How to interact to iframe content using javascript?

[will]

Have you read this thread:

PlayCanvas Hosting and postMessage

I’m experimenting with javascript’s postMessage command with PlayCanvas. (see code below). All I am doing in the code below is loading a PlayCanvas app into an iframe and using a button on the host page to send a message to the PlayCanvas app. When the app recieves the message it hides/shows the 3D object. This works fine when I download the PlayCanvas app code and web host it in IIS. The problem comes when I try to send a message to a app hosted on PlayCanvas. (It’s unclear if we want to …