Collate Backbone collection success and errors - backbone.js

Question

I have two functions that loop through all models in a Backbone collection, and save those that have been changed, or destroy those that have been selected for deletion. What I need to do is collate the success and errors, so that I can notify "X number of changes/deletions were successful" and/or "There was an error changing/saving X number of domains".
I've no experience with saving/destroying Backbone collections, only models; and can't find anything on the internet that shows how to do this.
The save and remove are called by events in the parent view.
The relevant code:
App.Views.SiteDomains = Backbone.View.extend({
el: '.site-domains',
initialize: function() {
this.collection.on('all',this.render, this);
},
render: function() {
$('.site-domains').empty();
this.collection.each( function(model)
{
var view = new App.Views.SiteDomain({model: model});
this.$('.site-domains').append(view.render().el);
return this;
});
},
saveDomainChanges: function() {
this.collection.each( function(model)
{
var ref = model.get('ref');
if ($('#' + ref).val() != model.get('domain')) {
$('.save-domains').prop('disabled', true);
var fields = $(this.el).find('form').serializeArray(), data = {};
$.each(fields, function(i, pair)
{
data[pair.name] = pair.value;
});
model.save(data, {
wait:true,
success: function(model, response, event)
{
// Pass each success to notification function
},
error: function(model, response, event)
{
// Pass each error to notification function
}
});
}
});
$('.save-domains').prop('disabled', false);
},
removeDomain: function() {
this.collection.each( function(model)
{
var ref = model.get('ref');
if ($('#remove-' + ref).prop('checked'))
{
model.destroy({
wait:true,
success:function() {
// Pass each success to notification function
},
error: function() {
// Pass each error to notification function
}
});
}
});
}
});
Many, many, many thanks in advance to anyone that can help with this! :)

Answer 1

You could use an event aggregator and create Model/View or just POJO for the notifications according to your app design. Something like this:
// Event aggregator
App.vent = _.extend({}, Backbone.Events);
// POJO for the notifications
App.notifications = {
var onCreateSuccess = function (model, response) {
...
};
var onCreateError = function (model, response) {
...
};
App.vent.on('sitedomain:create:success', onCreateSuccess);
App.vent.on('sitedomain:create:error', onCreateError);
};
// Add event triggering to corresponding callbacks
model.save(data, {
wait:true,
success: function(model, response, event) {
App.vent.trigger('createdomain:create:success', model, response);
},
error: function(model, response, event) {
App.vent.trigger('createdomain:create:error', model, response);
}
});