[Bug report] Looking up a deactivated widget's ancestor is unsafe.

[Rock-chan]

Version

4.1.2

Platforms

dart, Android, iOS

Device Model

iPhone X iOS16

flutter info

admin@admindeMacBook-Pro app % flutter doctor -v
[!] Flutter (Channel stable, 3.10.5, on macOS 12.6.6 21G646 darwin-x64, locale zh-Hans-CN)
    • Flutter version 3.10.5 on channel stable at /Users/admin/development/flutter
    ! Warning: `dart` on your path resolves to /usr/local/Cellar/dart/3.0.4/libexec/bin/dart, which is not inside your current Flutter SDK checkout at
      /Users/admin/development/flutter. Consider adding /Users/admin/development/flutter/bin to the front of your path.
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 796c8ef792 (7 weeks ago), 2023-06-13 15:51:02 -0700
    • Engine revision 45f6e00911
    • Dart version 3.0.5
    • DevTools version 2.23.1
    • Pub download mirror https://pub.flutter-io.cn
    • Flutter download mirror https://storage.flutter-io.cn
    • If those were intentional, you can disregard the above warnings; however it is recommended to use "git" directly to perform update checks and upgrades.

[✓] Android toolchain - develop for Android devices (Android SDK version 33.0.2)
    • Android SDK at /Users/admin/Library/Android/sdk
    • Platform android-33, build-tools 33.0.2
    • ANDROID_HOME = /Users/admin/Library/Android/sdk
    • Java binary at: /Applications/Android Studio.app/Contents/jre/Contents/Home/bin/java
    • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b802.4-9586694)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS (Xcode 14.2)
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Build 14C18
    • CocoaPods version 1.12.1

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[✓] Android Studio (version 2022.2)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    • Java version OpenJDK Runtime Environment (build 17.0.6+0-17.0.6b802.4-9586694)

[✓] VS Code (version 1.79.1)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.68.0

[✓] Connected device (3 available)
    • iPhone (4) (mobile) • 00008020-001C589A2203002E • ios            • iOS 16.3.1 20D67
    • macOS (desktop)     • macos                     • darwin-x64     • macOS 12.6.6 21G646 darwin-x64
    • Chrome (web)        • chrome                    • web-javascript • Google Chrome 115.0.5790.114

[!] Network resources             
    ✗ A network error occurred while checking "https://github.com/": Operation timed out

! Doctor found issues in 2 categories.

How to reproduce?

1、When you first go to the page which you use the widget, sometime it will show the error.
2、When you refresh your list, before the data getting, you hold the screen and then you will receive the error.

Logs

I/flutter ( 9284): Caught error: Looking up a deactivated widget's ancestor is unsafe.
I/flutter ( 9284): At this point the state of the widget's element tree is no longer stable.
I/flutter ( 9284): To safely refer to a widget's ancestor in its dispose() method, save a reference to the ancestor by calling dependOnInheritedWidgetOfExactType() in the widget's didChangeDependencies() method.
I/flutter ( 9284): Stack trace:
I/flutter ( 9284): package:flutter/src/widgets/framework.dart 4347:9 Element._debugCheckStateIsActiveForAncestorLookup.<fn>
I/flutter ( 9284): package:flutter/src/widgets/framework.dart 4361:6 Element._debugCheckStateIsActiveForAncestorLookup
I/flutter ( 9284): package:flutter/src/widgets/framework.dart 4396:12 Element.getElementForInheritedWidgetOfExactType
I/flutter ( 9284): package:flutter/src/widgets/inherited_model.dart 143:45 InheritedModel._findModels
I/flutter ( 9284): package:flutter/src/widgets/inherited_model.dart 191:5 InheritedModel.inheritFrom
I/flutter ( 9284): package:flutter/src/widgets/media_query.dart 1058:27 MediaQuery._maybeOf
I/flutter ( 9284): package:flutter/src/widgets/media_query.dart 1101:67 MediaQuery.maybeDevicePixelRatioOf
I/flutter ( 9284): package:flutter/src/widgets/scroll_position.dart 244:45 ScrollPosition.devicePixelRatio
I/flutter ( 9284): package:flutter/src/widgets/

Example code (optional)

No response

Contact

chenzhangjin@outlook.com

[zmtzawqlp]

把你写的loaddata 代码发出来

[Rock-chan]

[Rock-chan]

71_1690799163.mp4

[Rock-chan]

`import 'package:loading_more_list/loading_more_list.dart';

typedef LoadDataCallBack<C> = Future<C> Function(int offset);

typedef OnDataChangeListener<C> = void Function(List<C> data);

///
/// 数据源基类 封装上下拉刷新逻辑
///
class CustomLoadingMoreBase<T> extends LoadingMoreBase<T> {
  CustomLoadingMoreBase({required this.loadDataCallBack, this.pageSize = 10, this.onDataChangeListener});

  /// 加载数据的回调方法
  LoadDataCallBack loadDataCallBack;

  /// 数据变化的回调
  OnDataChangeListener? onDataChangeListener;

  /// 默认第一页
  int _offset = 1;

  /// 是否还有更多数据
  bool _hasMore = true;

  /// 默认一页10条数据
  int pageSize;

  @override
  bool get hasMore => _hasMore;

  @override
  Future<bool> refresh([bool clearBeforeRequest = false]) async {
    print('CustomLoadingMoreBase clearBeforeRequest=$clearBeforeRequest');
    _offset = 0;
    _hasMore = true;
    return super.refresh(clearBeforeRequest);
  }

  @override
  Future<bool> loadData([bool isloadMoreAction = false]) async {
    print('CustomLoadingMoreBase isloadMoreAction=$isloadMoreAction');
    bool isSuccess = false;
    bool hasError = false;
    var newOffset = _offset + 1;

    /// 集合数据
    List? list;
    try {
      var listData = await loadDataCallBack(newOffset);
      if (newOffset == 1) {
        clear();
      }

      /// 如果listData本身就是一个集合
      if (listData is List) {
        list = listData;
      } else {
        /// 否则看下集合数据是不是在dataList或logList字段里面
        late bool isInDataList, isInLogList;
        try {
          isInDataList = (listData?.dataList?.length ?? 0) > 0;
        } catch (e) {
          print('CustomLoadingMoreBase: is not InDataList');
        }

        if (isInDataList == true) {
          list = listData.dataList;
        } else {
          try {
            isInLogList = (listData?.logList?.length ?? 0) > 0;
          } catch (e) {
            print('CustomLoadingMoreBase: is not InLogList');
          }
          if (isInLogList == true) {
            list = listData.logList;
          }
        }
      }

      /// 操作集合数据
      if (list is List) {
        for (var item in list) {
          add(item);
        }
        _offset = newOffset;
        _hasMore = list.length >= pageSize;
      } else {
        _hasMore = false;
      }

      isSuccess = true;
    } catch (exception, stack) {
      hasError = true;
      print(exception);
      print(stack);
    }
    if (onDataChangeListener != null) {
      onDataChangeListener!(list ?? []);
    }
    return isloadMoreAction ? isSuccess : !hasError;
  }
}`

[zmtzawqlp]

有没有能运行的最小的demo

[Rock-chan]

loading_more_list_demo.zip

[zmtzawqlp]

没有重现你说的问题

When you refresh your list, before the data getting, you hold the screen and then you will receive the error. 你说的这个case 并没有在demo 中有所体现呢？

[chenyeju]

试了下好像能复现，在首次加载页面数据的时候点住并向上滑动持续点住屏幕就会出现，只有首次构建该页面时操作才出现

[Rock-chan]

对的，应该就是每一次构建这个组件的时候，当数据还未加载完毕时，然后点住上滑就发生报错

[zmtzawqlp]

重现不了，你再怎么拉，内部 有 isloading 属性，不会重复去请求的。请提供一个能够重现现象的 demo

[chenyeju]

他这个就可以呀，我版本是 3.10.6 。进入时按住屏幕慢慢滑动就会复现了

[chenyeju]

操作视频
https://github.com/fluttercandies/loading_more_list/assets/82429935/73f845ca-9382-4b8b-a83d-714597790f18

[Rock-chan]

大佬怎么样，复现出来了吗？

[zmtzawqlp]

没有

[Rock-chan]

7_1691394508.mp4

flutter版本3.10.6，你给的demo中complex->nestedScrollView这个demo中，tab2这个页面你在加载的时候就去上下滑动页面，就可以看到报错了。