You can pass values from trigger to listener using option argument (2nd) of trigger.
It'll be sent to your listener as third argument.
Code :
var Sidebar = Backbone.Model.extend({
setElementAttributes: function (value, cssAttribute) {
this.set({
property: value
}, {
cssAttribute: cssAttribute
});
}
});
window.sidebar = new Sidebar;
sidebar.on('change:property', function (model, value, options) {
console.log(options.cssAttribute);
});