Android Question googlemaps v2, get my length and latitude

mvera

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Longtime User
Hi. work with googlemaps v2 and I was surprised how quickly I locate my location,
how can I get the value of latitude and longitude?

Thank you
 

Alexander Stolte

Expert
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Longtime User
Hey,

quick and 1 Minute of search in the docu.:

B4X:
Sub Globals
Private gmap As GoogleMap
Private MapFragment1 As MapFragment
End Sub

Sub MapFragment1_Ready
gmap = MapFragment1.GetMap
Dim lat as float
Dim lon as float
lat = gmap.MyLocation.latitude
lon = gmap.MyLocation.longitude
End Sub
 
Last edited:
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Alexander Stolte

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Longtime User
If you dont need the map, just the lat and lon, then set the mapfragment visible = false. The Google Maps API is very fast on track the current pos., the GPS lib. is quite slow in my opinion.
 
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mvera

Active Member
Licensed User
Longtime User
thank you all, I am trying to apply what Alexander Stolte says, but it shows the following error:


Error occurred on line: 69 (principal)
java.lang.RuntimeException: Object should first be initialized (LatLng).

B4X:
Sub Globals   
    private gmap As GoogleMap
    Private MapFragment1 As MapFragment
End Sub

Sub Activity_Create(FirstTime As Boolean)
    'Do not forget to load the layout file created with the visual designer. For example:
    Activity.LoadLayout("principal")
   
   
    If MapFragment1.IsGooglePlayServicesAvailable = False Then
        ToastMessageShow("Please install Google Play Services.", True)
    End If
   
   
   
End Sub

Sub MapFragment1_Ready

    Log("LLEGO A MFRAGMENT")
   
   
    gmap =MapFragment1.GetMap
    Dim lat As Float
    Dim lon As Float
    (line 69)  lat = gmap.MyLocation.Latitude
    lon = gmap.MyLocation.longitude
   
    Log("LATITUD "&lat)
   
   
End Sub


I'm not clear how to solve it.
thanks again
 
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mvera

Active Member
Licensed User
Longtime User
but first it shows this error


error occurred on line: 69 (principal)
java.lang.RuntimeException: Object should first be initialized (GoogleMap).
at anywheresoftware.b4a.AbsObjectWrapper.getObject(AbsObjectWrapper.java:50)
at anywheresoftware.b4a.objects.MapFragmentWrapper$GoogleMapWrapper.getMyLocation(MapFragmentWrapper.java:321)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:710)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:339)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:249)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:139)
at anywheresoftware.b4a.BA$1.run(BA.java:325)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:158)
at android.app.ActivityThread.main(ActivityThread.java:7224)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
 
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mvera

Active Member
Licensed User
Longtime User
manage the first error
but another continues.

Error occurred on line: 73 (principal)
java.lang.RuntimeException: Object should first be initialized (LatLng).


B4X:
Sub MapFragment1_Ready
   
   
    gmap =MapFragment1.GetMap
    Dim lat,lon As String
   
    If gmap.IsInitialized = False Then
        ToastMessageShow("Error initializing map.", True)
    Else
       
     (line 73)   lat = gmap.MyLocation.Latitude
        lon = gmap.MyLocation.longitude
       
       
        gmap.AddMarker(36, 15, "Hello!!!")
        Dim cp As CameraPosition
        cp.Initialize(36, 15, gmap.CameraPosition.Zoom)
        gmap.AnimateCamera(cp)
    End If
 
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Alexander Stolte

Expert
Licensed User
Longtime User
Try this:

B4X:
Sub Globals 
    private gmap As GoogleMap
    Private MapFragment1 As MapFragment
End Sub

Sub Activity_Create(FirstTime As Boolean)
    'Do not forget to load the layout file created with the visual designer. For example:
    Activity.LoadLayout("frm_main")
 
  If MapFragment1.IsGooglePlayServicesAvailable = False Then
        ToastMessageShow("Please install Google Play Services.", True)
    End If
 
 
Dim lat as float
Dim lon as float

Wait For MapFragment1_Ready  'it waits until MapFragment1 is ready
            gmap = MapFragment1.GetMap
            If gmap.IsInitialized Then
                Do While Not(gmap.MyLocation.IsInitialized)
                    Sleep(0)
                Loop
              
                lat = gmap.MyLocation.Latitude
                lon = gmap.MyLocation.Longitude
 
End Sub

Sub MapFragment1_Ready

End Sub

My experience has shown that it does not matter whether one is in it or not, if one has internet in it finds coordinates, if he finds GPS then it refers it from there .
 
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