PageView homepage sometimes does not load on startup in release mode

flutter dart flutter-dependencies flutter-state

270

Solution 1

I was getting the same Issue and i found that is a flutter bug :)

In the meanwhile, there is a small hack to avoid this issue : add a small delay before calling runApp

void main() async {
  await Future.delayed(const Duration(milliseconds: 200));
  runApp(const MyApp());
}

Solution 2

I was getting the same message while using PageView and launching the app in release mode. My suggestion would be to use ListView instead of PageView. It's just a workaround since I don't know what is causing the issue either. You should also use a ScrollController instead of a PageController because using a PageController is causing the same issue. Hope this helps!

270

Author by

iamhx

Updated on January 05, 2023

Comments

iamhx over 1 year

I encountered a rather strange bug when my app is launching in release mode:

I had followed this answer to preserve my pages for my BottomNavigationBar using PageView and AutomaticKeepAliveClientMixin. In debug mode, this bug does not happen.

home.dart

import 'package:flutter/material.dart';
import 'package:lottery_rewards/controller.dart';

class HomeView extends StatefulWidget {
  const HomeView({Key? key}) : super(key: key);

  @override
  State<StatefulWidget> createState() => _HomeView();
}

class _HomeView extends State<HomeView>
    with AutomaticKeepAliveClientMixin<HomeView> {
  @override
  Widget build(BuildContext context) {
    super.build(context);
    return Column(
      children: [
        const MainAppBar(),
        Expanded(
          child: Center(
            child: TextButton(
              child: const Text('Home'),
              onPressed: () {
              },
            ),
          ),
        )
      ],
    );
  }

  @override
  bool get wantKeepAlive => true;
}

Also in the terminal, it says that "Null check operator used on a null value", however I do not know where I used this code.

I/flutter (29449): Null check operator used on a null value
I/flutter (29449): #0      _PagePosition.applyViewportDimension (package:flutter/src/widgets/page_view.dart:455)
I/flutter (29449): #1      RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:1456)
I/flutter (29449): #2      RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #3      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #4      RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #5      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #6      RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #7      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #8      RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #9      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #10     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #11     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #12     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #13     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #14     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #15     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #16     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #17     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #18     RenderCustomPaint.performLayout (package:flutter/src/rendering/custom_paint.dart:545)
I/flutter (29449): #19     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #20     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #21     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #22     _RenderLayoutBuilder.performLayout (package:flutter/src/widgets/layout_builder.dart:318)
I/flutter (29449): #23     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #24     MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:171)
I/flutter (29449): #25     _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:1003)
I/flutter (29449): #26     MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:240)
I/flutter (29449): #27     RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:403)
I/flutter (29449): #28     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #29     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #30     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #31     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #32     _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1376)
I/flutter (29449): #33     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #34     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #35     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #36     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #37     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #38     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #39     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #40     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #41     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #42     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #43     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #44     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #45     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #46     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #47     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #48     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #49     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #50     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #51     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #52     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #53     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #54     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #55     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #56     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #57     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #58     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #59     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #60     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #61     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #62     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #63     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #64     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #65     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #66     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #67     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #68     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #69     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #70     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #71     RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:3462)
I/flutter (29449): #72     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #73     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #74     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #75     _RenderTheatre.performLayout (package:flutter/src/widgets/overlay.dart:749)
I/flutter (29449): #76     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #77     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #78     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #79     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #80     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #81     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #82     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #83     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #84     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #85     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #86     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #87     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #88     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #89     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:116)
I/flutter (29449): #90     RenderObject.layout (package:flutter/src/rendering/object.dart:1915)
I/flutter (29449): #91     RenderView.performLayout (package:flutter/src/rendering/view.dart:165)
I/flutter (29449): #92     RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1757)
I/flutter (29449): #93     PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:887)
I/flutter (29449): #94     RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:504)
I/flutter (29449): #95     WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:892)
I/flutter (29449): #96     RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:370)
I/flutter (29449): #97     SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1146)
I/flutter (29449): #98     SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1083)
I/flutter (29449): #99     SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:997)

Please help! What is causing this issue?

iamhx over 1 year

Nice and simple hack until they push the fix to the stable branch!
Luca Guarro over 1 year

How did you discover that it is a flutter bug? Is it documented by the flutter team somewhere?