Google Maps API v3 remove all polylines

Question

Little background. I have a navigation setup for when you click on a certain navigation item, it creates markers on the map. If you click on a different navigation

Answer 1

You have to do polyline.setMap(null), that will remove the line from the map. Documentation.

Answer 2

polyline is just an array of LatLng objects, not individual Polylines. I think you probably need a separate array for the polylines, which you can then loop over to remove them all. Create a global array line.

 var line = [];
 polyline = new google.maps.Polyline({
        path: points,
        strokeColor: "#FF0000",
        strokeOpacity: 1.0,
        strokeWeight: 2
    });
 line.push(polyline);

Now you are pushing all the polyline objects into an array line. You can make it invisible or remove it from the map by looping it like this:

for (i=0; i<line.length; i++) 
{                           
  line[i].setMap(null); //or line[i].setVisible(false);
}