Google Maps API 3

CHAPTER 9 ■ DEALING WITH MASSIVE NUMBERS OF MARKERS
The JavaScript
Start this example from the JavaScript code shown in Listing 9-6. It will create a map that’s zoomed
down somewhere in the middle of the United States.
Listing 9-6. The Starting JavaScript Code for Example 9-3
(function() {
window.onload = function() {
};
})();
// Creating a map
var options = {
zoom: 5,
center: new google.maps.LatLng(37.99, -93.77),
mapTypeId: google.maps.MapTypeId.ROADMAP
};
var map = new google.maps.Map(document.getElementById('map'), options);
Creating a MarkerManager Object
In the JavaScript file you’re now going to add code to create a MarkerManager object. You are then going
to create several markers at random locations and add these to the object.
Let’s start by creating a new MarkerManager object. In its simplest form, all you need to do is to pass
a reference to the map to it. You will insert this code right below the code that creates the map.
var mgr = new MarkerManager(map);
The MarkerManager constructor does have an optional second argument, which is an object literal
containing options for tweaking its default settings (see Table 9-7). For now, you will omit this and
settle with the default settings, but you will come back to the options object later in this chapter.
Table 9-7. Definition of the MarkerManager Constructor
Constructor
MarkerManager(map:Map, options?:Object)
Description
Creates an empty MarkerManager object
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