multiple overlayitems not visible on mapview in android

here is the code that i am using in my Activity to show multiple markers on the mapview. i have used a customoverlay class which extends itemizedoverlays. Here is the code for that class:

public class view1CustomOverlays extends ItemizedOverlay<OverlayItem> {

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

    boolean isClickable = false;
    Context context = null;
    Drawable orangeMarker = null;

    public view1CustomOverlays(Drawable defaultMarker, Context c,
            boolean isActive, Drawable inActiveMarker) {
        super(boundCenterBottom(defaultMarker));
        context = c;
        isClickable = isActive;
        orangeMarker = inActiveMarker;
    }

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

    @Override
    protected OverlayItem createItem(int i) {
        return mOverlays.get(i);
    }

    @Override
    public int size() {
        return mOverlays.size();
    }
}

i am using this class in the main UI activity. Here is how i am using this class to add overlays to my mapview:

UPDATE

priva开发者_如何学JAVAte void view1LoadDataOnMap(String[] poleCord) {
    try {
        Drawable redFlag = getResources().getDrawable(R.drawable.red);
        Drawable greenFlag = getResources().getDrawable(R.drawable.green);
        Drawable orangeFlag = getResources().getDrawable(R.drawable.orange);
        int noOfPoles = poleCord.length / 4;
        List<Overlay> list = map.getOverlays();
        list.clear();
        view1CustomOverlays customOverlay = null;
        for (int i = 0; i < noOfPoles; i=i+4) {
            Float lat = Float.parseFloat(poleCord[i]);
            Float lng = Float.parseFloat(poleCord[i+1]);
            String poleNumber = poleCord[i+2];
            String ticketId = poleCord[i+3];
            customOverlay = new view1CustomOverlays(greenFlag, this, true,
                    orangeFlag);
            GeoPoint p = new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6));
            OverlayItem overlayItem = new OverlayItem(p, poleNumber, null);
            customOverlay.addOverlay(overlayItem);
            Log.i("adding overlay",overlayItem.toString());
        }
        list.add(customOverlay);
    } catch (NumberFormatException e) {
        e.printStackTrace();
    } catch (NotFoundException e) {
        e.printStackTrace();
    }

}

Only one overlayitem is showing on the screen. What could be the problem. i have checked that there are several overlayitems being added to my class but when i add to the class to my mapview only one overlayitem is being drawn.

There are in total 81 markers that i need to add on the map. So i am making 81 overlayitems and adding them to the overlay and adding the overlay once at the end.

thank you in advance.

You are missing:

myMap.getOverLays().add(customOverlay);

In

private void view1LoadDataOnMap(String[] poleCord) {
    try {
        Drawable redFlag = getResources().getDrawable(R.drawable.red);
        Drawable greenFlag = getResources().getDrawable(R.drawable.green);
        Drawable orangeFlag = getResources().getDrawable(R.drawable.orange);
        int noOfPoles = poleCord.length / 4;
        List<Overlay> list = map.getOverlays();
        list.clear();
        view1CustomOverlays customOverlay = null;
        for (int i = 0; i < noOfPoles; i++) {
            Float lat = Float.parseFloat(poleCord[0]);
            Float lng = Float.parseFloat(poleCord[1]);
            String poleNumber = poleCord[2];
            String ticketId = poleCord[3];
            customOverlay = new view1CustomOverlays(greenFlag, this, true,
                    orangeFlag);
            GeoPoint p = new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6));
            OverlayItem overlayItem = new OverlayItem(p, poleNumber, null);
            customOverlay.addOverlay(overlayItem);
            myMap.getOverLays().add(customOverlay);
            Log.i("adding overlay",overlayItem.toString());
        }
        list.add(customOverlay);
    } catch (NumberFormatException e) {
        e.printStackTrace();
    } catch (NotFoundException e) {
        e.printStackTrace();
    }

}

Irrespective of the noOfPoles, you keep on adding elements 0,1,2 and 3. You probably have multiple markers but they're all in the same place. You need to make it a function of 'i'

like

for (int i = 0; i < noOfPoles; i++) {
            Float lat = Float.parseFloat(poleCord[ i * 4]);
            Float lng = Float.parseFloat(poleCord[i * 4 + 1]);
            String poleNumber = poleCord[i * 4 + 2];
            String ticketId = poleCord[i * 4 + 3];
            ....
}