How to remove all the polylines from a map
Following
How to draw a path between two markers
I had to add lot of polylines between two markers, to make a path.
One of the markers is draggable, lets say source is draggable.
So, when user starts dragging the marker, the path previously drawn must be erased and a new path between new source and destination must be draw.
I am able to draw the new path, but how can i erase the previous path?
This is how the path is drawn:
for (int z = 0; z < list.size() - 1; z++) {
LatLng src = list.get(z);
LatLng dest = list.get(z + 1);
Polyline line = map.addPolyline(new PolylineOptions()
.add(new LatLng(src.latitude, src.longitude),
new LatLng(dest.latitude, dest.longitude))
.width(2).color(Color.RED).geodesic(true));
}
One solution i can get is
map.clear();
To clear all the polylines, markers etc.. and add the markers again, then drawn the path.
But as soon as I start dragging, the marker is cleared, hence not visible on the map :(
Thank You
Keep track of the Polyline as you add it to the map:
Polyline polyline = this.mMap.addPolyline(new PolylineOptions().....);
Then when you want to remove it:
polyline.remove();
If you have lots of Polylines, just add them to a List as they are put on the map:
List<Polyline> polylines = new ArrayList<Polyline>();
for(....)
{
polylines.add(this.mMap.addPolyline(new PolylineOptions()....));
}
And when you want to delete:
for(Polyline line : polylines)
{
line.remove();
}
polylines.clear();
The key is to keep a reference to the Polyline objects and call .remove() on each one.
I know this is very old question but I noticed that this is very common need. I found another way and I wanted to share it.
Here is the basic idea:
Polyline polylineFinal;
PolylineOptions polylineOptions;
loop {
polylineOptions.add( new LatLng( latitude, longitude ) );
}
polylineOptions.width(2);
polylineOptions.color(Color.RED);
polylineOptions.geodesic(true);
polylineFinal = map.addPolyline (polylineOptions);
Map's "addPolyline" method returns a single polyline which contains all the points. When I need to remove the points, I call polylineFinal's "remove" method.
polylineFinal.remove();
Update
If you want to removes all markers, polylines, polygons, overlays, etc from the map use
mMap.clear(); //it will remove all additional objects from map
and if you only want to remove all or single polyline, polygon, marker etc see @DiskDev Answer above. In this case you must keep track of every single additional object you add to map