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════════ Exception caught by rendering library ═════════════════════════════════════════════════════
The following assertion was thrown during performLayout():
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.


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=BUG.md

The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
When the exception was thrown, this was the stack: 
#2      RenderObject.layout (package:flutter/src/rendering/object.dart:1651:12)
#3      RenderPadding.performLayout (package:flutter/src/rendering/shifted_box.dart:206:11)
#4      RenderObject.layout (package:flutter/src/rendering/object.dart:1724:7)
#5      RenderProxyBoxMixin.performLayout (package:flutter/src/rendering/proxy_box.dart:105:13)
#6      RenderObject.layout (package:flutter/src/rendering/object.dart:1724:7)
...
The following RenderObject was being processed when the exception was fired: RenderPadding#f8393 relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...  parentData: <none> (can use size)
...  constraints: BoxConstraints(0.0<=w<=376.4, 0.0<=h<=Infinity)
...  size: Size(10.0, 183.0)
...  padding: EdgeInsets(16.0, 0.0, 16.0, 0.0)
...  textDirection: ltr
RenderObject: RenderPadding#f8393 relayoutBoundary=up8 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
  parentData: <none> (can use size)
  constraints: BoxConstraints(0.0<=w<=376.4, 0.0<=h<=Infinity)
  size: Size(10.0, 183.0)
  padding: EdgeInsets(16.0, 0.0, 16.0, 0.0)
  textDirection: ltr
...  child: _RenderListTile#d0a65 relayoutBoundary=up9 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...    parentData: offset=Offset(16.0, 0.0) (can use size)
...    constraints: BoxConstraints(w=0.0, 0.0<=h<=Infinity)
...    size: Size(124.6, 183.0)
...    leading: RenderConstrainedBox#b2443 relayoutBoundary=up10 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...      parentData: offset=Offset(0.0, 16.0) (can use size)
...      constraints: BoxConstraints(w=0.0, 0.0<=h<=56.0)
...      size: Size(0.0, 56.0)
...      additionalConstraints: BoxConstraints(w=80.0, h=80.0)
...      child: RenderDecoratedBox#cde52 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...        parentData: <none> (can use size)
...        constraints: BoxConstraints(w=0.0, h=56.0)
...        size: Size(0.0, 56.0)
...        decoration: BoxDecoration
...          color: Color(0xff1976d2)
...          shape: circle
...        configuration: ImageConfiguration(bundle: PlatformAssetBundle#fc92c(), devicePixelRatio: 3.5, locale: en_US, textDirection: TextDirection.ltr, platform: android)
...        child: RenderPositionedBox#12efe NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...          parentData: <none> (can use size)
...          constraints: BoxConstraints(w=0.0, h=56.0)
...          size: Size(0.0, 56.0)
...          alignment: center
...          textDirection: ltr
...          widthFactor: expand
...          heightFactor: expand
...    title: RenderParagraph#57a5a relayoutBoundary=up10 NEEDS-LAYOUT NEEDS-PAINT NEEDS-COMPOSITING-BITS-UPDATE
...      parentData: offset=Offset(96.0, 4.0) (can use size)
...      constraints: BoxConstraints(w=28.6, 0.0<=h<=Infinity)
...      size: Size(28.6, 175.0)
...      textAlign: start
...      textDirection: ltr
...      softWrap: wrapping at box width
...      overflow: clip
...      locale: en_US
...      maxLines: unlimited
...      text: TextSpan
...        debugLabel: (((englishLike subhead 2014).merge(blackMountainView subhead)).copyWith).merge(unknown)
...        inherit: false
...        color: Color(0xffffffff)
...        family: Roboto
...        size: 30.0
...        weight: 800
...        baseline: alphabetic
...        decoration: TextDecoration.none
...        "Ayman"
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (2) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (3) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (4) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (5) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (6) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (7) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (8) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (9) Exception caught by rendering library ═════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (10) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (11) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (12) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (13) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (14) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (15) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (16) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════

════════ (17) Exception caught by rendering library ════════════════════════════════════════════════
'package:flutter/src/rendering/object.dart': Failed assertion: line 1651 pos 12: '!_debugDoingThisLayout': is not true.
The relevant error-causing widget was: 
  ListTile file:///C:/Users/acer/AndroidStudioProjects/sidebar_animation/lib/sidebar/Sidebar.dart:75:25
════════════════════════════════════════════════════════════════════════════════════════════════════