example app crashes

[garyloud]

I'm sure I'm doing something wrong but the example app crashes.
This is using Android Studio targeting iOS using the simulator. I also got the same results when targeting my iPhone.
XXXXX below is really ("latitude"). When I included it along with the [] the preview blanked it out.
I'm just starting with Flutter so I'm sure this is an error on my part but a google search has turned up nothing. The following was copied from the console.

Launching lib/main.dart on iPad Air in debug mode...
Running Xcode clean...
Starting Xcode build...
Xcode build done
Syncing files to device iPad Air...
══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
The following NoSuchMethodError was thrown building MyApp(dirty, state: _MyAppState#5aec3):
The method '[]' was called on null.
Receiver: null
Tried calling:[]XXXXX

When the exception was thrown, this was the stack:
#0 Object.noSuchMethod (dart:core-patch/dart:core/object_patch.dart:46)
#1 _MyAppState.build (/Users/garyloudermilk/AndroidStudioProjects/flutter_app/lib/main.dart:64:107)
#2 StatefulElement.build (package:flutter/src/widgets/framework.dart:3713:27)
#3 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3625:15)
#4 Element.rebuild (package:flutter/src/widgets/framework.dart:3478:5)
#5 ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3605:5)
#6 StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3741:22)
#7 ComponentElement.mount (package:flutter/src/widgets/framework.dart:3600:5)
#8 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2890:14)
#9 Element.updateChild (package:flutter/src/widgets/framework.dart:2693:12)
#10 RenderObjectToWidgetElement._rebuild (package:flutter/src/widgets/binding.dart:852:16)
#11 RenderObjectToWidgetElement.mount (package:flutter/src/widgets/binding.dart:823:5)
#12 RenderObjectToWidgetAdapter.attachToRenderTree. (package:flutter/src/widgets/binding.dart:769:17)
#13 BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2205:19)
#14 RenderObjectToWidgetAdapter.attachToRenderTree (package:flutter/src/widgets/binding.dart:768:13)
#15 BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding&WidgetsBinding.attachRootWidget (package:flutter/src/widgets/binding.dart:657:7)
#16 runApp (package:flutter/src/widgets/binding.dart:699:7)
#17 main (/Users/garyloudermilk/AndroidStudioProjects/flutter_app/lib/main.dart:7:3)
#18 _startIsolate. (dart:isolate-patch/dart:isolate/isolate_patch.dart:279)
#19 _RawReceivePortImpl._handleMessage (dart:isolate-patch/dart:isolate/isolate_patch.dart:165)
════════════════════════════════════════════════════════════════════════════════════════════════════
*** First throw call stack:
(
0 CoreFoundation 0x0000000106a3712b __exceptionPreprocess + 171
1 libobjc.A.dylib 0x00000001060cbf41 objc_exception_throw + 48
2 CoreFoundation 0x0000000106aac245 +[NSException raise:format:] + 197
3 Runner 0x00000001042ce5e5 -[LocationPlugin handleMethodCall:result:] + 789
4 Flutter 0x00000001043a2785 __45-[FlutterMethodChannel setMethodCallHandler:]_block_invoke + 118
5 Flutter 0x00000001043b8d53 _ZN5shell15PlatformViewIOS21HandlePlatformMessageEN3fxl6RefPtrIN5blink15PlatformMessageEEE + 189
6 Flutter 0x00000001043e12af _ZNSt3__110<…>
Lost connection to device.

[clemens-tolboom]

I just checked out this repo then

cd examples
flutter packages get
flutter run

and got the same stacktrace which is caused by location permissions not given yet. I got the Allow location permissions dialog in the app on the simulator. Next I saw lon/lat data.

• After Hardware restart starting the app it crashed.
• Checking the permissions for the app these were set OK. Restarting the App I got lon/lat again.

I guess this is a timing problem somehow?

[Tom1827]

Same for me as @garyloud. Followed the install instructions, copy/paste the exact example code, and:

`══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
The following NoSuchMethodError was thrown building MyApp(dirty, state: _MyAppState#01986):
The method '[]' was called on null.
Receiver: null
Tried calling:

When the exception was thrown, this was the stack:
#0 Object.noSuchMethod (dart:core-patch/dart:core/object_patch.dart:46)
#1 _MyAppState.build (/Users/tom/Google Drive/prog/flutter/gps_test/lib/main.dart:64:107)
#2 StatefulElement.build (package:flutter/src/widgets/framework.dart:3690:27)
#3 ComponentElement.performRebuild (package:flutter/src/widgets/framework.dart:3602:15)
#4 Element.rebuild (package:flutter/src/widgets/framework.dart:3463:5)
#5 ComponentElement._firstBuild (package:flutter/src/widgets/framework.dart:3582:5)
#6 StatefulElement._firstBuild (package:flutter/src/widgets/framework.dart:3718:22)
#7 ComponentElement.mount (package:flutter/src/widgets/framework.dart:3577:5)
#8 Element.inflateWidget (package:flutter/src/widgets/framework.dart:2875:14)
#9 Element.updateChild (package:flutter/src/widgets/framework.dart:2678:12)
#10 RenderObjectToWidgetElement._rebuild (package:flutter/src/widgets/binding.dart:852:16)
#11 RenderObjectToWidgetElement.mount (package:flutter/src/widgets/binding.dart:823:5)
#12 RenderObjectToWidgetAdapter.attachToRenderTree. (package:flutter/src/widgets/binding.dart:769:17)
#13 BuildOwner.buildScope (package:flutter/src/widgets/framework.dart:2190:19)
#14 RenderObjectToWidgetAdapter.attachToRenderTree (package:flutter/src/widgets/binding.dart:768:13)
#15 BindingBase&GestureBinding&ServicesBinding&SchedulerBinding&PaintingBinding&RendererBinding&WidgetsBinding.attachRootWidget (package:flutter/src/widgets/binding.dart:657:7)
#16 runApp (package:flutter/src/widgets/binding.dart:699:7)
#17 main (/Users/tom/Google Drive/prog/flutter/gps_test/lib/main.dart:7:3)
#18 _startIsolate. (dart:isolate-patch/dart:isolate/isolate_patch.dart:278)
#19 _RawReceivePortImpl._handleMessage (dart:isolate-patch/dart:isolate/isolate_patch.dart:164)
════════════════════════════════════════════════════════════════════════════════════════════════════
*** First throw call stack:
(
0 CoreFoundation 0x00000001096ca12b __exceptionPreprocess + 171
1 libobjc.A.dylib 0x0000000108d5ef41 objc_exception_throw + 48
2 CoreFoundation 0x000000010973f245 +[NSException raise:format:] + 197
3 Runner 0x0000000106f385e5 -[LocationPlugin handleMethodCall:result:] + 789
4 Flutter 0x000000010700b880 __45-[FlutterMethodChannel setMethodCallHandler:]_block_invoke + 118
5 Flutter 0x0000000107020583 _ZN5shell15PlatformViewIOS21HandlePlatformMessageEN3fxl6RefPtrIN5blink15PlatformMessageEEE + 189
6 Flutter 0x0000000107048e93 _ZNSt3__110<…>`

[clemens-tolboom]

@Tom1827 why paste the same info again into the issue? Please try to add new info :-)

[Lyokone]

This should be fixed with the new version, feel free to open again if it's not.