source : ng-map-pool.js 

  1. /**
  2.  * @ngdoc factory
  3.  * @name NgMapPool
  4.  * @description
  5.  *   Provide map instance to avoid memory leak
  6.  */
  7. (function() {
  8.   'use strict';
  9.   /**
  10.    * @memberof NgMapPool
  11.    * @desc map instance pool
  12.    */
  13.   var mapInstances = [];
  14.   var $window, $document, $timeout;
  15.   var add = function(el) {
  16.     var mapDiv = $document.createElement("div");
  17.     mapDiv.style.width = "100%";
  18.     mapDiv.style.height = "100%";
  19.     el.appendChild(mapDiv);
  20.     var map = new $window.google.maps.Map(mapDiv, {});
  21.     mapInstances.push(map);
  22.     return map;
  23.   };
  24.   var findById = function(el, id) {
  25.     var notInUseMap;
  26.     for (var i=0; i<mapInstances.length; i++) {
  27.       var map = mapInstances[i];
  28.       if (map.id == id && !map.inUse) {
  29.         var mapDiv = map.getDiv();
  30.         el.appendChild(mapDiv);
  31.         notInUseMap = map;
  32.         break;
  33.       }
  34.     }
  35.     return notInUseMap;
  36.   };
  37.   var findUnused = function(el) { //jshint ignore:line
  38.     var notInUseMap;
  39.     for (var i=0; i<mapInstances.length; i++) {
  40.       var map = mapInstances[i];
  41.       if (map.id) {
  42.         continue;
  43.       }
  44.       if (!map.inUse) {
  45.         var mapDiv = map.getDiv();
  46.         el.appendChild(mapDiv);
  47.         notInUseMap = map;
  48.         break;
  49.       }
  50.     }
  51.     return notInUseMap;
  52.   };
  53.   /**
  54.    * @memberof NgMapPool
  55.    * @function getMapInstance
  56.    * @param {HtmlElement} el map container element
  57.    * @return map instance for the given element
  58.    */
  59.   var getMapInstance = function(el) {
  60.     var map = findById(el, el.id) || findUnused(el);
  61.     if (!map) {
  62.       map = add(el);
  63.     } else {
  64.       /* firing map idle event, which is used by map controller */
  65.       $timeout(function() {
  66.         google.maps.event.trigger(map, 'idle');
  67.       }, 100);
  68.     }
  69.     map.inUse = true;
  70.     return map;
  71.   };
  72.   /**
  73.    * @memberof NgMapPool
  74.    * @function returnMapInstance
  75.    * @param {Map} an instance of google.maps.Map
  76.    * @desc sets the flag inUse of the given map instance to false, so that it 
  77.    * can be reused later
  78.    */
  79.   var returnMapInstance = function(map) {
  80.     map.inUse = false;
  81.   };
  82.   /**
  83.    * @memberof NgMapPool
  84.    * @function resetMapInstances
  85.    * @desc resets mapInstance array
  86.    */
  87.   var resetMapInstances = function() {
  88.     for(var i = 0;i < mapInstances.length;i++) {
  89.         mapInstances[i] = null;
  90.     }
  91.     mapInstances = [];
  92.   };
  93.   /**
  94.    * @memberof NgMapPool
  95.    * @function deleteMapInstance
  96.    * @desc delete a mapInstance
  97.    */
  98.   var deleteMapInstance= function(mapId) {
  99. 	  for( var i=0; i<mapInstances.length; i++ ) {
  100. 		  if( (mapInstances[i] !== null) && (mapInstances[i].id == mapId)) {
  101. 			  mapInstances[i]= null;
  102. 			  mapInstances.splice( i, 1 );
  103. 		  }
  104. 	  }
  105.   };
  106.   var NgMapPool = function(_$document_, _$window_, _$timeout_) {
  107.     $document = _$document_[0], $window = _$window_, $timeout = _$timeout_;
  108.     return {
  109. 	  mapInstances: mapInstances,
  110.       resetMapInstances: resetMapInstances,
  111.       getMapInstance: getMapInstance,
  112.       returnMapInstance: returnMapInstance,
  113.       deleteMapInstance: deleteMapInstance
  114.     };
  115.   };
  116.   NgMapPool.$inject = [ '$document', '$window', '$timeout'];
  117.   angular.module('ngMap').factory('NgMapPool', NgMapPool);
  118. })();