Question

So I’m just trying to create a generic mapView in android and put a few geopoints in it. I’ve followed the instructions from the android developer website and had no success… can anyone help? here is my code.

public class HelloItemizedOverlay extends ItemizedOverlay {

    private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
    Context mContext;

    public HelloItemizedOverlay(Drawable defaultMarker, Context context) {
        // defines the bounds for the overlayItems
        super(boundCenterBottom(defaultMarker));
        mContext = context;
    }

    @Override
    protected OverlayItem createItem(int i) {
        // returns the correct ArrayList position from int i
        return mOverlays.get(i);
    }

    @Override
    public int size() {
        // returns number of items in ArrayList
        return mOverlays.size();
    }

    public void addOverlay(OverlayItem overlay) {
        mOverlays.add(overlay);
        populate();
    }

    @Override
    protected boolean onTap(int index) {
        OverlayItem item = mOverlays.get(index);
        AlertDialog.Builder dialog = new AlertDialog.Builder(mContext);
        dialog.setTitle(item.getTitle());
        dialog.setMessage(item.getSnippet());
        dialog.show();
        return true;
    }

}

//Here’s my main class

@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.maptastic);
        ((TextView)((FrameLayout)((LinearLayout)((ViewGroup) getWindow().getDecorView()).getChildAt(0)).getChildAt(0)).getChildAt(0)).setGravity(Gravity.CENTER);
        setTitle("Field Trip");

        Drawable drawable = this.getResources().getDrawable(R.drawable.supaaaa);
        HelloItemizedOverlay itemizedoverlay = new HelloItemizedOverlay(drawable,this);
        //initControls();

        MapView mapview = (MapView) findViewById(R.id.mapView);

        mapview.setBuiltInZoomControls(true);

        mcontroller = mapview.getController();
        // Plot all geo points
        for (Entry<Integer, FieldTripStop> cur : Statics.fieldTripStops.entrySet())
        {
            // get the FieldTripStop object from the current hash table entry
            Statics.currentFTStop = cur.getValue();
            // concatenate numbers before (all) and after (6) the decimal, since
            // geopoints only accept 6 numbers past the decimal.
            theLat = Statics.currentFTStop.latitude;
            theLong = Statics.currentFTStop.longitude;

            /*
             * String manipulation method
             * 
             * theLat = theLat.replace(".","");
             * theLat = theLat.substring(0, 8);
             * theLong = theLong.replace(".","");
             * theLong = theLong.substring(0, 8);
             * point = new GeoPoint((int)(Integer.valueOf(theLat)), (int)(Integer.valueOf(theLong))); 
             */

            theDLat = Double.parseDouble(theLat);
            theDLong = Double.parseDouble(theLong);



            //olay = new OverlayItem(point, "herp", "derp");
            //olayitems.add(olay);
            List<Overlay> mapOverlays = mapview.getOverlays();





            point = new GeoPoint((int)(theDLat*1E6), (int)(theDLong*1E6));
            OverlayItem overlayitem = new OverlayItem(point, "holda, Mundo!", "I'm in Mexico City~!");

            itemizedoverlay.addOverlay(overlayitem);
            mapOverlays.add(itemizedoverlay);

        }

Answer 1

You need to a) use only a single HelloItemizedOverlay (instead one for each point) and b) add this overlay to the map before you add the markers (In your current code, the overlay is not yet associated with the map when populate is called, so the map does not receive any notification and doesn’t refresh itself).

Some things to check:

• Did you specify your api key for the MapView? *

*) How to specify your api key (in the layout resource for your activity):

<com.google.android.maps.MapView android:id="@+id/map"
    ...
    android:apiKey="your-api-key-here"/>