[BUG] example runs into error on connected iPad

[HeikoMueller]

Your Environment

• Plugin version:
  0.6.0

• Platform: iOS or Android
  iOS

• OS version:
  13.6.1

• Device manufacturer / model:
  iPad Air2

• Flutter info (flutter info, flutter doctor):
  Doctor summary (to see all details, run flutter doctor -v):
  [✓] Flutter (Channel stable, 1.20.2, on Mac OS X 10.15.7 19H2, locale de-DE)
  [✓] Android toolchain - develop for Android devices (Android SDK version 29.0.2)
  [✓] Xcode - develop for iOS and macOS (Xcode 11.6)
  [✓] Android Studio (version 3.6)
  [✓] VS Code (version 1.50.1)
  [✓] Connected device (1 available)
  • No issues found!

• Plugin config
  minimumFetchInterval: 15,
  stopOnTerminate: false,
  enableHeadless: false,
  requiresBatteryNotLow: false,
  requiresCharging: false,
  requiresStorageNotLow: false,
  requiresDeviceIdle: false,
  requiredNetworkType: NetworkType.NONE

To Reproduce
Steps to reproduce the behavior:

1. run the example on https://pub.dev/packages/background_fetch on a connected iPad
2. turn the switcher off
3. turn the switcher on again
4. see the bug

Debug logs
2020-11-02 12:57:09.768435+0100 Runner[525:110491] [TSBackgroundFetch load]: (
)
2020-11-02 12:57:09.769051+0100 Runner[525:110491] [TSBGAppRefreshSubscriber load]: {
"flutter_background_fetch" = "";
}
2020-11-02 12:57:10.064981+0100 Runner[525:110491] Metal API Validation Enabled
2020-11-02 12:57:10.270527+0100 Runner[525:110491] Starting Up...
2020-11-02 12:57:10.298799+0100 Runner[525:110491] [[CENTRAL]] add callbackChannel
2020-11-02 12:57:10.347779+0100 Runner[525:110673] [[CENTRAL]] CENTRAL STATE IS NOT POWERED ON
2020-11-02 12:57:10.350982+0100 Runner[525:110673] [[CENTRAL]] CBManager Central is powered on
2020-11-02 12:57:10.542517+0100 Runner[525:110687] flutter: Observatory listening on http://127.0.0.1:53622/MykNonjcE7o=/
[PERIPHERAL] CBManager is powered on
2020-11-02 12:57:11.263220+0100 Runner[525:110491] [TSBackgroundFetch scheduleBGAppRefresh] com.transistorsoft.fetch
2020-11-02 12:57:12.690611+0100 Runner[525:110679] flutter: [BackgroundFetch] configure success: 2
2020-11-02 12:57:17.314799+0100 Runner[525:110682] [VERBOSE-2:profiler_metrics_ios.mm(184)] Error retrieving thread information: (os/kern) invalid argument
2020-11-02 12:57:35.288276+0100 Runner[525:110491] [TSBackgroundFetch stop] (null)
2020-11-02 12:57:35.313274+0100 Runner[525:110679] flutter: [BackgroundFetch] stop success: 2
2020-11-02 12:57:38.043431+0100 Runner[525:110491] [TSBackgroundFetch start] (null)
2020-11-02 12:57:38.043608+0100 Runner[525:110491] [TSBackgroundFetch scheduleBGAppRefresh] com.transistorsoft.fetch
2020-11-02 12:57:38.086035+0100 Runner[525:110679] [VERBOSE-2:ui_dart_state.cc(166)] Unhandled Exception: Invalid argument(s) (error): Must not be null
#0 ArgumentError.checkNotNull (dart:core/errors.dart:194:27)
#1 _Completer.completeError (dart:async/future_impl.dart:21:19)
#2 BackgroundFetch.start. (package:background_fetch/background_fetch.dart:402:17)
#3 _rootRunUnary (dart:async/zone.dart:1198:47)
#4 _CustomZone.runUnary (dart:async/zone.dart:1100:19)
#5 _FutureListener.handleError (dart:async/future_impl.dart:160:20)
#6 Future._propagateToListeners.handleError (dart:async/future_impl.dart:708:47)
#7 Future._propagateToListeners (dart:async/future_impl.dart:729:24)
#8 Future._completeError (dart:async/future_impl.dart:537:5)
#9 _AsyncAwaitCompleter.completeError (dart:async-patch/async_patch.dart:47:15)
#10 MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart)

#11 MethodChannel.invokeMethod (package:flutter/src/services/platform_channel.dart:334:12)
#12 BackgroundFetch.start (package:background_fetch/background_fetch.dart:399:20)
#13 _MyAppState._onClickEnable (package:wegotracy/main.dart:89:23)
#14 RenderToggleable._handleTap (package:flutter/src/material/toggleable.dart:413:18)
#15 GestureRecognizer.invokeCallback (package:flutter/src/gestures/recognizer.dart:184:24)
#16 TapGestureRecognizer.handleTapUp (package:flutter/src/gestures/tap.dart:524:11)
#17 BaseTapGestureRecognizer._checkUp (package:flutter/src/gestures/tap.dart:284:5)
#18 BaseTapGestureRecognizer.acceptGesture (package:flutter/src/gestures/tap.dart:256:7)
#19 GestureArenaManager.sweep (package:flutter/src/gestures/arena.dart:158:27)
#20 GestureBinding.handleEvent (package:flutter/src/gestures/binding.dart:224:20)
#21 GestureBinding.dispatchEvent (package:flutter/src/gestures/binding.dart:200:22)
#22 GestureBinding._handlePointerEvent (package:flutter/src/gestures/binding.dart:158:7)
#23 GestureBinding._flushPointerEventQueue (package:flutter/src/gestures/binding.dart:104:7)
#24 GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:88:7)
#25 _rootRunUnary (dart:async/zone.dart:1206:13)
#26 _CustomZone.runUnary (dart:async/zone.dart:1100:19)
#27 _CustomZone.runUnaryGuarded (dart:async/zone.dart:1005:7)
#28 _invoke1 (dart:ui/hooks.dart:267:10)
#29 _dispatchPointerDataPacket (dart:ui/hooks.dart:176:5)

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions. You may also mark this issue as a "discussion" and I will leave this open.

[stale]

Closing this issue after a prolonged period of inactivity. Fell free to reopen this issue, if this still affecting you.