Android Question GoogleMaps App Crash Mystery

[Andrew (Digitwell)]

I wonder if anyone can help with a problem I am having.

I have an app which is using GoogleMaps within an activity.
In the activity_create I have

  Starter.rp.CheckAndRequest(Starter.rp.PERMISSION_ACCESS_FINE_LOCATION)

    Wait For Activity_PermissionResult (Permission As String, Result As Boolean)
    If Not(Result) Then
        Msgbox("You need to approve Location Permissions to view the map",Starter.gstrApplicationTitle)
        Activity.Finish
    End If

In the Map_ready event I have

        gmap = mfMap.GetMap
    gmap.MyLocationEnabled = True
    gmap.MapType = gmap.MAP_TYPE_NORMAL

However, I am getting crash reports in Crashlytics which say the following:

Fatal Exception: java.lang.SecurityException
my location requires permission ACCESS_FINE_LOCATION or ACCESS_COARSE_LOCATION

com.google.maps.api.android.lib6.impl.bf.c com.google.android.gms.dynamite_mapsdynamite@[email protected] (040408-213742215):551)

com.google.android.gms.maps.internal.l.a com.google.android.gms.dynamite_mapsdynamite@[email protected] (040408-213742215):277)


fq.onTransact com.google.android.gms.dynamite_mapsdynamite@[email protected] (040408-213742215):4)

android.os.Binder.transact (Binder.java:628)

com.google.android.gms.internal.maps.zza.transactAndReadExceptionReturnVoid (Unknown Source:7)

com.google.android.gms.maps.internal.zzg.setMyLocationEnabled (Unknown Source:9)

com.google.android.gms.maps.GoogleMap.setMyLocationEnabled (Unknown Source:2)

anywheresoftware.b4a.objects.MapFragmentWrapper$GoogleMapWrapper.setMyLocationEnabled (MapFragmentWrapper.java:307)

uk.co.digitwell.interdirect.mkccm.parkmycar._mfmap_ready (parkmycar.java:1377)

The crash seems to suggest that the user did not approve the ACCESS_FINE_LOCATION permission, which is odd because the Activity_Create should exit.

Does anyone have any ideas why this is happening?

Thanks

 

[DonManfred]

DO NOT set the property in the designer (EnableMyLocation or so).
Wait for the answer in the RP-Call and set it later in Map_ready event. But only if you HAVE permission....

 

[Andrew (Digitwell)]

Manfred that is exactly what I am doing.

In the designer, the My Location Enabled is not set.

It doesn't happen to everyone who runs the app, just on the very odd occasion.

 

[Andrew (Digitwell)]

Ah, I think I have it! @DonManfred your comment gave me a clue.

In the Activity_create I have already loaded the layout, with the Map Fragment BEFORE calling CheckAndRequest.

If the User, takes a long time to decide to allow or refuse the permission, the Map_ready event is fired, whilst waiting for the PermissionResult.

Now when the code calls
gmap.MyLocationEnabled = True

in the map ready event, the permission has not been approved.

Solution:
I think I need to move the permission check to before the LoadLayout and all will be fine.

What do you think?

 

[DonManfred]

Now when the code calls
gmap.MyLocationEnabled = True

in the map ready event, the permission has not been approved.

Only set this property IF you HAVE permission. Use a global flag to remember. If you do not have permission; do not change the property.

 

[Andrew (Digitwell)]

Yes, I will include that as well, but I think the problem was events firing out of the expected order.

Expected:

Activity Create
Application_PermissionResult
Map_ready​

Actual:

Actvity_create
Map_ready <-- this event arrives before expected because the user does not click on the permission dialog for a long time.
Application_permissionResult - Too late now!
​

If the user refuses the permission I close the activity.

 

[Erel]

Proper way to handle this permission: https://www.b4x.com/android/forum/t...ty-exemptions-on-android-7.88995/#post-563422

 

[Andrew (Digitwell)]

Great thanks for that. Will update my code.