Question

am using the android support v4- google maps by pete doyle and am trying to delete a mapview and then recreate it again, when i go away from and return to it, but i keep getting the usual Java.lang.IllegalStateException: You are only allowed to have a single MapView in a MapActivity. anyone know ho to solve this correctly. I have this code in my fragment.

Fragment:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    super.onCreateView(inflater, container, savedInstanceState);
    Log.d(TAG, "onCreate View called here in location fragment!!");

    if(view == null){
      view = inflater.inflate(R.layout.map, container, false);  

    frame = (FrameLayout)view.findViewById(R.id.mapContainer);
    //mapview = (MapView)view.findViewById(R.id.mapView);
    }

    if(mapview == null){

        mapview = new MapView(getActivity(), getActivity().getString(R.string.map_api_key));  // keep getting the error on this line
        mapview_is_active = true;
    }

    mapview.setClickable(true);
    mapview.setBuiltInZoomControls(true);
    mapview.setSatellite(true); // Satellite View
    mapview.setStreetView(true); // Street View
    mapview.setTraffic(true); // Traffic View

    frame.addView(mapview,0);



    //frame = (FrameLayout)view.findViewById(R.id.mapContainer);   
   return view;
}


  @Override
    public void onActivityCreated(Bundle savedInstanceState){
        super.onActivityCreated(savedInstanceState);

       if(mapview == null){
           Log.d(TAG, "mapview is null here");
           mapview = new MapView(getActivity(), getActivity().getString(R.string.map_api_key));
       }

       if(frame.getChildAt(0) == null){
           Log.d(TAG, "mapview is null here in container");
           frame.addView(mapview);
       }

        MapController controller = mapview.getController();

        double lat = Double.parseDouble(longitude);
        double lon = Double.parseDouble(latitude);

        GeoPoint geopoint = new GeoPoint((int)(lat * 1E6), (int)(lon * 1E6));

        mapview.invalidate();

        List<Overlay> mapOverlays = mapview.getOverlays();
        Drawable drawable = this.getResources().getDrawable(R.drawable.map_point);
        AddMapOverlay add_map_overlay = new AddMapOverlay(drawable, getActivity());

        OverlayItem overlayitem = new OverlayItem(geopoint, name, address);

        add_map_overlay.addOverlay(overlayitem);

        mapOverlays.add(add_map_overlay);

        controller.animateTo(geopoint);
        controller.setZoom(15);
    }

and in my onStop():

 @Override
    public void onStop(){
        super.onStop(); 

        if(frame != null){
            frame.removeView(mapview); // i remove the mapview here
        }   
    }

here is my map.xml:

<FrameLayout  xmlns:android="http://schemas.android.com/apk/res/android"
   android:id="@+id/mapContainer"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:layout_weight="1">

</FrameLayout>

any help will be greatly appreciated. Thanks

Answer 1

I did this with the below code. I have a MapView instance variable in my FragmentActivity, and then added and removed it in the Fragment itself below (just included the pertinent parts):

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);

    mLayoutMap = (FrameLayout) getActivity().findViewById(R.id.layoutMap);

    // create the map view if it's not already there
    if (((MyActivity)getActivity()).mMapView == null)
    {
        ((MyActivity)getActivity()).mMapView = 
                    new MapView(getActivity(), getActivity().getString(R.string.map_api_key));
        ((MyActivity)getActivity()).mMapView.setClickable(true);
    }

    // add the map view to the frame layout, at the lowest z-index
    mLayoutMap.addView(((MyActivity)getActivity()).mMapView, 0);

}

@Override
 public void onStop()
 {
     super.onStop();

     if (mLayoutMap.getChildCount() > 0 && mLayoutMap.getChildAt(0) instanceof MapView)
         mLayoutMap.removeViewAt(0);
 }

mLayoutMap is just a FrameLayout in my XML.