Android Question xSD_OpenMaps & jSD_OpenMaps

stevel05 · 2026-10-31T10:00:18+0000

Using this great library in a B4a and B4j (appropriate versions) cross platform B4xPages app. I am trying to obtain some information on the state of a map view when it is closed, so I can reset it when next opened. I have the sub in a customview that hosts an OpenMaps instance:

Code:

Private Sub btnBack_Click
    wait for (OMaps.getZoom) Complete (Zoom As Int)
    Log("Zoom " & Zoom)
    Wait for (OMaps.XYToLatLng(OMaps.mBase.Width / 2, OMaps.mBase.Height / 2)) Complete (Center As LatLng)
    Log("Center " & Center)
    Wait For(OMaps.CameraPosition) Complete (Pos As CameraPosition)
    Log("CP " & Pos)
 
    Close
    CallSubDelayed2(mCallBack, mEventName & "_Closed", mIndex)
 
End Sub

In B4a getZoom and XYToLatLng both return values, not sure on the validity of XYToLatLng though, so thought I'd use CameraPosition, but in B4a I get the error:

Code:

java.lang.RuntimeException: JSON Object expected.
    at anywheresoftware.b4a.objects.collections.JSONParser.NextObject(JSONParser.java:67)
    at anywheresoftware.b4a.objects.collections.JSONParser$JSONConverter.ToMap(JSONParser.java:289)
    at it.tecnomedia.omap.openmaps$ResumableSub_CameraPosition.resume(openmaps.java:850)
    at anywheresoftware.b4a.BA.checkAndRunWaitForEvent(BA.java:281)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:223)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:209)
    at anywheresoftware.b4a.keywords.Common$15.run(Common.java:1867)
    at android.os.Handler.handleCallback(Handler.java:873)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:193)
    at android.app.ActivityThread.main(ActivityThread.java:6816)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:518)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
java.lang.RuntimeException: JSON Object expected.
    at anywheresoftware.b4a.objects.collections.JSONParser.NextObject(JSONParser.java:67)
    at anywheresoftware.b4a.objects.collections.JSONParser$JSONConverter.ToMap(JSONParser.java:289)
    at it.tecnomedia.omap.openmaps$ResumableSub_CameraPosition.resume(openmaps.java:850)
    at anywheresoftware.b4a.BA.checkAndRunWaitForEvent(BA.java:281)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:223)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:209)
    at anywheresoftware.b4a.keywords.Common$15.run(Common.java:1867)
    at android.os.Handler.handleCallback(Handler.java:873)
    at android.os.Handler.dispatchMessage(Handler.java:99)
    at android.os.Looper.loop(Looper.java:193)
    at android.app.ActivityThread.main(ActivityThread.java:6816)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:518)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

In B4j nothing is ever returned from any of the methods and the app just hangs.

I have tried different program flows including calling the methods in a CallSubDelayed before closing, just in case there were too many resumablesub calls.

Any advice / known issues before I create a test app (could take a while)?

Android Question xSD_OpenMaps & jSD_OpenMaps

stevel05

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