What is the best way to escape HTML on ExtJS application generally?

What is the best way to escape HTML on ExtJS application generally?

I am developing a web application using ExtJS to build GUI and communicate
with server via RESTful web-service (the returned data is formatted as
JSON objects).
Now I am having problems when processing with data which contains HTML
tags, Javascript codes inside; because when I set those values to Ext
forms, labels, input fields, they are affected by those syntaxes.
I used this function to load data from model object to form:
form.loadRecord(model);
I have found a solution to escape HTML and JS: using
field.setValue(Ext.util.Format.htmlDecode(data));
but I think that is not a good solution for whole application, because the
developers must do so much things: review all input fields, labels, and
put that snippet to them. And after all, that is not a beautiful way to
build a fast, robust and maintainable application.
So, could you please help me solution so that it can be modified at one
place, and affects to the rest. Can I override the setValue/ setLabel of
AbstractComponent? Or should I encode the data before rendering them? And
how to decode those data? (P/S: I uses Grails framework on the
server-side) Thank you so much.