Google Maps API v3: How to remove all markers?

Question

In Google Maps API v2, if I wanted to remove all the map markers, I could simply do:

map.clearOverlays();

How do I do this in Google Maps API v3?

Looking at the Reference API, it's unclear to me.

Answer 1

Just walk over markers and remove them from map, empty maps markers array after that:

var markers = map.markers;
for(var i = 0; i < markers.length; i++) {
    markers[i].setMap(null);
}
map.markers = [];

Answer 2

google.maps.Map.prototype.markers = new Array();

google.maps.Map.prototype.addMarker = function(marker) {
    this.markers[this.markers.length] = marker;
};

google.maps.Map.prototype.getMarkers = function() {
    return this.markers
};

google.maps.Map.prototype.clearMarkers = function() {
    for(var i=0; i<this.markers.length; i++){
        this.markers[i].setMap(null);
    }
    this.markers = new Array();
};

I don't think there is one in V3 so I used the above custom implementation.

Disclaimer: I did not write this code but I forgot to retain a reference when I merged it into my codebase so I don't know where it came from.

Answer 3

Simply do the following:

I. Declare a global variable:

var markersArray = [];

II. Define a function:

function clearOverlays() {
  for (var i = 0; i < markersArray.length; i++ ) {
    markersArray[i].setMap(null);
  }
  markersArray.length = 0;
}

OR

google.maps.Map.prototype.clearOverlays = function() {
  for (var i = 0; i < markersArray.length; i++ ) {
    markersArray[i].setMap(null);
  }
  markersArray.length = 0;
}

III. Push markers in the 'markerArray' before calling the following:

markersArray.push(marker);
google.maps.event.addListener(marker,"click",function(){});

IV. Call the clearOverlays(); or map.clearOverlays(); function wherever required.

That's it!!

Answer 4

A clean and easy application of rolinger's answer.

function placeMarkerAndPanTo(latLng, map) {
      while(markersArray.length) { markersArray.pop().setMap(null); }
      var marker = new google.maps.Marker({
        position: latLng,
        map: map
      });
      map.panTo(latLng);

      markersArray.push(marker) ;
    }

Answer 5

It seems that there is no such function in V3 yet.

People suggest to keep references to all markers you have on the map in an array. And then when you want to delete em all, just loop trough the array and call .setMap(null) method on each of the references.

See this question for more info/code.

My version:

google.maps.Map.prototype.markers = new Array();

google.maps.Map.prototype.getMarkers = function() {
    return this.markers
};

google.maps.Map.prototype.clearMarkers = function() {
    for(var i=0; i<this.markers.length; i++){
        this.markers[i].setMap(null);
    }
    this.markers = new Array();
};

google.maps.Marker.prototype._setMap = google.maps.Marker.prototype.setMap;

google.maps.Marker.prototype.setMap = function(map) {
    if (map) {
        map.markers[map.markers.length] = this;
    }
    this._setMap(map);
}

The code is edited version of this code http://www.lootogo.com/googlemapsapi3/markerPlugin.html I removed the need to call addMarker manually.

Pros

• Doing this way you keep the code compact and in one place (doesn't pollute the namespace).
• You don't have to keep track of the markers yourself anymore you can always find all the markers on the map by calling map.getMarkers()

Cons

• Using prototypes and wrappers like I did now makes my code dependent on Google code, if they make a mayor change in their source this will break.
• If you don't understand it then you won't be able to fix it if does break. The chances are low that they're going to change anything which will break this, but still..
• If you remove one marker manually, it's reference will still be in markers array. (You could edit my setMap method to fix it, but at the cost of looping trough markers array and removing the reference)

Answer 6

This was the most simple of all the solutions originally posted by YingYang Mar 11 '14 at 15:049 under the original response to the users original question

I am using his same solution 2.5 years later with google maps v3.18 and it works like a charm

markersArray.push(newMarker) ;
while(markersArray.length) { markersArray.pop().setMap(null); }

// No need to clear the array after that.