使用get控制器刷新时，第一次下拉刷新由空视图到列表会报错，不影响使用。上拉加载不会报错

[chjsun]

Obx(()=> EasyRefresh(
        onRefresh: () {
          controller.onRefreshList(sign);
        },
        onLoad: () {
          controller.onLoadList(sign);
        },
        controller: controller.refreshController,
        child: ListView.builder(
          itemCount: data.isEmpty ? 1 : data.length,
          itemBuilder: (BuildContext context, int position) {
            if (data.isEmpty) {
              return const NoDataView();
            }
            ElectronicOrderListModel model = data[position];
            return ElectronicOrderListCell(
                model: model,
                onClick: () {
                  Get.toNamed(OldRoutes.ElecContractorListPage, arguments: model)?.then((value) {
                    /// 刷新列表
                    controller.onSearchList();
                  });
                });
          },
        ))
)

ERROR：

======== Exception caught by foundation library ====================================================
The following assertion was thrown while dispatching notifications for FooterNotifier:
Build scheduled during frame.

While the widget tree was being built, laid out, and painted, a new frame was scheduled to rebuild the widget tree.

This might be because setState() was called from a layout or paint callback. If a change is needed to the widget tree, it should be applied as the tree is being built. Scheduling a change for the subsequent frame instead results in an interface that lags behind by one frame. If this was done to make your build dependent on a size measured at layout time, consider using a LayoutBuilder, CustomSingleChildLayout, or CustomMultiChildLayout. If, on the other hand, the one frame delay is the desired effect, for example because this is an animation, consider scheduling the frame in a post-frame callback using SchedulerBinding.addPostFrameCallback or using an AnimationController to trigger the animation.

When the exception was thrown, this was the stack: 
#0      WidgetsBinding._handleBuildScheduled.<anonymous closure> (package:flutter/src/widgets/binding.dart:756:9)
#1      WidgetsBinding._handleBuildScheduled (package:flutter/src/widgets/binding.dart:779:6)
#2      BuildOwner.scheduleBuildFor (package:flutter/src/widgets/framework.dart:2482:24)
#3      Element.markNeedsBuild (package:flutter/src/widgets/framework.dart:4495:12)
#4      State.setState (package:flutter/src/widgets/framework.dart:1129:15)
#5      _ValueListenableBuilderState._valueChanged (package:flutter/src/widgets/value_listenable_builder.dart:182:5)
#6      _IndicatorListenable._onNotify (package:easy_refresh/src/notifier/indicator_notifier.dart:762:15)
#7      ChangeNotifier.notifyListeners (package:flutter/src/foundation/change_notifier.dart:324:24)
#8      IndicatorNotifier._updateOffset (package:easy_refresh/src/notifier/indicator_notifier.dart:473:9)
#9      IndicatorNotifier._updateBySimulation (package:easy_refresh/src/notifier/indicator_notifier.dart:427:5)
#10     _ERScrollPhysics.createBallisticSimulation (package:easy_refresh/src/physics/scroll_physics.dart:361:20)
#11     ScrollPhysics.createBallisticSimulation (package:flutter/src/widgets/scroll_physics.dart:343:20)
#12     ScrollPositionWithSingleContext.goBallistic (package:flutter/src/widgets/scroll_position_with_single_context.dart:144:44)
#13     IdleScrollActivity.applyNewDimensions (package:flutter/src/widgets/scroll_activity.dart:157:14)
#14     ScrollPosition.applyNewDimensions (package:flutter/src/widgets/scroll_position.dart:623:15)
#15     ScrollPositionWithSingleContext.applyNewDimensions (package:flutter/src/widgets/scroll_position_with_single_context.dart:104:11)
#16     ScrollPosition.applyContentDimensions (package:flutter/src/widgets/scroll_position.dart:553:7)
#17     RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:1493:20)
#18     RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1757:7)
#19     PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:887:18)
#20     RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:504:19)
#21     WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:892:13)
#22     RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:370:5)
#23     SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1146:15)
#24     SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1083:9)
#25     SchedulerBinding._handleDrawFrame (package:flutter/src/scheduler/binding.dart:997:5)
#29     _invoke (dart:ui/hooks.dart:151:10)
#30     PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:308:5)
#31     _drawFrame (dart:ui/hooks.dart:115:31)
(elided 3 frames from dart:async)
The FooterNotifier sending notification was: Instance of 'FooterNotifier'
====================================================================================================

➜  ~ flutter doctor
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, 3.0.2, on macOS 12.4 21F79 darwin-arm, locale zh-Hans-CN)
[✓] Android toolchain - develop for Android devices (Android SDK version 33.0.0)
[✓] Xcode - develop for iOS and macOS (Xcode 13.4.1)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2021.2)
[✓] IntelliJ IDEA Community Edition (version 2022.1.4)
[✓] VS Code (version 1.69.2)
[✓] Connected device (3 available)
[✓] HTTP Host Availability

• No issues found!

[chjsun]

补充截图。然后问题出现后，footer就消失了。但是上拉加载功能还能触发。

[xuelongqy]

onRefresh和onLoad使用async和await试试看？