Appended Iframe listeners are not working

I'm relatively new to ExtJS and I'm trying to append an Iframe with listeners to the DOM. But unfortunately the listeners are not working. Both console.logs are not printing anything. What am I doing wrong. I hope someone can help.

My ExtJS Version is 4.2.2.

Code:

Ext.DomHelper.append(container.getEl().dom.id, {
            tag: 'iframe',
            frameBorder: 0,
            width: 0,
            height: 0,
            css: 'display:none;visibility:hidden;height:0px;',
            src: urls[y],
            listeners: {
                afterrender: function () {
                    console.log('rendered');
                    this.getEl().on('load', function () {
                        console.log('loaded');
                    });
                }
            }
        }

Kevin



Appended Iframe listeners are not working