Itemized Overlays...Not drawing a collection but refreshing????

by Scott » Fri, 23 Apr 2010 08:05:14 GMT


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 'm trying to write code that draws accuracy circles around a gps
location based on a time param. I have no problem setting up the GPS,
or of calculating how to draw the circles...What's been killing me is
that the Overlays always overwrite one another...So I can never have
more than one circle...I've looked at all the examples and tutorials
online but they seem to be obsessed with putting in icons or with
Drawing from some database or array...If I understood correctly I
should be able to do itemizedoverlays and just draw as i go without
having to track each readout in an array....HELP WHAT AM I DOING
WRONG? PS This code also crashes if I touch the map now.

MY CLASS
public class HelloItemizedOverlay extends ItemizedOverlay {
private List items;
private Drawable marker;
public HelloItemizedOverlay() {
super(null);
items = new ArrayList();
}
@Override
protected OverlayItem createItem(int index) {
return (OverlayItem)items.get(index);
}
@Override
public int size() {
return items.size();
}
@Override
public void draw(Canvas canvas, MapView mapView, boolean shadow)
{
super.draw(canvas, mapView, shadow);
if (TempLat > 0) {
Point center = new Point();
Point left = new Point();
Point screenPts = new Point();
Projection projection = mapView.getProjection();
float[] result = new float[1];
Location.distanceBetween(TempLat, TempLon, TempLat,
TempLon +1, result);
float longitudeLineDistance = result[0];
GeoPoint leftGeo = new GeoPoint((int)(TempLat*1e6),(int)
((TempLon-TempAccy/longitudeLineDistance)*1e6));
projection.toPixels(leftGeo, left);
projection.toPixels(p, center);
int radius = center.x - left.x;
accuracyPaint.setAntiAlias(true);
accuracyPaint.setStrokeWidth(2.0f);
accuracyPaint.setColor(0xff6666ff);
accuracyPaint.setStyle(Style.STROKE);
canvas.drawCircle(center.x, center.y, radius,
accuracyPaint);
accuracyPaint.setColor(0x186666ff);
accuracyPaint.setStyle(Style.FILL);
canvas.drawCircle(center.x, center.y, radius,
accuracyPaint);
}
}
public void addItem(OverlayItem item) {
items.add(item);
populate();
}
}

MY ONCREATE INITIALIZATION CALL

super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mapView = (MapView) findViewById(R.id.myGMap);
LinearLayout zoomLayout = (LinearLayout)findViewById(R.id.zoom);
View zoomView = mapView.getZoomControls();
mapView.setSatellite(true);
zoomLayout.addView(zoomView,
new LinearLayout.LayoutParams(
LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT));
mapView.displayZoomControls(true);
mc = mapView.getController();
mc.setZoom(1;
accuracyPaint = new Paint();
overlay = new HelloItemizedOverlay();
......

MY ONLOCATIONCHANGED EVENT

public void onLocationChanged(Location location) {
MSGSTXT.setText("Location Found...");
TempTime = location.getTime();
TempLat = location.getLatitude();
TempLon = location.getLongitude();
TempAccy = location.getAccuracy();
TempSpeed = location.getSpeed();
TempBear = location.getBearing();
TempAlt = location.getAltitude();
p = new GeoPoint(
(int) (TempLat * 1E6),
(int