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gistfile1.js

var MainView = Backbone.View.extend({
		el: $('.js-messagesMainView'),
		events: {
			'change .js-statusFilterInput': 'filter',
			'click .js-checkboxFilterAll': 'filter'
		},
		initialize: function() {
			dialogsCollection.on('sync', function(e) {
				console.log(e);
				$('.preloader').hide();
			});
		},
		filter: function (e) {
			$('.preloader').show();
			var serialized = mainView.$('.js-statusFilterForm, #messagesSearchInput').serializeArray();
			dialogsCollection.fetch({
				method: 'post',
				data: serialized,
				reset: true
			});
			dialogsView.$el.html('');
		}
	});