static/ext/src/ux/grid/filter/NumericFilter.js
function () {
        var values = this.getValue(),
            key;
        for (key in values) {
            if (values[key] !== undefined) {
                return true;
            }
        }
        return false;
    }
function () {
        var values = this.getValue(),
            key;
        for (key in values) {
            if (values[key] !== undefined) {
                return true;
            }
        }
        return false;
    }
Template method that is to return <tt>true</tt> if the filter
has enough configuration information to be activated.
@return {Boolean}