Example: Help me load the code below in a div. (id="ja-content-main")

Ext.application({
name: 'HelloExt',
launch: function() {
Ext.create('Ext.container.Viewport', {
layout: 'anchor',
autoEl: 'center',

items: [
{
title: 'Hello Ext',
html : 'This is to test Ext JS.'
}
]
});
}
});