Hi, it's already been a little while since the last reply to this post but I'd like to share what I did in this regard (Localization) with my project.
I started referring to all the localizable strings by a variable name:
And then I created a file for every language in the application with the translations:
var header = Ext.create( 'Ext.TitleBar',
id: 'header', docked: 'top', title: titleName, cls: '', html: htmlHeaderContent
Then in the html file I can either check the language of the browser, or create a language selection screen, and decide which file to load.
var titleName="English title";
var htmlHeaderContent="Html content in English";
var titleName="Título español";
var htmlHeaderContent="Contenido en español";
I find this way pretty easy to use and maintain.