DFP post-rendering callback

Question

I need to trigger some JavaScript after DFP has finished rendering all the ads on the page - or at least when it has triggered collapseEmptyDivs (which

Answer 1

I'm pretty sure that DFP doesn't provide for a callback after the ad has rendered. I have used the following code to do this. It calls the callback function after one of the following has happened:

-The ad has loaded and the iframe has rendered

-No ad was loaded, and the ad unit was hidden by collapseEmptyDivs()

-A certain amount of time has passed (in this case, 2 seconds) with neither one happening. Like if there was some sort of network error connecting to DFP.

adId would be the id of your ad container

assumes you are using jQuery

function callback() {
   //your callback function - do something here
}

function getIframeHtml(iframe) {
   if(iframe.contentWindow && iframe.contentWindow.document && iframe.contentWindow.document.body && iframe.contentWindow.document.body.innerHTML) {
       return iframe.contentWindow.document.body.innerHTML;
   }
   return null;
}

var dfpNumChecks = 20;
var dfpCheckCount = 0;
var dfpCheckTimer = 100;

function dfpLoadCheck(adId) {
   var nodes = document.getElementById(adId).childNodes;

   if(nodes.length && nodes[0].nodeName.toLowerCase() == 'iframe' && getIframeHtml(nodes[0])) {
       //the iframe for the ad has rendered
       callback();
       return;
   } else if($('#' + adId).css('display') == 'none' || (dfpCheckCount >= dfpNumChecks)) {
       //the ad unit has been hidden by collapseEmptyDivs()
       callback();
       return;
   } else {
       dfpCheckCount++;
       setTimeout(function() { dfpLoadCheck(adId) }, dfpCheckTimer); 
   }
}