (29160): #2      NavigatorState._routeNamed[39;49m
[38;5;244mI/flutter (29160): #3      NavigatorState.initState[39;49m
[38;5;244mI/flutter (29160): #4      StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #5      ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #6      Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #7      Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #8      ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #9      Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #10     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #11     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #12     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #13     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #14     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #15     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #16     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #17     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #18     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #19     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #20     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #21     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #22     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #23     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #24     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #25     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #26     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #27     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #28     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #29     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #30     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #31     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #32     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #33     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #34     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #35     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #36     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #37     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #38     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #39     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #40     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #41     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #42     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #43     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #44     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #45     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #46     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #47     StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #48     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #49     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #50     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #51     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #52     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #53     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #54     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #55     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #56     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #57     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #58     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #59     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #60     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #61     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #62     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #63     SingleChildRenderObjectElement.mount[39;49m
[38;5;244mI/flutter (29160): #64     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #65     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #66     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #67     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #68     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #69     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #70     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #71     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #72     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #73     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #74     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #75     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #76     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #77     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #78     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #79     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #80     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #81     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #82     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #83     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #84     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #85     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #86     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #87     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #88     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #89     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #90     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #91     Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #92     ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #93     ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #94     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #95     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #96     SingleChildRenderObjectElement.mount[39;49m
[38;5;244mI/flutter (29160): #97     Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #98     Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #99     ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #100    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #101    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #102    StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #103    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #104    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #105    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #106    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #107    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #108    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #109    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #110    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #111    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #112    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #113    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #114    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #115    StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #116    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #117    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #118    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #119    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #120    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #121    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #122    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #123    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #124    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #125    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #126    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #127    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #128    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #129    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #130    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #131    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #132    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #133    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #134    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #135    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #136    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #137    SingleChildRenderObjectElement.mount[39;49m
[38;5;244mI/flutter (29160): #138    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #139    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #140    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #141    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #142    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #143    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #144    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #145    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #146    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #147    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #148    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #149    StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #150    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #151    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #152    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #153    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #154    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #155    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #156    StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #157    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #158    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #159    Element.updateChild[39;49m
'Padding\tetstst\android\' is not recognized as an internal or external command,
operable program or batch file.
[38;5;244mI/flutter (29160): #160    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #161    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #162    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #163    StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #164    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #165    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #166    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #167    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #168    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #169    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #170    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #171    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #172    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #173    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #174    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #175    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #176    StatefulElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #177    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #178    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #179    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #180    ComponentElement.performRebuild[39;49m
[38;5;244mI/flutter (29160): #181    Element.rebuild[39;49m
[38;5;244mI/flutter (29160): #182    ComponentElement._firstBuild[39;49m
[38;5;244mI/flutter (29160): #183    ComponentElement.mount[39;49m
[38;5;244mI/flutter (29160): #184    Element.inflateWidget[39;49m
[38;5;244mI/flutter (29160): #185    Element.updateChild[39;49m
[38;5;244mI/flutter (29160): #186    RenderObjectToWidgetElement._rebuild[39;49m
[38;5;244mI/flutter (29160): #187    RenderObjectToWidgetElement.mount[39;49m
[38;5;244mI/flutter (29160): #188    RenderObjectToWidgetAdapter.attachToRenderTree.<anonymous closure>[39;49m
[38;5;244mI/flutter (29160): #189    BuildOwner.buildScope[39;49m
[38;5;244mI/flutter (29160): #190    RenderObjectToWidgetAdapter.attachToRenderTree[39;49m
[38;5;244mI/flutter (29160): #191    WidgetsBinding.attachRootWidget[39;49m
[38;5;244mI/flutter (29160): #192    WidgetsBinding.scheduleAttachRootWidget.<anonymous closure>[39;49m
[38;5;244mI/flutter (29160): #201    _Timer._runTimers  (dart:isolate-patch/timer_impl.dart:384:19)[39;49m
[38;5;244mI/flutter (29160): #202    _Timer._handleMessage  (dart:isolate-patch/timer_impl.dart:418:5)[39;49m
[38;5;244mI/flutter (29160): #203    _RawReceivePortImpl._handleMessage  (dart:isolate-patch/isolate_patch.dart:174:12)[39;49m
I/flutter (29160): (elided 8 frames from package dart:async and package dart:async-patch)
I/flutter (29160): ════════════════════════════════════════════════════════════════════════════════════════════════════
Error: Could not find or load main class org.gradle.wrapper.GradleWrapperMain
Gradle task assembleDebug failed with exit code 1
Exited (sigterm)

Project code:

import 'package:flutter/material.dart';

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home:Test(),
    );
  }
}

class Test extends StatelessWidget { // Hot restart will just retstart the widget, inside the stateless widget
  @override
  Widget build(BuildContext context) {
    return  Scaffold(
          // Proptery with a vaule
          appBar: AppBar(
            backgroundColor: Colors.amber[600],
            title: Text('My first app'),
            centerTitle: true, // Centers app bar title
          ),
          body: Center(// Everything below app bar, but centered in middle of screen
           /* child: Icon( // adds icon
              Icons.bluetooth,
              color: Colors.blue,
              size: 50.0,
            ), */
            child: RaisedButton.icon( // adds button and icon together
              onPressed: (){
                print ("You pressed me");
              },
              icon: Icon(
                Icons.mail
              ),
              label:  Text('Mail me'),
              color: Colors.amber,
            ),

              ),

            // outside of body
          floatingActionButton: FloatingActionButton( // Defines button
            onPressed: (){ // defines on pressed action
              print('You clicked me');
            },
            child: Text('click'),

            backgroundColor: Colors.blueAccent,

          ),
          ); 

  }
}```

Crazy Lazy Cat over 4 years

This is an issue from latest Flutter SDK which will shows last error log even from different project. you can just ignore this. See the flutter issue
C.Calzana over 4 years

@Crazy Lazy Cat but it still wont run my application.
Crazy Lazy Cat over 4 years

It seems an error from your route settings, can you you add your MaterialApp widget code.
C.Calzana over 4 years

@Crazy Lazy Cat updated post with project code
Crazy Lazy Cat over 4 years

this code runs without any error and installs the app successfully
C.Calzana over 4 years

@Crazy Lazy Cat I just created a new project and tried and now it works for me as well. I didn't change a thing, just copy and pasted code.

C.Calzana over 4 years

thanks that seemed to fix it. Can you explain what that route line does?
Crazy Lazy Cat over 4 years

The MaterialApp widget requires initial page. it can be done by simply defining home and it will be considered as / root route by default. You can also ignore home to manually define / in routes