<p dir="auto"><strong>Flutter environment:</strong></p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="[✓] Flutter (Channel beta, v0.7.3, on Linux, locale en_US.UTF-8)
[!] Android toolchain - develop for Android devices (Android SDK 28.0.1)
    ✗ Android license status unknown.
[✓] Android Studio (version 3.1)
[✓] IntelliJ IDEA Community Edition (version 2018.2)
[✓] VS Code (version 1.27.1)
[✓] Connected devices (1 available)"><pre class="notranslate"><code class="notranslate">[✓] Flutter (Channel beta, v0.7.3, on Linux, locale en_US.UTF-8)
[!] Android toolchain - develop for Android devices (Android SDK 28.0.1)
    ✗ Android license status unknown.
[✓] Android Studio (version 3.1)
[✓] IntelliJ IDEA Community Edition (version 2018.2)
[✓] VS Code (version 1.27.1)
[✓] Connected devices (1 available)
</code></pre></div>
<p dir="auto"><strong>Coding context:</strong><br>
calling steps: home widget -&gt; drawer item (routing) -&gt; ONE Widget : successful for the first time.<br>
then back to home widget-&gt; repeat above steps -&gt; bug as follow</p>
<p dir="auto"><strong>Bug information:</strong></p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="I/flutter ( 5796): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter ( 5796): The following assertion was thrown building Builder:
I/flutter ( 5796): 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3736 pos 12: '_state._widget ==
I/flutter ( 5796): null': is not true.
I/flutter ( 5796):
I/flutter ( 5796): Either the assertion indicates an error in the framework itself, or we should provide substantially
I/flutter ( 5796): more information in this error message to help you determine and fix the underlying cause.
I/flutter ( 5796): In either case, please report this assertion by filing a bug on GitHub:
I/flutter ( 5796):   https://github.com/flutter/flutter/issues/new
I/flutter ( 5796):
I/flutter ( 5796): When the exception was thrown, this was the stack:
I/flutter ( 5796): #2      new StatefulElement (package:flutter/src/widgets/framework.dart:3736:12)
I/flutter ( 5796): #3      StatefulWidget.createElement (package:flutter/src/widgets/framework.dart:789:42)
I/flutter ( 5796): #4      Element.inflateWidget (package:flutter/src/widgets/framework.dart:2917:40)
I/flutter ( 5796): #5      Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #6      SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #7      Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #8      Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #9      ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #10     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #11     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #12     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #13     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #14     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #15     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #16     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #17     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #18     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #19     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #20     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #21     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #22     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #23     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #24     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #25     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #26     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #27     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #28     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #29     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #30     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #31     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #32     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #33     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #34     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #35     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #36     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #37     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #38     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #39     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #40     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #41     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #42     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #43     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #44     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #45     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #46     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #47     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #48     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #49     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #50     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #51     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #52     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #53     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #54     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #55     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #56     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #57     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #58     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #59     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #60     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #61     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #62     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #63     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #64     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #65     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #66     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #67     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #68     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #69     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #70     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #71     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #72     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #73     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #74     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #75     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #76     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #77     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #78     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #79     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #80     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #81     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #82     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #83     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #84     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #85     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #86     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #87     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #88     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #89     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #90     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #91     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #92     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #93     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #94     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #95     RenderObjectElement.updateChildren (package:flutter/src/widgets/framework.dart:4449:32)
I/flutter ( 5796): #96     MultiChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4781:17)
I/flutter ( 5796): #97     Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #98     _TheatreElement.update (package:flutter/src/widgets/overlay.dart:507:16)
I/flutter ( 5796): #99     Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #100    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #101    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #102    StatefulElement.update (package:flutter/src/widgets/framework.dart:3811:5)
I/flutter ( 5796): #103    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #104    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #105    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #106    ProxyElement.update (package:flutter/src/widgets/framework.dart:3921:5)
I/flutter ( 5796): #107    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #108    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4673:14)
I/flutter ( 5796): #109    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #110    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #111    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #112    StatefulElement.update (package:flutter/src/widgets/framework.dart:3811:5)
I/flutter ( 5796): #113    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #114    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4673:14)
I/flutter ( 5796): #115    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #116    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4673:14)
I/flutter ( 5796): #117    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #118    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #119    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #120    BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2255:33)
I/flutter ( 5796): #121    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding&amp;PaintingBinding&amp;SemanticsBinding&amp;RendererBinding&amp;WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:653:20)
I/flutter ( 5796): #122    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding&amp;PaintingBinding&amp;SemanticsBinding&amp;RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:208:5)
I/flutter ( 5796): #123    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15)
I/flutter ( 5796): #124    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9)
I/flutter ( 5796): #125    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:842:5)
I/flutter ( 5796): #126    _invoke (dart:ui/hooks.dart:128:13)
I/flutter ( 5796): #127    _drawFrame (dart:ui/hooks.dart:117:3)
I/flutter ( 5796): (elided 2 frames from class _AssertionError)
I/flutter ( 5796): ═════════════════════════════════════════════════════════════════"><pre class="notranslate"><code class="notranslate">I/flutter ( 5796): ══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter ( 5796): The following assertion was thrown building Builder:
I/flutter ( 5796): 'package:flutter/src/widgets/framework.dart': Failed assertion: line 3736 pos 12: '_state._widget ==
I/flutter ( 5796): null': is not true.
I/flutter ( 5796):
I/flutter ( 5796): Either the assertion indicates an error in the framework itself, or we should provide substantially
I/flutter ( 5796): more information in this error message to help you determine and fix the underlying cause.
I/flutter ( 5796): In either case, please report this assertion by filing a bug on GitHub:
I/flutter ( 5796):   https://github.com/flutter/flutter/issues/new
I/flutter ( 5796):
I/flutter ( 5796): When the exception was thrown, this was the stack:
I/flutter ( 5796): #2      new StatefulElement (package:flutter/src/widgets/framework.dart:3736:12)
I/flutter ( 5796): #3      StatefulWidget.createElement (package:flutter/src/widgets/framework.dart:789:42)
I/flutter ( 5796): #4      Element.inflateWidget (package:flutter/src/widgets/framework.dart:2917:40)
I/flutter ( 5796): #5      Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #6      SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #7      Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #8      Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #9      ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #10     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #11     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #12     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #13     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #14     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #15     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #16     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #17     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #18     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #19     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #20     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #21     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #22     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #23     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #24     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #25     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #26     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #27     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #28     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #29     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #30     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #31     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #32     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #33     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #34     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #35     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #36     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #37     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #38     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #39     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #40     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #41     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #42     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #43     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #44     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #45     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #46     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #47     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #48     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #49     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #50     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #51     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #52     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #53     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #54     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #55     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #56     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #57     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #58     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #59     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #60     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #61     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #62     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #63     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #64     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #65     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #66     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #67     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #68     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #69     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #70     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #71     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #72     SingleChildRenderObjectElement.mount (package:flutter/src/widgets/framework.dart:4666:14)
I/flutter ( 5796): #73     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #74     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #75     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #76     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #77     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #78     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #79     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #80     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #81     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #82     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #83     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #84     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #85     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #86     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #87     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #88     ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #89     Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #90     ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3634:5)
I/flutter ( 5796): #91     StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3781:11)
I/flutter ( 5796): #92     ComponentElement.mount (package:flutter/src/widgets/framework.dart:3629:5)
I/flutter ( 5796): #93     Element.inflateWidget (package:flutter/src/widgets/framework.dart:2919:14)
I/flutter ( 5796): #94     Element.updateChild (package:flutter/src/widgets/framework.dart:2722:12)
I/flutter ( 5796): #95     RenderObjectElement.updateChildren (package:flutter/src/widgets/framework.dart:4449:32)
I/flutter ( 5796): #96     MultiChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4781:17)
I/flutter ( 5796): #97     Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #98     _TheatreElement.update (package:flutter/src/widgets/overlay.dart:507:16)
I/flutter ( 5796): #99     Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #100    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #101    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #102    StatefulElement.update (package:flutter/src/widgets/framework.dart:3811:5)
I/flutter ( 5796): #103    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #104    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #105    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #106    ProxyElement.update (package:flutter/src/widgets/framework.dart:3921:5)
I/flutter ( 5796): #107    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #108    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4673:14)
I/flutter ( 5796): #109    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #110    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #111    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #112    StatefulElement.update (package:flutter/src/widgets/framework.dart:3811:5)
I/flutter ( 5796): #113    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #114    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4673:14)
I/flutter ( 5796): #115    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #116    SingleChildRenderObjectElement.update (package:flutter/src/widgets/framework.dart:4673:14)
I/flutter ( 5796): #117    Element.updateChild (package:flutter/src/widgets/framework.dart:2711:15)
I/flutter ( 5796): #118    ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3665:16)
I/flutter ( 5796): #119    Element.rebuild (package:flutter/src/widgets/framework.dart:3507:5)
I/flutter ( 5796): #120    BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2255:33)
I/flutter ( 5796): #121    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding&amp;PaintingBinding&amp;SemanticsBinding&amp;RendererBinding&amp;WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:653:20)
I/flutter ( 5796): #122    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding&amp;PaintingBinding&amp;SemanticsBinding&amp;RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:208:5)
I/flutter ( 5796): #123    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:990:15)
I/flutter ( 5796): #124    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:930:9)
I/flutter ( 5796): #125    _WidgetsFlutterBinding&amp;BindingBase&amp;GestureBinding&amp;ServicesBinding&amp;SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:842:5)
I/flutter ( 5796): #126    _invoke (dart:ui/hooks.dart:128:13)
I/flutter ( 5796): #127    _drawFrame (dart:ui/hooks.dart:117:3)
I/flutter ( 5796): (elided 2 frames from class _AssertionError)
I/flutter ( 5796): ═════════════════════════════════════════════════════════════════
</code></pre></div>
<p dir="auto">For example, I'm trying to find documentation on NetworkImage, to load images from my server.<br>
Google (and search on the flutter.io) both point me to <a href="https://docs.flutter.io/flutter/material/Image/Image.network.html" rel="nofollow">https://docs.flutter.io/flutter/material/Image/Image.network.html</a> which returns 404.</p>