iframe height change listener

gistfile1.js

// in parent document
// no jQuery required
(function () {
	var
	ifr = document.getElementById('iframeid'),
	vpadding = 50;
	window.addEventListener(
		"message",
		function (ev) {
			var d=ev.data.split(':'), k=d[0], v=d[1];
			console.log(d);
			switch (k) {
				case 'h' :
					ifr.setAttribute('height', ((v-0)+vpadding)+'px');
					break;
			}
		},
		ifr
	);
})();


// call in child when height changes
function sendHeight ()
{
	if (!parent) {
		return;
	}
	parent.postMessage('h:'+$('body').height(), '*');
};