I have been looking for a while now, and cannot find good information about how to localize the standard components.
I have been trying these kind of approaches:
        Ext.apply(Ext.MessageBox, {
            OK    : {text: 'OK',     itemId: 'ok',  ui: 'action'},
            YES   : {text: 'Oui',    itemId: 'yes', ui: 'action'},
            NO    : {text: 'Non',     itemId: 'no'},
            CANCEL: {text: 'Annuler', itemId: 'cancel'},

            INFO    : Ext.baseCSSPrefix + 'msgbox-info',
            WARNING : Ext.baseCSSPrefix + 'msgbox-warning',
            QUESTION: Ext.baseCSSPrefix + 'msgbox-question',
            ERROR   : Ext.baseCSSPrefix + 'msgbox-error',

            OKCANCEL: [
                {text: 'Annuler', itemId: 'cancel'},
                {text: 'OK',     itemId: 'ok',  ui : 'action'}
            YESNOCANCEL: [
                {text: 'Annuler', itemId: 'cancel'},
                {text: 'Non',     itemId: 'no'},
                {text: 'Oui',    itemId: 'yes', ui: 'action'}
            YESNO: [
                {text: 'Non',  itemId: 'no'},
                {text: 'Oui', itemId: 'yes', ui: 'action'}
I call this code from my Application 'launch' method.
Is it the correct way of doing this?
If so, is it the right place to do so?

1) This methods works for my message boxes except the one that pops up from the 'onUpdated' method in my application. Is it a matter of timing of the Ext.apply ?

2) I cannot apply this method for the Ext.picker.Picker doneButton and cancelButton:
        Ext.apply(Ext.picker.Picker, {
          doneButton: 'Ok',
          cancelButton: 'Annuler'
This doesn't work...

Is there any good resource about how to do proper localization ?