Question

I’m trying to solve this issue with my constructor that gives me a duplicate method error:

import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Point;

import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;
import com.google.android.maps.Projection;


public class MapRouteOverlay extends Overlay {
private GeoPoint gp1;
private GeoPoint gp2;

private int mode=0;
private int defaultColor;

public MapRouteOverlay(GeoPoint gp1, GeoPoint gp2, int mode) { 
    this.gp1 = gp1;
    this.gp2 = gp2;
    this.mode = mode;
    defaultColor = 999;
}

public MapRouteOverlay(GeoPoint gp1, GeoPoint gp2, int defaultColor) { 
    this.gp1 = gp1;
    this.gp2 = gp2;
    this.mode = mode;
    this.defaultColor = defaultColor;
}

public int getMode() { 
    return mode;
}

public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) { 
    Projection projection = mapView.getProjection(); 
    if (shadow == false) { 
        Paint paint = new Paint();
        paint.setAntiAlias(true);
        Point point = new Point();
        projection.toPixels(gp1, point);

        if (mode==2) {
            if(defaultColor == 999)
                paint.setColor(Color.RED);
            else 
                paint.setColor(defaultColor);
            Point point2 = new Point();
            projection.toPixels(gp2, point2);
            paint.setStrokeWidth(5);
            paint.setAlpha(120);
            canvas.drawLine(point.x, point.y, point2.x, point2.y, paint);
        }
    }
    return super.draw(canvas, mapView, shadow, when);
}
}

The error I’m getting is this:
Duplicate method MapRouteOverlay(GeoPoint, GeoPoint, int) in type MapRouteOverlay

I want them to be constructors. How do I fix this so it works? Any help would be appreciated!

Answer 1

you dont satisfy the overloading rules.

public MapRouteOverlay(GeoPoint gp1, GeoPoint gp2, int mode) { 

you have a duplicate constructor with the same number and type of arguments.

Rules Of Method Overloading in java(applies to Constructors as well):

1. Must have different argument lists.
2. May Throw different exceptions
3. May have different return types(in case of method overloading)

you will have to change one of your constructor signatures like this:

public MapRouteOverlay( int mode,GeoPoint gp1, GeoPoint gp2) { 
      this(gp1,gp2, mode); //if your super class does not have an no-args constructor,this must be the first line in an overloaded constructor, a call to this() or super();
      //rest of your code.
  }