I have a game in heroku, now I\'m trying to make it work in Facebook canvas, but, while it works in Firefox, in Chrome and IE doesn\'t.
IE shows a warning with a but
My issue was I was instatiating the player completely from start but I used an iframe instead of a wrapper div.
In my case SSL certificate was invalid for iframe domain, so make sure that iframe URL you're trying to send messages to is opening w/o any issues (in case you load your iframe over https
).
Another reason this could be happening is if you are using an iframe that has the sandbox attribute and allow-same-origin
isn't set e.g.:
// page.html
<iframe id="f" src="http://localhost:8000/iframe.html" sandbox="allow-scripts"></iframe>
<script type="text/javascript">
var f = document.getElementById("f").contentWindow;
// will throw exception
f.postMessage("hello world!", 'http://localhost:8000');
</script>
// iframe.html
<script type="text/javascript">
window.addEventListener("message", function(event) {
console.log(event);
}, false);
</script>
I haven't found a solution other than:
f.postMessage("hello world!", '*');
Make sure the target window that you (or Facebook) is posting a message to, has completed loading. Most of the times I've gotten this error were when an iframe I was sending messages to had failed to load.
In my case I didn't add the http://
prefix. Potentially worth checking.
To check whether the frame have been loaded, use onload function. Or put your main function in load: I recommend to use load when creating the iframe by js
$('<iframe />', {
src: url,
id: 'receiver',
frameborder: 1,
load:function(){
//put your code here, so that those code can be make sure to be run after the frame loaded
}
}).appendTo('body');