Flutter list view - An unofficial list view for flutter

Last update: Dec 15, 2022

Related tags

Overview

Flutter List View

I don't like official list view. There are some features don't provide and jumpTo performance is not good. I rewrite the list supported these features in [Features] sections

Features

Support jump to index
Jump to index is not support in listview. But it is useful function
Support keep position
If some data insert before other items, It will scroll down. Some chat software may want to keep the position not scroll down when new message coming.
Support show top in reverse mode if the data can't fill full viewport.
Support header sticky
Support integrate pull_to_refresh
Support scroll to specify index when initialize data
Performance
When listview jump to somewhere, The items which layout before the position will always loaded. It is not realy lazy loading.

Screen

Example

FlutterListView(
      delegate: FlutterListViewDelegate(
    (BuildContext context, int index) =>
        ListTile(title: Text('List Item ${data[index]}')),
    childCount: data.length,
  ))

Jump to index

flutterListViewController.jumpToIndex(100);

/// Declare
FlutterListViewController controller = FlutterListViewController();
...
controller.sliverController
                      .jumpToIndex(100);
...
FlutterListView(
  controller: controller,
  delegate: FlutterListViewDelegate(
    (BuildContext context, int index) => Container(
      color: Colors.white,
      child: ListTile(title: Text('List Item ${data[index]}')),
    ),
    childCount: data.length,
  ))

If you want better user expierence, preferItemHeight or onItemHeight may set to.

preferItemHeight The package don't know the item's height, If you don't set, package alway think the item height is 50 util layout the item. If you know the height, you should set it.
onItemHeight like preferItemHeight, the function will used to get height of each item util the item layout.

Keep Position

_renderList() {
  return FlutterListView(
      reverse: true,
      delegate: FlutterListViewDelegate(
          (BuildContext context, int index) => Align(
                alignment: Alignment.centerRight,
                child: Padding(
                  padding: const EdgeInsets.all(10.0),
                  child: Container(
                    decoration: const BoxDecoration(
                        color: Colors.blue,
                        borderRadius: BorderRadius.only(
                            topLeft: Radius.circular(20),
                            bottomLeft: Radius.circular(20),
                            bottomRight: Radius.circular(20))),
                    child: Padding(
                      padding: const EdgeInsets.all(10.0),
                      child: Text(
                        chatListContents[index].msg,
                        style: const TextStyle(
                            fontSize: 14.0, color: Colors.white),
                      ),
                    ),
                  ),
                ),
              ),
          childCount: chatListContents.length,
          onItemKey: (index) => chatListContents[index].id.toString(),
          keepPosition: true,
          keepPositionOffset: 80,
          firstItemAlign: FirstItemAlign.end));
}

Notice: Keep positoin need implement onItemKey, the onItemKey used to identify the unique of item. The key should difference with other items' key. We use the key to know what position you insert to current list. if you insert a item before the rendered item, package should increase the scrollOffset.

Sticky header

Widget _renderHeader(String text) {
  return Container(
    color: const Color(0xFFF3F4F5),
    child: Padding(
      padding: const EdgeInsets.symmetric(horizontal: 16.0, vertical: 12.0),
      child: Text(
        text,
        style: const TextStyle(fontSize: 18, color: Color(0xFF767676)),
      ),
    ),
  );
}

Widget _renderItem(CountryModel itemData) {
  return Padding(
      padding: const EdgeInsets.only(right: 12.0),
      child: ListTile(
          title: Text(itemData.name), trailing: Text(itemData.phoneCode)));
}

@override
Widget build(BuildContext context) {
  return Scaffold(
    appBar: AppBar(title: const Text("Stick Header")),
    body: FlutterListView(
        delegate: FlutterListViewDelegate(
          (BuildContext context, int index) {
            var data = _countries[index];
            if (data is AlphabetHeader) {
              return _renderHeader(data.alphabet);
            } else {
              return _renderItem(data as CountryModel);
            }
          },
          childCount: _countries.length,
          onItemSticky: (index) => _countries[index] is AlphabetHeader,
        ),
        controller: controller),
  );
}

You can also check doc/stickyHeader.md

Integrate pull_to_refresh

@override
Widget build(BuildContext context) {
  return Scaffold(
    appBar: AppBar(
      title: const Text("Intergrate pull to refresh in list"),
    ),
    body: SmartRefresher(
      enablePullDown: true,
      enablePullUp: true,
      header: const WaterDropHeader(),
      footer: CustomFooter(
        builder: (context, mode) {
          Widget body;
          if (mode == LoadStatus.idle) {
            body = const Text("pull up load");
          } else if (mode == LoadStatus.loading) {
            body = const CupertinoActivityIndicator();
          } else if (mode == LoadStatus.failed) {
            body = const Text("Load Failed!Click retry!");
          } else if (mode == LoadStatus.canLoading) {
            body = const Text("release to load more");
          } else {
            body = const Text("No more Data");
          }
          return SizedBox(
            height: 55.0,
            child: Center(child: body),
          );
        },
      ),
      controller: _refreshController,
      onRefresh: _onRefresh,
      onLoading: _onLoading,
      child: FlutterListView(
          delegate: FlutterListViewDelegate(
        (BuildContext context, int index) =>
            ListTile(title: Text('List Item ${data[index]}')),
        childCount: data.length,
      )),
    ),
  );
}

Comments

Restoring scroll position not reliable
Hello all. Most of flutter_list_view works fine, but I have the following problem:

In my app, there is a list of chat messages that are rendered as HTML using flutter_html. Each message can have its own height, which I can't set myself.

When I try to initialize the list with initIndex and initOffset, sometimes the scroll position is just wrong. This depends on the preferItemHeight value. If I set a small value, the scroll position is fine when there are only single-line messages, but breaks for large messages. If a large value is set, the scroll position is fine when there are large values, but has problems when there are many one-line items.

It seems that the initial scroll position is restored with preferItemHeight or onItemHeight(...), just before the actual height of the item is known.

I tried to create a reproducible example, but was not able to create this behavior with test data.

Code I can currently share:

FlutterListView( key: ObjectKey(...), controller: viewController, delegate: FlutterListViewDelegate( (BuildContext context, int index) { ... return Container( // container is required, otherwise there will be layouting errors child: XXX(), ); }, onItemKey: (index) { ... }, onItemHeight: (index) { ... }, childCount: itemCount, initIndex: initialScrollIndex, initOffset: initialAlignment, firstItemAlign: FirstItemAlign.end, ), );

I hope you find an approach to find the problem
opened by anormal81 20

Got incorrect position using renderObject when list is reversed and firstItemAlign is end

Only occurs when items are not enough to fill the screen It's easy to reproduce

Scaffold(
      body: FlutterListView(
        reverse: true,//
        delegate: FlutterListViewDelegate(
        (BuildContext context, int index) {
      return Container(
        margin: EdgeInsets.symmetric(horizontal: 20, vertical: 5),
        decoration: BoxDecoration(
          borderRadius: BorderRadius.circular(8),
          color: Color(0xFF333333),
        ),
        height: 100,
        child: Builder(
          builder: (BuildContext context) {
            return GestureDetector(
              onTap: () {
                try{
                  var box = context.findRenderObject() as RenderBox;
                  final Offset offset = box.localToGlobal(Offset.zero);
                  var size = box.size;
                  Get.to(Material(
                    color: Colors.transparent,
                    child: Stack(
                      children: [
                        Positioned(
                          left: offset.dx,
                          top: offset.dy,
                          child: Container(
                            color: Colors.yellow,
                            width: size.width,
                            height: size.height,
                          ),
                        )
                      ],
                    ),
                  ));
                }catch(e){
                  print(e);
                }
              },
            );
          },
        ),
      );},
          childCount: 5,
          firstItemAlign: FirstItemAlign.end, //for sure the list is aligning top
        ),
      ),
    );

opened by Iridescentangle 6

[cacheExtent] is ineffective

Hi! Thanks for your great work, but i'm stuck in setting cacheExtent.

Example code:

class HomePage extends StatelessWidget {

  @override
  Widget build(BuildContext context) {
    return FlutterListView(
      cacheExtent: 500,
      delegate: FlutterListViewDelegate(
        (context, index) {
          print(index);
          return Container(color: Colors.red, height: 50);
        },
        childCount: 500,
        onItemKey: (index) => index.toString(),
        onItemHeight: (index) => 50,
      ),
    );
  }
}

For my device, enter this page will get index outputs 1 to 34. But if i change cacheExtent to another value(no matter what its value is), the outputs is always same(1 to 34). I wonder if there's any mistake in my code?

opened by jiangtian616 4

boundcing scroll offset

预期: 下拉回弹会定位到顶部第一个元素. 但是现在会回弹至第2,3个元素才停止

expect: bouncing and stop edge first item

----screen top edge-----
------  <-- expect stop position
-------
------- <-- current version stop scroll offset
-------
-------


class BingoPage extends StatefulWidget {
  @override
  State<BingoPage> createState() => _BingoPageState();
}

class _BingoPageState extends State<BingoPage> {
  final logic = Get.find<BingoLogic>();

  final data = <String>[];

  @override
  void initState() {
    // mock chat list insert data
    Timer.periodic(Duration(seconds: 1), (timer) {
      setState(() {
        data.insert(0, DateTime.now().toString());
      });
    });
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        body: FlutterListView(
            reverse: true,
            delegate: FlutterListViewDelegate(
              (BuildContext context, int index) => ListTile(title: Text('List Item ${data[index]}')),
              childCount: data.length,
              keepPosition: true,
            )));
  }
}

opened by qyu37 4

PopupMenuButton doesn't work

I'm trying to integrate PopupMenuButton with FlutterListView but it doesn't show menu buttons when I click on more_vertical icon.

FlutterListView(
                  controller: ctl.listViewController,
                  delegate: FlutterListViewDelegate((context, index) {
                    return ListTile(
                      title: Text('index: $index'),
                      trailing: PopupMenuButton<String>(
                        key: ValueKey(index),
                        offset: const Offset(0, 8),
                        child: const Icon(Icons.more_vert),
                        itemBuilder: (context) {
                          return const [
                            PopupMenuItem(
                              value: 'edit',
                              child: Text('Edit'),
                            ),
                            PopupMenuItem(
                              value: 'delete',
                              child: Text('Delete'),
                            )
                          ];
                        },
                        onSelected: (val) {
                          Fluttertoast.showToast(msg: val);
                        },
                      ),
                    );

2022-03-24 18 31 13

After clicking on more_vertical icon It show these errors:

══╡ EXCEPTION CAUGHT BY SCHEDULER LIBRARY ╞═════════
The following assertion was thrown during a scheduler callback:
Offset argument contained a NaN value.
'dart:ui/painting.dart':
Failed assertion: line 43 pos 10: '<optimized out>'

Either the assertion indicates an error in the framework itself, or we should provide substantially
more information in this error message to help you determine and fix the underlying cause.
In either case, please report this assertion by filing a bug on GitHub:
  https://github.com/flutter/flutter/issues/new?template=2_bug.md

When the exception was thrown, this was the stack:
#2      _offsetIsValid (dart:ui/painting.dart:43:10)
#3      Path.contains (dart:ui/painting.dart:2557:12)
#4      PhysicalModelLayer.findAnnotations (package:flutter/src/rendering/layer.dart:2055:20)
#5      ContainerLayer.findAnnotations (package:flutter/src/rendering/layer.dart:986:37)
#6      OffsetLayer.findAnnotations (package:flutter/src/rendering/layer.dart:1217:18)
#7      ContainerLayer.findAnnotations (package:flutter/src/rendering/layer.dart:986:37)
#8      OffsetLayer.findAnnotations (package:flutter/src/rendering/layer.dart:1217:18)
#9      ContainerLayer.findAnnotations (package:flutter/src/rendering/layer.dart:986:37)
#10     OffsetLayer.findAnnotations (package:flutter/src/rendering/layer.dart:1217:18)
#11     ContainerLayer.findAnnotations (package:flutter/src/rendering/layer.dart:986:37)
#12     OffsetLayer.findAnnotations (package:flutter/src/rendering/layer.dart:1217:18)
#13     TransformLayer.findAnnotations (package:flutter/src/rendering/layer.dart:1702:18)
#14     Layer.find (package:flutter/src/rendering/layer.dart:494:5)
#15     RenderView._updateSystemChrome (package:flutter/src/rendering/view.dart:287:60)
#16     RenderView.compositeFrame (package:flutter/src/rendering/view.dart:230:9)
#17     RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:501:18)
#18     WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:883:13)
#19     RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:363:5)
#20     SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1144:15)
#21     SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1081:9)
#22     SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:995:5)
#26     _invoke (dart:ui/hooks.dart:151:10)
#27     PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:308:5)
#28     _drawFrame (dart:ui/hooks.dart:115:31)
(elided 5 frames from class _AssertionError and dart:async)

Doctor summery

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 2.10.4, on macOS 12.2 21D49 darwin-x64, locale en-KH)
[✓] Android toolchain - develop for Android devices (Android SDK version 32.1.0-rc1)
[✓] Xcode - develop for iOS and macOS (Xcode 13.2.1)
[✓] Android Studio (version 2021.1)
[✓] VS Code (version 1.65.2)
[✓] Connected device (1 available)
[✓] HTTP Host Availability

• No issues found!

opened by serey168 2

Deleted items still wisible by tester

I faced with issue when I remove items from FlutterListView they still visible by tester.

You can reproduce this problem by runing test in this project https://github.com/krida2000/flutter_list_view_problem.

This problem fixed by uncoment this code:

Can wee just uncoment this code or there is a better solution?

opened by krida2000 1

exception about lastDetails is DragStartDetails is not true

thanks for your awesome work. when use get some exception:


flutter:   ERROR   ERROR │ ⛔ ══╡ EXCEPTION CAUGHT BY SCHEDULER LIBRARY ╞══════════════════════
flutter:   ERROR   ERROR │ ⛔ The following assertion was thrown during a scheduler callback:
flutter:   ERROR   ERROR │ ⛔ 'package:flutter/src/widgets/scroll_activity.dart': Failed
flutter:   ERROR   ERROR │ ⛔ assertion: line 457 pos 12: 'lastDetails is DragStartDetails': is
flutter:   ERROR   ERROR │ ⛔ not true.


flutter:   ERROR   ERROR │ ⛔ When the exception was thrown, this was the stack:
flutter:   ERROR   ERROR │ ⛔ #2      DragScrollActivity.dispatchScrollStartNotification (package:flutter/src/widgets/scroll_activity.dart:457:12)
flutter:   ERROR   ERROR │ ⛔ #3      ScrollPosition.didStartScroll (package:flutter/src/widgets/scroll_position.dart:895:15)
flutter:   ERROR   ERROR │ ⛔ #4      FlutterListViewElement.notifyPositionChanged.<anonymous closure> (package:flutter_list_view/src/flutter_list_view_element.dart:188:17)
flutter:   ERROR   ERROR │ ⛔ #5      SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1144:15)
flutter:   ERROR   ERROR │ ⛔ #6      SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1089:9)
flutter:   ERROR   ERROR │ ⛔ #7      SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:995:5)
flutter:   ERROR   ERROR │ ⛔ #11     _invoke (dart:ui/hooks.dart:151:10)
flutter:   ERROR   ERROR │ ⛔ #12     PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:308:5)
flutter:   ERROR   ERROR │ ⛔ #13     _drawFrame (dart:ui/hooks.dart:115:31)
flutter:   ERROR   ERROR │ ⛔ (elided 5 frames from class _AssertionError and dart:async)
flutter:   ERROR   ERROR │ ⛔ ═════════════════════════════════════════════════════════════════

opened by qyu37 1

Assertion 'child.parent == this': is not true

尝试在项目中引入flutter_list_view用来展示消息列表，展示正常，但是下拉加载历史消息时（因为消息列表是反转的)抛出异常

======== Exception caught by rendering library =====================================================
The following assertion was thrown during performLayout():
RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout().
'package:flutter/src/rendering/box.dart':
Failed assertion: line 1938 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout ||
              (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'


Either the assertion indicates an error in the framework itself, or we should provide substantially more information in this error message to help you determine and fix the underlying cause.
In either case, please report this assertion by filing a bug on GitHub:
  https://github.com/flutter/flutter/issues/new?template=2_bug.md

The relevant error-causing widget was: 
  FlutterSliverList file:///Users/xx/Documents/workspace/xx/flutter_list_view/lib/src/flutter_list_view.dart:161:7
When the exception was thrown, this was the stack: 
#2      RenderBox.size.<anonymous closure> (package:flutter/src/rendering/box.dart:1938:13)
#3      RenderBox.size (package:flutter/src/rendering/box.dart:1951:6)
#4      FlutterListViewRender.performLayout (package:flutter_list_view/src/flutter_list_view_render.dart:213:30)
#5      RenderObject.layout (package:flutter/src/rendering/object.dart:1779:7)
#6      RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:510:13)
...
The following RenderObject was being processed when the exception was fired: FlutterListViewRender#7574b relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-COMPOSITING-BITS-UPDATE
...  needs compositing
...  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
...  constraints: SliverConstraints(AxisDirection.up, GrowthDirection.forward, ScrollDirection.reverse, scrollOffset: 825.5, remainingPaintExtent: 718.0, crossAxisExtent: 432.0, crossAxisDirection: AxisDirection.right, viewportMainAxisExtent: 718.0, remainingCacheExtent: 1218.0, cacheOrigin: -250.0)
...  geometry: SliverGeometry(scrollExtent: 1922.1, paintExtent: 718.0, maxPaintExtent: 718.0, hasVisualOverflow: true, cacheExtent: 1218.0)
...    scrollExtent: 1922.1
...    paintExtent: 718.0
...    maxPaintExtent: 718.0
...    hasVisualOverflow: true
...    cacheExtent: 1218.0
RenderObject: FlutterListViewRender#7574b relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-COMPOSITING-BITS-UPDATE
  needs compositing
  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
  constraints: SliverConstraints(AxisDirection.up, GrowthDirection.forward, ScrollDirection.reverse, scrollOffset: 825.5, remainingPaintExtent: 718.0, crossAxisExtent: 432.0, crossAxisDirection: AxisDirection.right, viewportMainAxisExtent: 718.0, remainingCacheExtent: 1218.0, cacheOrigin: -250.0)
  geometry: SliverGeometry(scrollExtent: 1922.1, paintExtent: 718.0, maxPaintExtent: 718.0, hasVisualOverflow: true, cacheExtent: 1218.0)
    scrollExtent: 1922.1
    paintExtent: 718.0
    maxPaintExtent: 718.0
    hasVisualOverflow: true
    cacheExtent: 1218.0
====================================================================================================


======== Exception caught by rendering library =====================================================
The following assertion was thrown during paint():
'package:flutter_list_view/src/flutter_list_view_render.dart': Failed assertion: line 844 pos 12: 'child.parent == this': is not true.

The relevant error-causing widget was: 
  FlutterSliverList file:///Users/xx/Documents/workspace/xx/flutter_list_view/lib/src/flutter_list_view.dart:161:7
When the exception was thrown, this was the stack: 
#2      FlutterListViewRender.childScrollOffset (package:flutter_list_view/src/flutter_list_view_render.dart:844:12)
#3      FlutterListViewRender.childMainAxisPosition (package:flutter_list_view/src/flutter_list_view_render.dart:838:14)
#4      FlutterListViewRender.paint (package:flutter_list_view/src/flutter_list_view_render.dart:680:36)
#5      RenderObject._paintWithContext (package:flutter/src/rendering/object.dart:2317:7)
#6      PaintingContext.paintChild (package:flutter/src/rendering/object.dart:187:13)
...
The following RenderObject was being processed when the exception was fired: FlutterListViewRender#7574b relayoutBoundary=up1
...  needs compositing
...  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
...  constraints: SliverConstraints(AxisDirection.up, GrowthDirection.forward, ScrollDirection.reverse, scrollOffset: 825.5, remainingPaintExtent: 718.0, crossAxisExtent: 432.0, crossAxisDirection: AxisDirection.right, viewportMainAxisExtent: 718.0, remainingCacheExtent: 1218.0, cacheOrigin: -250.0)
...  geometry: SliverGeometry(scrollExtent: 1922.1, paintExtent: 718.0, maxPaintExtent: 718.0, hasVisualOverflow: true, cacheExtent: 1218.0)
...    scrollExtent: 1922.1
...    paintExtent: 718.0
...    maxPaintExtent: 718.0
...    hasVisualOverflow: true
...    cacheExtent: 1218.0
RenderObject: FlutterListViewRender#7574b relayoutBoundary=up1
  needs compositing
  parentData: paintOffset=Offset(0.0, 0.0) (can use size)
  constraints: SliverConstraints(AxisDirection.up, GrowthDirection.forward, ScrollDirection.reverse, scrollOffset: 825.5, remainingPaintExtent: 718.0, crossAxisExtent: 432.0, crossAxisDirection: AxisDirection.right, viewportMainAxisExtent: 718.0, remainingCacheExtent: 1218.0, cacheOrigin: -250.0)
  geometry: SliverGeometry(scrollExtent: 1922.1, paintExtent: 718.0, maxPaintExtent: 718.0, hasVisualOverflow: true, cacheExtent: 1218.0)
    scrollExtent: 1922.1
    paintExtent: 718.0
    maxPaintExtent: 718.0
    hasVisualOverflow: true
    cacheExtent: 1218.0
====================================================================================================

opened by Iridescentangle 0

Uncorrect `animateToIndex` animation

If call animateToIndex to element in end of the list, then animation will be uncorrect.

Problem

https://user-images.githubusercontent.com/71345244/209559725-76ba3cbf-fff7-4798-9b6d-50dfbae38655.mp4

I have fixed it by folowing changes:

Fix

opened by krida2000 3

ensureVisible issue,the offset need to increase scrollOffset

@@ -205,10 +205,11 @@ class FlutterListViewElement extends RenderObjectElement {
    // paintedElements
    var flutterListViewRender = renderObject as FlutterListViewRender;
    var viewportHeight = flutterListViewRender.currentViewportHeight ?? 0;
+   var scrollOffset = flutterListViewRender.currentScrollOffset ?? 0.0;
    for (var item in flutterListViewRender.paintedElements) {
      if (item.index == index &&
          item.offset > 0 &&
-          item.offset + item.height < viewportHeight) {
+          item.offset + item.height <= viewportHeight + scrollOffset) {
        return;
      }
    }

opened by huage2580 1

我有一个问题listview在快速滚动时异常 I have a problem that the listview is abnormal when scrolling quickly

er: │ 'package:flutter/src/widgets/framework.dart': Failed assertion: line 2535 pos 20: '_debugCurrentBuildTarget == context': is not true. flutter: │ flutter: │ #0 _AssertionError._doThrowNew (dart:core-patch/errors_patch.dart:47:61) flutter: │ #1 _AssertionError._throwNew (dart:core-patch/errors_patch.dart:36:5) flutter: │ #2 BuildOwner.buildScope. (package:flutter/src/widgets/framework.dart:2535:20) flutter: │ #3 BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2539:12) flutter: │ #4 FlutterListViewElement.updateChild (package:flutter_list_view/src/flutter_list_view_element.dart:605:12) flutter: │ #5 FlutterListViewElement._createOrReuseElement (package:flutter_list_view/src/flutter_list_view_element.dart:525:7) flutter: │ #6 FlutterListViewElement.constructNextElement (package:flutter_list_view/src/flutter_list_view_element.dart:566:18) flutter: │ #7 FlutterListViewRender.performLayout. (package:flutter_list_view/src/flutter_list_view_render.dart:206:34) flutter: │ #8 RenderObject.invokeLayoutCallback. (package:flutter/src/rendering/object.dart:1962:59) flutter: │ #9 PipelineOwner._enableMutationsToDirtySubtrees (package:flutter/src/rendering/object.dart:910:15) flutter: │ #10 RenderObject.invokeLayoutCallback (package:flutter/src/rendering/object.dart:1962:14) flutter: │ #11 FlutterListViewRender.performLayout (package:flutter_list_view/src/flutter_list_view_render.dart:205:7) flutter: │ #12 RenderObject.layout (package:flutter/src/rendering/object.dart:1852:7) flutter: │ #13 RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:510:13) flutter: │ #14 RenderViewport._attemptLayout (package:flutter/src/rendering/viewport.dart:1580:12) flutter: │ #15 RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:1489:20) flutter: │ #16 RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1707:7) flutter: │ #17 PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:879:18) flutter: │ #18 RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:497:19) flutter: │ #19 WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:883:13) flutter: │ #20 RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:363:5) flutter: │ #21 SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1145:15) flutter: │ #22 SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1082:9) flutter: │ #23 SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:996:5) flutter: │ #24 _rootRun (dart:async/zone.dart:1428:13) flutter: │ #25 _CustomZone.run (dart:async/zone.dart:1328:19) flutter: │ #26 _CustomZone.runGuarded (dart:async/zone.dart:1236:7) flutter: │ #27 _invoke (dart:ui/hooks.dart:150:10) flutter: │ #28 PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:270:5) flutter: │ #29 _drawFrame (dart:ui/hooks.dart:114:31)

opened by fengyuyxz 0
I have a problem with chat view, help please

first, very thanks for this project, I try to implement chat view, and load message from the top down, but I failure, some problems always occur with me. I use your project and implement chat functional basically. but when I create a new chat view, and send message one by one, the chat view always has a brief flicker and the animation is not very smooth, I don't known how to config can avoid this problem, help me please.

opened by endison1986 8

Touch position are incorrect

Hi, The touch position of the item is incorrect,when items not out of page.

edit in your chat example :

import 'dart:math';
import 'dart:ui';

import 'package:flutter/cupertino.dart';
import 'package:flutter_list_view/flutter_list_view.dart';
import 'package:flutter/material.dart';
import 'package:pull_to_refresh/pull_to_refresh.dart';

enum MessageType {
  sent,
  receive,
  tag,
}

class ChatModel {
  ChatModel({required this.id, required this.msg, required this.type});

  int id;
  String msg;
  MessageType type;
}

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

  @override
  _ChatState createState() => _ChatState();
}

class _ChatState extends State<Chat> {
  int currentId = 0;
  List<ChatModel> messages = [];
  final myController = TextEditingController();
  final listViewController = FlutterListViewController();
  final refreshController = RefreshController(initialRefresh: false);

  /// Using init index to control load first messages
  int initIndex = 0;
  double initOffset = 0.0;
  bool initOffsetBasedOnBottom = true;
  int forceToExecuteInitIndex = 0;

  // Fire refresh temp variable
  double prevScrollOffset = 0;

  List<FlutterListViewItemPosition>? itemPositions;
  double listviewHeight = 0;

  @override
  void initState() {
    _loadMessages();
    listViewController.addListener(() {
      const torrentDistance = 40;
      var offset = listViewController.offset;
      if (offset <= torrentDistance && prevScrollOffset > torrentDistance) {
        if (!refreshController.isRefresh) {
          refreshController.requestRefresh();
        }
      }

      prevScrollOffset = offset;
    });

    listViewController.sliverController.onPaintItemPositionsCallback = (widgetHeight, positions) {
      itemPositions = positions;
      listviewHeight = widgetHeight;
    };

    super.initState();
  }

  /// It is mockup to load messages from server
  _loadMessages() async {
    await Future.delayed(const Duration(milliseconds: 100));
    var prevTimes = Random().nextInt(20) + 1;
    // for (var i = 0; i < prevTimes; i++) {
    //   _insertReceiveMessage("The demo also show how to reverse a list in\r\n" *
    //       (Random().nextInt(4) + 1));
    // }
    _insertTagMessage("Last readed");
    var nextTimes = Random().nextInt(20) + 1;
    // for (var i = 0; i < nextTimes; i++) {
    //   _insertReceiveMessage("The demo also show how to reverse a list in\r\n" *
    //       (Random().nextInt(4) + 1));
    // }
    _insertSendMessage("If message more than two screens and scroll over 80px, the scroll not move if a message coming or you input a message");
    _insertSendMessage("It resoved the problem which is when you read a message while a lot of messages coming");
    _insertSendMessage("You can't focus the message content what you read");
    _insertSendMessage("The demo also show how to reverse a list in the controll");
    _insertSendMessage("When reverse the list, the item still show on top of list if the messages didn't fill full screen");

    initIndex = messages.length - prevTimes - 1;
    print("--------------------$initIndex");

    setState(() {});
  }

  _insertSendMessage(String msg, {bool appendToTailer = false}) {
    if (appendToTailer) {
      messages.add(ChatModel(id: ++currentId, msg: msg.trim(), type: MessageType.sent));
    } else {
      messages.insert(0, ChatModel(id: ++currentId, msg: msg.trim(), type: MessageType.sent));
    }
  }

  _insertReceiveMessage(String msg, {bool appendToTailer = false}) {
    if (appendToTailer) {
      messages.add(ChatModel(id: ++currentId, msg: msg.trim(), type: MessageType.receive));
    } else {
      messages.insert(0, ChatModel(id: ++currentId, msg: msg.trim(), type: MessageType.receive));
    }
  }

  _insertTagMessage(String msg) {
    messages.insert(0, ChatModel(id: ++currentId, msg: msg.trim(), type: MessageType.tag));
  }

  _mockToReceiveMessage() {
    var times = Random().nextInt(4) + 1;
    for (var i = 0; i < times; i++) {
      _insertReceiveMessage("The demo also show how to reverse a list in\r\n" * (Random().nextInt(4) + 1));
    }
    setState(() {});
  }

  _sendMessage() {
    if (myController.text.isNotEmpty) {
      if (messages.isNotEmpty) {
        listViewController.sliverController.jumpToIndex(0);
      }
      setState(() {
        _insertSendMessage(myController.text);
      });

      myController.text = "";
    }
  }

  void _onRefresh() async {
    print("------------------------------------_onRefresh");
    await Future.delayed(const Duration(milliseconds: 2000));

    var newMessgeLength = 20;

    for (var i = 0; i < newMessgeLength; i++) {
      _insertReceiveMessage("The demo also show how to reverse a list in\r\n" * (Random().nextInt(4) + 1));
    }

    var firstIndex = newMessgeLength;
    var firstOffset = 0.0;
    if (itemPositions != null && itemPositions!.isNotEmpty) {
      var firstItemPosition = itemPositions![0];
      firstIndex = firstItemPosition.index + newMessgeLength;
      firstOffset = listviewHeight - firstItemPosition.offset - firstItemPosition.height;
    }

    initIndex = firstIndex;
    initOffsetBasedOnBottom = false;
    forceToExecuteInitIndex++;
    initOffset = firstOffset;
    refreshController.refreshCompleted();
    setState(() {});
  }

  void _onLoading() async {
    await Future.delayed(const Duration(milliseconds: 1000));

    for (var i = 0; i < 50; i++) {
      _insertReceiveMessage("The demo also show how to append message\r\n" * (Random().nextInt(4) + 1), appendToTailer: true);
    }

    if (mounted) setState(() {});
    refreshController.loadComplete();
  }

  _renderItem(int index) {
    var msg = messages[index];
    if (msg.type == MessageType.tag) {
      return Align(
        alignment: Alignment.center,
        child: Padding(
          padding: const EdgeInsets.all(10.0),
          child: Container(
            decoration: const BoxDecoration(color: Colors.grey, borderRadius: BorderRadius.all(Radius.circular(5))),
            child: Padding(
              padding: const EdgeInsets.all(10.0),
              child: Text(
                msg.msg,
                style: const TextStyle(fontSize: 14.0, color: Colors.white),
              ),
            ),
          ),
        ),
      );
    } else {
      return Align(
        alignment: msg.type == MessageType.sent ? Alignment.centerRight : Alignment.centerLeft,
        child: Padding(
          padding: const EdgeInsets.all(10.0),
          child: GestureDetector(
            onTap: () {
              print(msg.msg);
            },
            child: Container(
              decoration: BoxDecoration(
                  color: msg.type == MessageType.sent ? Colors.blue : Colors.green,
                  borderRadius: msg.type == MessageType.sent
                      ? const BorderRadius.only(topLeft: Radius.circular(20), bottomLeft: Radius.circular(20), bottomRight: Radius.circular(20))
                      : const BorderRadius.only(topRight: Radius.circular(20), bottomLeft: Radius.circular(20), bottomRight: Radius.circular(20))),
              child: Padding(
                padding: const EdgeInsets.all(10.0),
                child: Text(
                  msg.msg,
                  style: const TextStyle(fontSize: 14.0, color: Colors.white),
                ),
              ),
            ),
          ),
        ),
      );
    }
  }

  _renderList() {
    return ScrollConfiguration(
      behavior: ScrollConfiguration.of(context).copyWith(dragDevices: {
        PointerDeviceKind.touch,
        PointerDeviceKind.mouse,
      }),
      child: SmartRefresher(
          enablePullDown: false,
          enablePullUp: false,
          header: CustomHeader(
            completeDuration: const Duration(milliseconds: 0),
            builder: (context, mode) {
              Widget body;
              if (mode == RefreshStatus.idle) {
                body = const Text("Pull up load prev msg");
              } else if (mode == RefreshStatus.refreshing) {
                body = const CupertinoActivityIndicator();
              } else if (mode == RefreshStatus.failed) {
                body = const Text("Load Failed!Click retry!");
              } else if (mode == RefreshStatus.canRefresh) {
                body = const Text("Release to load more");
              } else {
                body = const Text("No more Data");
              }
              if (mode == RefreshStatus.completed) {
                return Container();
              } else {
                return RotatedBox(
                  quarterTurns: 2,
                  child: SizedBox(
                    height: 55.0,
                    child: Center(child: body),
                  ),
                );
              }
            },
          ),
          // const WaterDropHeader(),
          footer: CustomFooter(
            builder: (context, mode) {
              Widget body;
              if (mode == LoadStatus.idle) {
                body = const Text("Pull down to load more message");
              } else if (mode == LoadStatus.loading) {
                body = const CupertinoActivityIndicator();
              } else if (mode == LoadStatus.failed) {
                body = const Text("Load Failed!Click retry!");
              } else if (mode == LoadStatus.canLoading) {
                body = const Text("Release to load more");
              } else {
                body = const Text("No more Data");
              }
              return SizedBox(
                height: 55.0,
                child: Center(child: body),
              );
            },
          ),
          controller: refreshController,
          onRefresh: _onRefresh,
          onLoading: _onLoading,
          child: FlutterListView(
              reverse: true,
              controller: listViewController,
              delegate: FlutterListViewDelegate((BuildContext context, int index) => _renderItem(index),
                  childCount: messages.length,
                  onItemKey: (index) => messages[index].id.toString(),
                  keepPosition: true,
                  keepPositionOffset: 40,
                  initIndex: initIndex,
                  initOffset: initOffset,
                  initOffsetBasedOnBottom: initOffsetBasedOnBottom,
                  forceToExecuteInitIndex: forceToExecuteInitIndex,
                  firstItemAlign: FirstItemAlign.end))),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: const Text("Chat"),
          actions: [
            TextButton(
                onPressed: _mockToReceiveMessage,
                child: const Text(
                  "Mock To Receive",
                  style: TextStyle(color: Colors.white),
                ))
          ],
        ),
        resizeToAvoidBottomInset: true,
        body: GestureDetector(
            onTap: () {
              FocusScopeNode currentFocus = FocusScope.of(context);
              if (!currentFocus.hasPrimaryFocus) {
                currentFocus.unfocus();
              }
            },
            behavior: HitTestBehavior.opaque,
            child: SafeArea(
              child: Padding(
                padding: const EdgeInsets.only(bottom: 8.0),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.stretch,
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    Expanded(flex: 1, child: _renderList()),
                    Padding(
                      padding: const EdgeInsets.symmetric(horizontal: 20.0),
                      child: Row(children: [
                        Expanded(
                          child: TextField(
                            controller: myController,
                          ),
                        ),
                        ElevatedButton(onPressed: _sendMessage, child: const Text("Send"))
                      ]),
                    )
                  ],
                ),
              ),
            )));
  }

  @override
  void dispose() {
    myController.dispose();
    listViewController.dispose();
    refreshController.dispose();
    super.dispose();
  }
}

opened by HuangZiquan 2

Activate the keyboard, then manually scroll down the list to the bottom, and then lose the keyboard, as if it would appear

════════ Exception caught by rendering library ═════════════════════════════════ RenderIndexedSemantics does not meet its constraints. The relevant error-causing widget was FlutterSliverList ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ Invalid argument(s): 0.0 The relevant error-causing widget was SmartRefresher ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ BoxConstraints has non-normalized width constraints. The relevant error-causing widget was Container ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ BoxConstraints has non-normalized width constraints. The relevant error-causing widget was Container ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ BoxConstraints has both width and height constraints non-normalized. The relevant error-causing widget was Column ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ BoxConstraints has both width and height constraints non-normalized. The relevant error-causing widget was GestureDetector ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ BoxConstraints has both width and height constraints non-normalized. The relevant error-causing widget was GestureDetector ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by scheduler library ═════════════════════════════════ 'package:flutter/src/semantics/semantics.dart': Failed assertion: line 3995 pos 12: 'value != null && value >= 0.0': is not true. ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by scheduler library ═════════════════════════════════ 'package:flutter/src/animation/animation_controller.dart': Failed assertion: line 822 pos 12: 'elapsedInSeconds >= 0.0': is not true. ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════ flutter: (at_bottom_tab.dart line：159): bottomTab dispose 840232081

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#205b3 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/rendering/object.dart': Failed assertion: line 1601 pos 12: '_debugCanPerformMutations': is not true. ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#bb69f parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#6ff6b parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#ec916 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#6bdd9 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#027b9 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#34c80 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#dcd0f parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#5401c parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#0947a parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#6d344 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#9bbb1 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#2c4d7 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by widgets library ═══════════════════════════════════ 'package:flutter/src/material/button_theme.dart': Failed assertion: line 219 pos 15: 'minWidth != null && minWidth >= 0.0': is not true. The relevant error-causing widget was MaterialApp ════════════════════════════════════════════════════════════════════════════════

════════ Exception caught by rendering library ═════════════════════════════════ RenderBox.size accessed beyond the scope of resize, layout, or permitted parent access. RenderBox can always access its own size, otherwise, the only object that is allowed to read RenderBox.size is its parent, if they have said they will. It you hit this assert trying to access a child's size, pass "parentUsesSize: true" to that child's layout(). 'package:flutter/src/rendering/box.dart': Failed assertion: line 1935 pos 13: 'debugDoingThisResize || debugDoingThisLayout || _computingThisDryLayout || (RenderObject.debugActiveLayout == parent && _size._canBeUsedByParent)'

The relevant error-causing widget was MaterialApp The following RenderObject was being processed when the exception was fired: RenderCustomPaint#5e339 RenderObject: RenderCustomPaint#5e339 parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) child: RenderErrorBox#3ff2b parentData: (can use size) constraints: BoxConstraints(w=428.0, h=926.0) size: Size(428.0, 926.0) ════════════════════════════════════════════════════════════════════════════════

opened by fujiekai 4