Last updated 26 June 2015. Created on 26 June 2015.
Edited by hutch. Log in to edit this page.

Here is an example demonstrating the use of 'bounds_changed' in javascript.
It assumes your map id is 'key_1', that you have a page identifier class 'view-display-id-page'
and that 'show maplinks' is enabled in the view. Any markers that fall outside the viewport will be hidden in the list of links.
Edit 'mytheme_script' to whatever suits your needs.

(function ($) {
  Drupal.behaviors.mytheme_script = {
    attach: function () {
      var k = 'key_1';
      var page_id = 'view-display-id-page';
      if ($('.' + page_id).is('div') && $("#getlocations_map_wrapper_" + k).is('div')) {
        var map = Drupal.getlocations_map[k];
        google.maps.event.addListener(map, 'bounds_changed', function() {
          b = map.getBounds();
          data = Drupal.getlocations_data[k];
          latlons = data.latlons;
          for (var i = 0; i < latlons.length; i++) {
            var arr2 = latlons[i];
            var lat = arr2[0];
            var lon = arr2[1];
            var lid = arr2[2];
            var p = new google.maps.LatLng(lat, lon);
            // is this point within the bounds?
            if (b.contains(p)) {
              $("li a.lid-" + lid).show();
            }
            else {
              $("li a.lid-" + lid).hide();
            }
          }
        });
      }
    } // end attach
  }; // end behaviors
})(jQuery);

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