mapView.bounds being called from background thread.

[arpwal]

UIView.bounds should be called from the main thread.

MKZoomScale MKZoomScaleForMapView(MKMapView *mapView)
{
    MKZoomScale currentZoomScale = mapView.bounds.size.width / mapView.visibleMapRect.size.width;
    
    return currentZoomScale;
}

Stack trace:

PID: 29063, TID: 196647, Thread name: (none), Queue name: com.apple.root.user-initiated-qos, QoS: 25
Backtrace:
4   ABFRealmMapView                     0x000000010432a715 MKZoomScaleForMapView + 85
5   ABFRealmMapView                     0x0000000104332056 -[ABFRealmMapView refreshMapView] + 1766
6   ABFRealmMapView                     0x00000001043345b4 __46-[ABFRealmMapView registerChangeNotification:]_block_invoke_2.232 + 164
7   Realm                               0x0000000106fba0b1 _ZZ23RLMAddNotificationBlockIN5realm7ResultsEEP20RLMNotificationTokenP11objc_objectRT_U13block_pointerFvS5_P19RLMCollectionChangeP7NSErrorEbENKUlRKNS0_19CollectionChangeSetESt13exception_ptrE_clESG_SH_ + 705
8   Realm                               0x0000000106fb9c05 _ZN5realm24CollectionChangeCallback4ImplIZ23RLMAddNotificationBlockINS_7ResultsEEP20RLMNotificationTokenP11objc_objectRT_U13block_pointerFvS7_P19RLMCollectionChangeP7NSErrorEbEUlRKNS_19CollectionChangeSetESt13exception_ptrE_E5afterESI_ + 69
9   Realm                               0x0000000106e7358e _ZN5realm24CollectionChangeCallback5afterERKNS_19CollectionChangeSetE + 46
10  Realm                               0x0000000106e734e9 _ZZN5realm5_impl18CollectionNotifier13after_advanceEvENK3$_9clINSt3__111unique_lockINS4_5mutexEEENS1_8CallbackEEEDaRT_RT0_ + 169
11  Realm                               0x0000000106e5c896 _ZN5realm5_impl18CollectionNotifier17for_each_callbackIZNS1_13after_advanceEvE3$_9EEvOT_ + 166
12  Realm                               0x0000000106e5c7e9 _ZN5realm5_impl18CollectionNotifier13after_advanceEv + 25
13  Realm                               0x0000000106e5dd23 _ZN5realm5_impl15NotifierPackage13after_advanceEv + 147
14  Realm                               0x00000001072611a6 _ZN12_GLOBAL__N_126advance_with_notificationsIZN5realm5_impl11transaction7advanceERKNSt3__110unique_ptrINS1_11SharedGroupENS4_14default_deleteIS6_EEEEPNS1_14BindingContextERNS2_15NotifierPackageEE3$_1EEvSD_SB_OT_SF_ + 998
15  Realm                               0x0000000107260db9 _ZN5realm5_impl11transaction7advanceERKNSt3__110unique_ptrINS_11SharedGroupENS2_14default_deleteIS4_EEEEPNS_14BindingContextERNS0_15NotifierPackageE + 57
16  Realm                               0x0000000106f2274c _ZN5realm5_impl16RealmCoordinator16advance_to_readyERNS_5RealmE + 972
17  Realm                               0x00000001071a28ad _ZN5realm5Realm6notifyEv + 653
18  Realm                               0x00000001072897c0 _ZNK5realm5_impl17WeakRealmNotifier8CallbackclEv + 64
19  Realm                               0x000000010728c92c _ZZN5realm4util15EventLoopSignalINS_5_impl17WeakRealmNotifier8CallbackEEC1EOS4_ENKUlPvE_clES7_ + 28
20  Realm                               0x000000010728c905 _ZZN5realm4util15EventLoopSignalINS_5_impl17WeakRealmNotifier8CallbackEEC1EOS4_ENUlPvE_8__invokeES7_ + 21
21  CoreFoundation                      0x000000010a5ecdb1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
22  CoreFoundation                      0x000000010a5ec633 __CFRunLoopDoSources0 + 243
23  CoreFoundation                      0x000000010a5e6cef __CFRunLoopRun + 1231
24  CoreFoundation                      0x000000010a5e64d2 CFRunLoopRunSpecific + 626
25  CoreFoundation                      0x000000010a5e7458 CFRunLoopRun + 88
26  ABFRealmMapView                     0x0000000104333f51 __46-[ABFRealmMapView registerChangeNotification:]_block_invoke + 193
27  libdispatch.dylib                   0x000000010b3cfd7f _dispatch_call_block_and_release + 12
28  libdispatch.dylib                   0x000000010b3d0db5 _dispatch_client_callout + 8
29  libdispatch.dylib                   0x000000010b3e1806 _dispatch_root_queue_drain + 819
30  libdispatch.dylib                   0x000000010b3e1fca _dispatch_worker_thread2 + 130
31  libsystem_pthread.dylib             0x000000010b7b96b3 _pthread_wqthread + 583
32  libsystem_pthread.dylib             0x000000010b7b93fd start_wqthread + 13