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Когда я пытаюсь деформировать мой ListView внутри SingleChildScrollView. Я не хочу, чтобы мой listViewBuilder прокручивался отдельно. Вот почему это изменение физики и shrinkWarp (я не понимаю, почему это изменилось). Я хочу, чтобы два некролируемых ListView.builder прокручивались за один ход, возможно, путем обертывания его внутри SingleChildScrollView.

 ══╡ EXCEPTION CAUGHT BY RENDERING LIBRARY ╞═════════════════════════════════════════════════════════
The following assertion was thrown during performLayout():
RenderFlex children have non-zero flex but incoming height constraints are unbounded.
When a column is in a parent that does not provide a finite height constraint, for example if it is
in a vertical scrollable, it will try to shrink-wrap its children along the vertical axis. Setting a
flex on a child (e.g. using Expanded) indicates that the child is to expand to fill the remaining
space in the vertical direction.
These two directives are mutually exclusive. If a parent is to shrink-wrap its child, the child
cannot simultaneously expand to fit its parent.
Consider setting mainAxisSize to MainAxisSize.min and using FlexFit.loose fits for the flexible
children (using Flexible rather than Expanded). This will allow the flexible children to size
themselves to less than the infinite remaining space they would otherwise be forced to take, and
then will cause the RenderFlex to shrink-wrap the children rather than expanding to fit the maximum
constraints provided by the parent.
If this message did not help you determine the problem, consider using debugDumpRenderTree():
  https://flutter.dev/debugging/#rendering-layer
  http://api.flutter.dev/flutter/rendering/debugDumpRenderTree.html
The affected RenderFlex is:
  RenderFlex#bf474 relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE(creator: Column ← _SingleChildViewport ← IgnorePointer-[GlobalKey#a96e8] ← Semantics ← _PointerListener ← Listener ← _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#2d1ee] ← _PointerListener ← Listener ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#be83e] ← ⋯, parentData: <none> (can use size), constraints: BoxConstraints(w=360.0, 0.0<=h<=Infinity), size: MISSING, direction: vertical, mainAxisAlignment: start, mainAxisSize: max, crossAxisAlignment: center, verticalDirection: down)
The creator information is set to:
  Column ← _SingleChildViewport ← IgnorePointer-[GlobalKey#a96e8] ← Semantics ← _PointerListener ←
  Listener ← _GestureSemantics ←
  RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#2d1ee] ← _PointerListener ← Listener
  ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#be83e] ← ⋯
The nearest ancestor providing an unbounded width constraint is: _RenderSingleChildViewport#7d98f NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE:
  needs compositing
  creator: _SingleChildViewport ← IgnorePointer-[GlobalKey#a96e8] ← Semantics ← _PointerListener ←
    Listener ← _GestureSemantics ←
    RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#2d1ee] ← _PointerListener ← Listener
    ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#be83e] ← RepaintBoundary ← ⋯
  parentData: <none> (can use size)
  constraints: BoxConstraints(w=360.0, h=471.0)
  size: MISSING
See also: https://flutter.dev/layout/
If none of the above helps enough to fix this problem, please don't hesitate to file a bug:
  https://github.com/flutter/flutter/issues/new?template=BUG.md

The relevant error-causing widget was:
  Column file:///D:/Other/App/Flutter/flash/lib/main_screens/tabs/today_tab.dart:12:14

When the exception was thrown, this was the stack:
#0      RenderFlex.performLayout.<anonymous closure> (package:flutter/src/rendering/flex.dart:712:11)
#1      RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:739:10)
#2      RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#3      _RenderSingleChildViewport.performLayout (package:flutter/src/widgets/single_child_scroll_view.dart:544:13)
#4      RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#5      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#6      RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#7      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#8      RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#9      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#10     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#11     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#12     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#13     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#14     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#15     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#16     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#17     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#18     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#19     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#20     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#21     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#22     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#23     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#24     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#25     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#26     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#27     RenderSliverFixedExtentBoxAdaptor.performLayout (package:flutter/src/rendering/sliver_fixed_extent_list.dart:248:18)
#28     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#29     RenderSliverEdgeInsetsPadding.performLayout (package:flutter/src/rendering/sliver_padding.dart:137:11)
#30     _RenderSliverFractionalPadding.performLayout (package:flutter/src/widgets/sliver_fill.dart:170:11)
#31     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#32     RenderViewportBase.layoutChildSequence (package:flutter/src/rendering/viewport.dart:471:13)
#33     RenderViewport._attemptLayout (package:flutter/src/rendering/viewport.dart:1465:12)
#34     RenderViewport.performLayout (package:flutter/src/rendering/viewport.dart:1374:20)
#35     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#36     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#37     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#38     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#39     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#40     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#41     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#42     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#43     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#44     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#45     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#46     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#47     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#48     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#49     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#50     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#51     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#52     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#53     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#54     MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:173:11)
#55     _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:495:7)
#56     MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:242:7)
#57     RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:401:14)
#58     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#59     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#60     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#61     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#62     _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1269:11)
#63     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#64     RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:209:11)
#65     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#66     MultiChildLayoutDelegate.layoutChild (package:flutter/src/rendering/custom_layout.dart:173:11)
#67     _ScaffoldLayout.performLayout (package:flutter/src/material/scaffold.dart:495:7)
#68     MultiChildLayoutDelegate._callPerformLayout (package:flutter/src/rendering/custom_layout.dart:242:7)
#69     RenderCustomMultiChildLayoutBox.performLayout (package:flutter/src/rendering/custom_layout.dart:401:14)
#70     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#71     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#72     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#73     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#74     _RenderCustomClip.performLayout (package:flutter/src/rendering/proxy_box.dart:1269:11)
#75     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#76     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#77     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#78     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#79     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#80     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#81     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#82     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#83     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#84     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#85     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#86     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#87     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#88     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#89     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#90     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#91     RenderOffstage.performLayout (package:flutter/src/rendering/proxy_box.dart:3228:13)
#92     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#93     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#94     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#95     _RenderTheatre.performLayout (package:flutter/src/widgets/overlay.dart:702:15)
#96     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#97     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#98     RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#99     RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#100    RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#101    RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#102    RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#103    RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#104    RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#105    RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:115:13)
#106    RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#107    _RenderLayoutBuilder.performLayout (package:flutter/src/widgets/layout_builder.dart:301:13)
#108    RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#109    _RenderLayoutBuilder.performLayout (package:flutter/src/widgets/layout_builder.dart:301:13)
#110    RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#111    RenderView.performLayout (package:flutter/src/rendering/view.dart:170:13)
#112    RenderObject._layoutWithoutResize (package:flutter/src/rendering/object.dart:1632:7)
#113    PipelineOwner.flushLayout (package:flutter/src/rendering/object.dart:889:18)
#114    RendererBinding.drawFrame (package:flutter/src/rendering/binding.dart:404:19)
#115    WidgetsBinding.drawFrame (package:flutter/src/widgets/binding.dart:867:13)
#116    RendererBinding._handlePersistentFrameCallback (package:flutter/src/rendering/binding.dart:286:5)
#117    SchedulerBinding._invokeFrameCallback (package:flutter/src/scheduler/binding.dart:1117:15)
#118    SchedulerBinding.handleDrawFrame (package:flutter/src/scheduler/binding.dart:1056:9)
#119    SchedulerBinding.scheduleWarmUpFrame.<anonymous closure> (package:flutter/src/scheduler/binding.dart:865:7)
(elided 4 frames from class _RawReceivePortImpl, class _Timer, and dart:async-patch)

The following RenderObject was being processed when the exception was fired: RenderFlex#bf474 relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE:
  creator: Column ← _SingleChildViewport ← IgnorePointer-[GlobalKey#a96e8] ← Semantics ←
    _PointerListener ← Listener ← _GestureSemantics ←
    RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#2d1ee] ← _PointerListener ← Listener
    ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#be83e] ← ⋯
  parentData: <none> (can use size)
  constraints: BoxConstraints(w=360.0, 0.0<=h<=Infinity)
  size: MISSING
  direction: vertical
  mainAxisAlignment: start
  mainAxisSize: max
  crossAxisAlignment: center
  verticalDirection: down
This RenderObject had the following descendants (showing up to depth 5):
    child 1: RenderRepaintBoundary#1afda NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
      child: RenderCustomPaint#35c8e NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
        child: RenderRepaintBoundary#91327 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
          child: _RenderScrollSemantics#85e9b NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
            child: RenderPointerListener#a8cff NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
    child 2: RenderRepaintBoundary#94ff7 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
      child: RenderCustomPaint#064c6 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
        child: RenderRepaintBoundary#032ad NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
          child: _RenderScrollSemantics#2473a NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
            child: RenderPointerListener#8713b NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
════════════════════════════════════════════════════════════════════════════════════════════════════

Another exception was thrown: RenderBox was not laid out: RenderFlex#bf474 relayoutBoundary=up1 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE

Another exception was thrown: RenderBox was not laid out: _RenderSingleChildViewport#7d98f NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE

Another exception was thrown: RenderBox was not laid out: RenderIgnorePointer#17a3e NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE

Another exception was thrown: RenderBox was not laid out: RenderSemanticsAnnotations#434ed NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE

════════ Exception caught by rendering library ═════════════════════════════════════════════════════
The following assertion was thrown during performLayout():
RenderFlex children have non-zero flex but incoming height constraints are unbounded.

When a column is in a parent that does not provide a finite height constraint, for example if it is in a vertical scrollable, it will try to shrink-wrap its children along the vertical axis. Setting a flex on a child (e.g. using Expanded) indicates that the child is to expand to fill the remaining space in the vertical direction.
These two directives are mutually exclusive. If a parent is to shrink-wrap its child, the child cannot simultaneously expand to fit its parent.

Consider setting mainAxisSize to MainAxisSize.min and using FlexFit.loose fits for the flexible children (using Flexible rather than Expanded). This will allow the flexible children to size themselves to less than the infinite remaining space they would otherwise be forced to take, and then will cause the RenderFlex to shrink-wrap the children rather than expanding to fit the maximum constraints provided by the parent.

If this message did not help you determine the problem, consider using debugDumpRenderTree():
  https://flutter.dev/debugging/#rendering-layer
  http://api.flutter.dev/flutter/rendering/debugDumpRenderTree.html
The affected RenderFlex is: RenderFlex#bf474 relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
  parentData: <none> (can use size)
  constraints: BoxConstraints(w=360.0, 0.0<=h<=Infinity)
  size: MISSING
  direction: vertical
  mainAxisAlignment: start
  mainAxisSize: max
  crossAxisAlignment: center
  verticalDirection: down
...  child 1: RenderRepaintBoundary#1afda NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...    needs compositing
...    parentData: offset=Offset(0.0, 0.0); flex=1; fit=FlexFit.tight
...    constraints: MISSING
...    size: MISSING
...    usefulness ratio: no metrics collected yet (never painted)
...    child: RenderCustomPaint#35c8e NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...      parentData: <none>
...      constraints: MISSING
...      size: MISSING
...      child: RenderRepaintBoundary#91327 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...        needs compositing
...        parentData: <none>
...        constraints: MISSING
...        size: MISSING
...        usefulness ratio: no metrics collected yet (never painted)
...        child: _RenderScrollSemantics#85e9b NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...          parentData: <none>
...          constraints: MISSING
...          semantic boundary
...          size: MISSING
...  child 2: RenderRepaintBoundary#94ff7 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...    needs compositing
...    parentData: offset=Offset(0.0, 0.0); flex=1; fit=FlexFit.tight
...    constraints: MISSING
...    size: MISSING
...    usefulness ratio: no metrics collected yet (never painted)
...    child: RenderCustomPaint#064c6 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...      parentData: <none>
...      constraints: MISSING
...      size: MISSING
...      child: RenderRepaintBoundary#032ad NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...        needs compositing
...        parentData: <none>
...        constraints: MISSING
...        size: MISSING
...        usefulness ratio: no metrics collected yet (never painted)
...        child: _RenderScrollSemantics#2473a NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...          parentData: <none>
...          constraints: MISSING
...          semantic boundary
...          size: MISSING
The creator information is set to: Column ← _SingleChildViewport ← IgnorePointer-[GlobalKey#a96e8] ← Semantics ← _PointerListener ← Listener ← _GestureSemantics ← RawGestureDetector-[LabeledGlobalKey<RawGestureDetectorState>#2d1ee] ← _PointerListener ← Listener ← _ScrollableScope ← _ScrollSemantics-[GlobalKey#be83e] ← ⋯
The nearest ancestor providing an unbounded width constraint is: _RenderSingleChildViewport#7d98f NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...  needs compositing
...  parentData: <none> (can use size)
...  constraints: BoxConstraints(w=360.0, h=471.0)
...  size: MISSING

See also: https://flutter.dev/layout/

If none of the above helps enough to fix this problem, please don't hesitate to file a bug:
  https://github.com/flutter/flutter/issues/new?template=BUG.md
The relevant error-causing widget was: 
  Column file:///D:/Other/App/Flutter/flash/lib/main_screens/tabs/today_tab.dart:12:14
When the exception was thrown, this was the stack: 
#0      RenderFlex.performLayout.<anonymous closure> (package:flutter/src/rendering/flex.dart:712:11)
#1      RenderFlex.performLayout (package:flutter/src/rendering/flex.dart:739:10)
#2      RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
#3      _RenderSingleChildViewport.performLayout (package:flutter/src/widgets/single_child_scroll_view.dart:544:13)
#4      RenderObject.layout (package:flutter/src/rendering/object.dart:1769:7)
...
The following RenderObject was being processed when the exception was fired: RenderFlex#bf474 relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...  parentData: <none> (can use size)
...  constraints: BoxConstraints(w=360.0, 0.0<=h<=Infinity)
...  size: MISSING
...  direction: vertical
...  mainAxisAlignment: start
...  mainAxisSize: max
...  crossAxisAlignment: center
...  verticalDirection: down
RenderObject: RenderFlex#bf474 relayoutBoundary=up1 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
  parentData: <none> (can use size)
  constraints: BoxConstraints(w=360.0, 0.0<=h<=Infinity)
  size: MISSING
  direction: vertical
  mainAxisAlignment: start
  mainAxisSize: max
  crossAxisAlignment: center
  verticalDirection: down
...  child 1: RenderRepaintBoundary#1afda NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...    needs compositing
...    parentData: offset=Offset(0.0, 0.0); flex=1; fit=FlexFit.tight
...    constraints: MISSING
...    size: MISSING
...    usefulness ratio: no metrics collected yet (never painted)
...    child: RenderCustomPaint#35c8e NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...      parentData: <none>
...      constraints: MISSING
...      size: MISSING
...      child: RenderRepaintBoundary#91327 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...        needs compositing
...        parentData: <none>
...        constraints: MISSING
...        size: MISSING
...        usefulness ratio: no metrics collected yet (never painted)
...        child: _RenderScrollSemantics#85e9b NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...          parentData: <none>
...          constraints: MISSING
...          semantic boundary
...          size: MISSING
...  child 2: RenderRepaintBoundary#94ff7 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...    needs compositing
...    parentData: offset=Offset(0.0, 0.0); flex=1; fit=FlexFit.tight
...    constraints: MISSING
...    size: MISSING
...    usefulness ratio: no metrics collected yet (never painted)
...    child: RenderCustomPaint#064c6 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...      parentData: <none>
...      constraints: MISSING
...      size: MISSING
...      child: RenderRepaintBoundary#032ad NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...        needs compositing
...        parentData: <none>
...        constraints: MISSING
...        size: MISSING
...        usefulness ratio: no metrics collected yet (never painted)
...        child: _RenderScrollSemantics#2473a NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...          parentData: <none>
...          constraints: MISSING
...          semantic boundary
...          size: MISSING
════════════════════════════════════════════════════════════════════════════════════════════════════

Another exception was thrown: RenderBox was not laid out: RenderPointerListener#dd9af NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE

Another exception was thrown: RenderBox was not laid out: RenderSemanticsGestureHandler#e7712 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE

════════ Exception caught by rendering library ═════════════════════════════════════════════════════
RenderBox was not laid out: RenderFlex#bf474 relayoutBoundary=up1 NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
'package:flutter/src/rendering/box.dart':
Failed assertion: line 1702 pos 12: 'hasSize'
The relevant error-causing widget was: 
  SingleChildScrollView file:///D:/Other/App/Flutter/flash/lib/main_screens/tabs/today_tab.dart:11:12
  

Это мой класс

 class Today extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return SingleChildScrollView(
      child: Column(
        children: [
          Expanded(
            child: ListView1(),
          ),
          Expanded(
            child: ListView2(),
          ),
        ],
      ),
    );
  }
}
  

Это мои ListView1 и ListView2 …. оба класса одинаковы для лучшего понимания.

 class ListView1 extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return ListView.builder(
        itemCount: classData.length,
        shrinkWrap: true,
        physics: NeverScrollableScrollPhysics(),
        itemBuilder: (context, index) {
          return ClassListTile(
            startTime: classData[index].startTime,
            endTime: classData[index].endTime,
            subName: classData[index].subName,
            subCode: classData[index].subCode,
            staffName: classData[index].staffName,
            isPresent: classData[index].isPresent,
          );
        });
  }
}
  

Удалите Expanded виджеты. Они пытаются занять как можно больше места в своем родительском элементе, который в данном случае бесконечен из-за родительского Column элемента, обернутого SingleChildScrollView .

   Widget build(BuildContext context) {
    return SingleChildScrollView(
      child: Column(
        children: [
          ListView1(),
          ListView2(),
        ],
      ),
    );
  }