Region Create Error

[n13]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior:

1. Create a region

Current behavior
Crash

Expected behavior
No crash

Analysis

These two getters are incorrect.

  Stream<List<RegionMessageModel>> get regionMessages => _firebaseRepository.getMessagesForRegion(state.region!.id);

  Stream<List<RegionEventModel>> get regionEvents => _firebaseRepository.getEventsForRegion(state.region!.id);

state.region can be null - so this crashes when region is null.

I don't know why region is null here, but the way to fix it is

• Either make the state.region never be null (not nullable)
  Or
• Deal with it being null here

I was not sure which is better in this case, since it seems that what needs to happen is that this view shows at some point with the region being == null, then later updates with the region != null.

I did not look into why region was null there, but the fundamental problem is forcing the nullable - this is a logical error in the code. Either it can't be null - or it can be and needs to be dealt with.

@RaulUrtecho to investigate.

Screenshots

Platform & App Version

• iOS

Additional context

flutter: Transition { currentState: TransactionsListState(null, PageState.failure, [TransactionModel(a354a8f353c82bcfe6eb87de3c2f27bbfdb7b5e89bffbaf7182f4f27959a68d5), TransactionModel(6e9b98425790257729162ca49fed3c3f1f58deb6e897dabd2fa94eafac791a91), TransactionModel(f7ed44123f8db24075879caf7a481776faf2cff0db9552e522f4726632da6b53), TransactionModel(f7ed44123f8db24075879caf7a481776faf2cff0db9552e522f4726632da6b53), TransactionModel(50b21b8058cb99b346a7426921cb38873665adf606dd329e374dfab7aca4c535), TransactionModel(40e2c9cee66340ed9bb1d3d6d58338e480802746c91ee539e865e81fcc0ecd11), TransactionModel(40e2c9cee66340ed9bb1d3d6d58338e480802746c91ee539e865e81fcc0ecd11), TransactionModel(53ac57dce601ba869d31bafcfe37acb7e104fb22550013a1d81da895a1d0c497), TransactionModel(53ac57dce601ba869d31bafcfe37acb7e104fb22550013a1d81da895a1d0c497), TransactionModel(56a76443b69ff704c9c06a33bd22658bc21a432c814e6971aeacaee30370f0d8), TransactionModel(a7be3ad974a0e91a14487f8512aa8c8765e68b171ea7d80b120e95f2ff887a85), T<…>
flutter: mapEosResponse - transaction id: 746210ba962428195101526eb05f3e9f63bc3791b8f4096f610b270d64be58a2
flutter: Model Class: Closure: (dynamic) => TransactionResponse
flutter: Transaction ID: 746210ba962428195101526eb05f3e9f63bc3791b8f4096f610b270d64be58a2
flutter: Transition { currentState: CreateRegionState(PageState.loading, null, CreateRegionScreen.reviewRegion, The Metaverse, The Metaverse. A virtual Region. , File: '/Users/elohim/Library/Developer/CoreSimulator/Devices/482A42C3-DF3A-47B3-B0B9-C3A096D396EF/data/Containers/Data/Application/B98F95FD-9BC7-4DEB-8AED-C7294994ED29/tmp/image_cropper_432C1643-3C6D-46F5-B372-5EDC70D44299-87501-00013DCA905C4AE7.jpg', https://firebasestorage.googleapis.com/v0/b/seeds-77371.appspot.com/o/regionImage%2Fthemetav%2Fa941ad9f-aa98-4e14-9cbb-7c0023f2a29a%20%20.jpg?alt=media&token=f82cecb2-fd42-4ded-8168-e64e35efef8b, PictureBoxState.imagePicked, themetav, null, Instance of 'Place', RegionIdStatusIcon.valid, false, false), event: onCreateRegionTapped, nextState: CreateRegionState(PageState.success, Instance of 'NavigateToRoute', CreateRegionScreen.reviewRegion, The Metaverse, The Metaverse. A virtual Region. , File: '/Users/elohim/Library/Developer/CoreSimulator/Devices/482A42C3-DF3A-47B3-B0B9-C3A096D396EF/dat<…>

flutter: Transition { currentState: CreateRegionState(PageState.success, Instance of 'NavigateToRoute', CreateRegionScreen.reviewRegion, The Metaverse, The Metaverse. A virtual Region. , File: '/Users/elohim/Library/Developer/CoreSimulator/Devices/482A42C3-DF3A-47B3-B0B9-C3A096D396EF/data/Containers/Data/Application/B98F95FD-9BC7-4DEB-8AED-C7294994ED29/tmp/image_cropper_432C1643-3C6D-46F5-B372-5EDC70D44299-87501-00013DCA905C4AE7.jpg', https://firebasestorage.googleapis.com/v0/b/seeds-77371.appspot.com/o/regionImage%2Fthemetav%2Fa941ad9f-aa98-4e14-9cbb-7c0023f2a29a%20%20.jpg?alt=media&token=f82cecb2-fd42-4ded-8168-e64e35efef8b, PictureBoxState.imagePicked, themetav, null, Instance of 'Place', RegionIdStatusIcon.valid, false, false), event: clearCreateRegionPageCommand , nextState: CreateRegionState(PageState.success, null, CreateRegionScreen.reviewRegion, The Metaverse, The Metaverse. A virtual Region. , File: '/Users/elohim/Library/Developer/CoreSimulator/Devices/482A42C3-DF3A-47B3-B0B9-C3A096D<…>
flutter: OnRegionMounted

The following _CastError was thrown building BlocBuilder<RegionBloc, RegionState>(dirty, dependencies: [_InheritedProviderScope<RegionBloc?>], state: _BlocBuilderBaseState<RegionBloc, RegionState>#9d893):
Null check operator used on a null value

The relevant error-causing widget was
BlocBuilder<RegionBloc, RegionState>
package:seeds/…/components/region_events.dart:14
When the exception was thrown, this was the stack
#0 RegionBloc.regionEvents
package:seeds/…/viewmodel/region_bloc.dart:53
#1 RegionEvents.build.
package:seeds/…/components/region_events.dart:26
#2 BlocBuilder.build
package:flutter_bloc/src/bloc_builder.dart:90
#3 _BlocBuilderBaseState.build
package:flutter_bloc/src/bloc_builder.dart:166
#4 StatefulElement.build
package:flutter/…/widgets/framework.dart:4919
#5 ComponentElement.performRebuild
package:flutter/…/widgets/framework.dart:4806
#6 StatefulElement.performRebuild
package:flutter/…/widgets/framework.dart:4977
#7 Element.rebuild
package:flutter/…/widgets/framework.dart:4529
#8 ComponentElement._firstBuild
package:flutter/…/widgets/framework.dart:4787
#9 StatefulElement._firstBuild
package:flutter/…/widgets/framework.dart:4968
#10 ComponentElement.mount
package:flutter/…/widgets/framework.dart:4781
... Normal element mounting (45 frames)

Add any other context about the problem here.
#128 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#129 RenderProxyBoxMixin.performLayout
package:flutter/…/rendering/proxy_box.dart:116
#130 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#131 RenderProxyBoxMixin.performLayout
package:flutter/…/rendering/proxy_box.dart:116
#132 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#133 RenderProxyBoxMixin.performLayout
package:flutter/…/rendering/proxy_box.dart:116
#134 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#135 RenderProxyBoxMixin.performLayout
package:flutter/…/rendering/proxy_box.dart:116
#136 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#137 RenderProxyBoxMixin.performLayout
package:flutter/…/rendering/proxy_box.dart:116
#138 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#139 RenderOffstage.performLayout
package:flutter/…/rendering/proxy_box.dart:3460
#140 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#141 RenderProxyBoxMixin.performLayout
package:flutter/…/rendering/proxy_box.dart:116
#142 RenderObject.layout
package:flutter/…/rendering/object.dart:1915
#143 _RenderTheatre.performLayout
package:flutter/…/widgets/overlay.dart:749
#144 RenderObject._layoutWithoutResize
package:flutter/…/rendering/object.dart:1757
#145 PipelineOwner.flushLayout
package:flutter/…/rendering/object.dart:887
#146 RendererBinding.drawFrame
package:flutter/…/rendering/binding.dart:504
#147 WidgetsBinding.drawFrame
package:flutter/…/widgets/binding.dart:892
#148 SchedulerBinding._invokeFrameCallback
package:flutter/…/scheduler/binding.dart:1146
#149 SchedulerBinding.handleDrawFrame
package:flutter/…/scheduler/binding.dart:1083
#153 _invoke (dart:ui/hooks.dart:151:10)
#154 PlatformDispatcher._drawFrame (dart:ui/platform_dispatcher.dart:308:5)
#155 _drawFrame (dart:ui/hooks.dart:115:31)
(elided 3 frames from dart:async)
════════════════════════════════════════════════════════════════════════════════

flutter: Transition { currentState: TransactionsListState(null, PageState.failure, [TransactionModel(a354a8f353c82bcfe6eb87de3c2f27bbfdb7b5e89bffbaf7182f4f27959a68d5), TransactionModel(6e9b98425790257729162ca49fed3c3f1f58deb6e897dabd2fa94eafac791a91), TransactionModel(f7ed44123f8db24075879caf7a481776faf2cff0db9552e522f4726632da6b53), TransactionModel(f7ed44123f8db24075879caf7a481776faf2cff0db9552e522f4726632da6b53), TransactionModel(50b21b8058cb99b346a7426921cb38873665adf606dd329e374dfab7aca4c535), TransactionModel(40e2c9cee66340ed9bb1d3d6d58338e480802746c91ee539e865e81fcc0ecd11), TransactionModel(40e2c9cee66340ed9bb1d3d6d58338e480802746c91ee539e865e81fcc0ecd11), TransactionModel(53ac57dce601ba869d31bafcfe37acb7e104fb22550013a1d81da895a1d0c497), TransactionModel(53ac57dce601ba869d31bafcfe37acb7e104fb22550013a1d81da895a1d0c497), TransactionModel(56a76443b69ff704c9c06a33bd22658bc21a432c814e6971aeacaee30370f0d8), TransactionModel(a7be3ad974a0e91a14487f8512aa8c8765e68b171ea7d80b120e95f2ff887a85), T<…>
flutter: OnTick
flutter: Transition { currentState: TransactionsListState(null, PageState.failure, [TransactionModel(a354a8f353c82bcfe6eb87de3c2f27bbfdb7b5e89bffbaf7182f4f27959a68d5), TransactionModel(6e9b98425790257729162ca49fed3c3f1f58deb6e897dabd2fa94eafac791a91), TransactionModel(f7ed44123f8db24075879caf7a481776faf2cff0db9552e522f4726632da6b53), TransactionModel(f7ed44123f8db24075879caf7a481776faf2cff0db9552e522f4726632da6b53), TransactionModel(50b21b8058cb99b346a7426921cb38873665adf606dd329e374dfab7aca4c535), TransactionModel(40e2c9cee66340ed9bb1d3d6d58338e480802746c91ee539e865e81fcc0ecd11), TransactionModel(40e2c9cee66340ed9bb1d3d6d58338e480802746c91ee539e865e81fcc0ecd11), TransactionModel(53ac57dce601ba869d31bafcfe37acb7e104fb22550013a1d81da895a1d0c497), TransactionModel(53ac57dce601ba869d31bafcfe37acb7e104fb22550013a1d81da895a1d0c497), TransactionModel(56a76443b69ff704c9c06a33bd22658bc21a432c814e6971aeacaee30370f0d8), TransactionModel(a7be3ad974a0e91a14487f8512aa8c8765e68b171ea7d80b120e95f2ff887a85), T<…>