Map Overlays of custom shape and color in Android

This post covers the way to add some custom Map Overlays of custom shape, lets say circle with some custom color in it.


package com.your.package;

import java.util.ArrayList;

import android.R.color;
import android.app.AlertDialog;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.graphics.Point;
import android.graphics.drawable.Drawable;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.ItemizedOverlay;
import com.google.android.maps.MapView;
import com.google.android.maps.OverlayItem;
import com.google.android.maps.Projection;

public class LocationOverlay extends ItemizedOverlay<OverlayItem> {

   private Context mContext;
   private ArrayList<OverlayItem> mOverlays = new ArrayList<OverlayItem>();
   private int outerCircleColorCode = 0xFF7600;

   /** Paint for drawing the overlay circle. */
   private Paint mCirclePaint;

   /** Represents screen co-ordinates. */
   private final Point mScreenCoords = new Point();

   /** Halo color. */
   private int mHaloColor;

   /** Halo border color. */
   private int mHaloBorderColor;
   private GeoPoint childLocation;

   public LocationOverlay(Drawable arg0, Context context, GeoPoint childLocation) {
      super(boundCenterBottom(arg0));
      mContext = context;
      this.childLocation = childLocation;
   }

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

   @Override
   protected OverlayItem createItem(int arg0) {
      return mOverlays.get(arg0);
   }

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

   @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;
   }

   @Override
   public void draw(Canvas canvas, MapView mapView, boolean arg2) {
      final Projection projection = mapView.getProjection();

      projection.toPixels(childLocation, mScreenCoords);

      double radiusInMeter = 100;
      final float radius = projection.metersToEquatorPixels((float) radiusInMeter);
      //Inner white circle
      mCirclePaint = new Paint();
      mCirclePaint.setAntiAlias(true);
      // Draw semi-transparent circle.
      mCirclePaint.setAlpha(50);
      mCirclePaint.setColor(Color.WHITE);
      mCirclePaint.setStyle(Style.STROKE);
      mCirclePaint.setStrokeWidth(12);

      canvas.drawCircle(mScreenCoords.x, mScreenCoords.y, radius-1, mCirclePaint);
     
      //Outer while circle
      mCirclePaint = new Paint();
      mCirclePaint.setAntiAlias(true);
      // Draw semi-transparent circle.
      mCirclePaint.setAlpha(10);
      mCirclePaint.setColor(Color.WHITE);
      mCirclePaint.setStyle(Style.STROKE);
      mCirclePaint.setStrokeWidth(12);

      canvas.drawCircle(mScreenCoords.x, mScreenCoords.y, radius+1, mCirclePaint);

      mCirclePaint.setColor(outerCircleColorCode); //Orange Color
      mCirclePaint.setStyle(Style.STROKE);
      mCirclePaint.setAlpha(255);
      mCirclePaint.setStrokeWidth(8);
      canvas.drawCircle(mScreenCoords.x, mScreenCoords.y, radius, mCirclePaint);
   }

}