Delaying execution of Javascript function relative to Google Maps / geoxml3 parser?
- by Terra Fimeira
I'm working on a implementing a Google map on a website with our own tiles overlays and KML elements. I've been previously requested to create code so that, for instance, when the page is loaded from a specific URL, it would initialize with one of the tile overlays already enabled. Recently, I've been requested to do the same for the buildings which are outlined by KML elements so that, arriving at the page with a specific URL, it would automatically zoom, center, and display information on the building.
However, while starting with the tile overlays work, the building KML does not. After doing some testing, I've determined that when the code which checks the URL executes, the page is still loading the KML elements and thus do not exist for the code to compare to or use:
Code for evaluating URL (placed at the end of onLoad="initialize()")
function urlClick() {
var currentURL = window.location.href; //Retrieve page URL
var URLpiece = currentURL.slice(-6); //pull the last 6 digits (for testing)
if (URLpiece === "access") { //If the resulting string is "access":
access_click(); //Display accessibility overlay
} else if (URLpiece === "middle") { //Else if the string is "middle":
facetClick('Middle College'); //Click on building "Middle College"
};
};
facetClick();
function facetClick(name) { //Convert building name to building ID.
for (var i = 0; i < active.placemarks.length; i++) {
if (active.placemarks[i].name === name) {
sideClick(i) //Click building whose id matches "Middle College"
};
};
};
Firebug Console Error
active is null
for (var i = 0; i < active.placemarks.length; i++) {
active.placemarks is which KML elements are loaded on the page, and being null, means no KML has been loaded yet. In short, I have a mistiming and I can't seem to find a suitable place to place the URL code to execute after the KMl has loaded. As noted above, I placed it at the end of onLoad="initialize()", but it would appear that, instead of waiting for the KML to completely load earlier in the function, the remainder of the function is executed:
onLoad="initialize()"
information(); //Use the buttons variables inital state to set up description
buttons(); //and button state
button_hover(0); //and button description to neutral.
//Create and arrange the Google Map.
//Create basic tile overlays.
//Set up parser to work with KML elements.
myParser = new geoXML3.parser({ //Parser: Takes KML and converts to JS.
map: map, //Applies parsed KML to the map
singleInfoWindow: true,
afterParse: useTheData //Allows us to use the parsed KML in a function
});
myParser.parse(['/maps/kml/shapes.kml','/maps/kml/shapes_hidden.kml']);
google.maps.event.addListener(map, 'maptypeid_changed', function() {
autoOverlay();
});
//Create other tile overlays to appear over KML elements.
urlClick();
I suspect one my issues lies in using the geoxml3 parser (http://code.google.com/p/geoxml3/) which converts our KML files to Javascript. While the page has completed loading all of the elements, the map on the page is still loading, including the KML elements. I have also tried placing urlClick() in the parser itself in various places which appear to execute after all the shapes have been parsed, but I've had no success there either.
While I've been intending to strip out the parser, I would like to know if there is any way of executing the "urlClick" after the parser has returned the KML shapes. Ideally, I don't want to use an arbitrary means of defining a time to wait, such as "wait 3 seconds, and go", as my various browsers all load the page at different times; rather, I'm looking for some way to say "when the parser is done, execute" or "when the Google map is completely loaded, execute" or perhaps even "hold until the parser is complete before advancing to urlClick".
