Sample Backbone.Router use case for backbone.routefilter (https://github.com/boazsender/backbone.routefilter)

sample-backbone.routefilter-router.js

/*
* This code does not actually work, it is for demonstration purposes
* of a router using https://github.com/boazsender/backbone.routefilter
*/

// Imagine this came from the server into a big app wide state object
// (likely a Backbone.Model if we were actually doing this for real).
var data = {
  // Here are my app's pages (it's content heavy app)
  "pages": [{
      "name": "page1",
      "id": 1,
      "layout": "list",
      "content": { ... }
    },
    {
      "name": "page2",
      "id": 12,
      "layout": "list",
      "content": { ... }
    }
  ],
  // Here is my bottom navigation
  "navigationbar": [
    {
      "text": "page1",
      "icon": "../img/coolicon1.png",
      "route": "page1"
    },
    {
      "text": "page2",
      "icon": "../img/coolicon1.png",
      "route": "page2"
    },
    {
      "text": "page3",
      "icon": "../img/coolicon3.png",
      "route": "page3"
    }
  ]
}

// Make a new collection and add the pages to it, so we can
// use .where to check an arbitrary route against a node's name
var pages = new Backbone.Collection();
pages.add( data.pages );

// Setup our router just like normal
var Router = Backbone.Router.extend({
  // set our route table with only one wild card route
  routes: {
    "": "index",
    "*path": "page"
  },
  // Use the backbone.routefilter before filter
  before: function( route ){
    // If the route is falsey, then we're at "/", pass
    if(!route){
      return;
    }

    // If the route arg does not exist as a named page in our
    // app data object then we have a problem. 
    // decodeURI in case there is a space in the page/route name
    if( pages.where({ name: decodeURI(route) }).length ){
      
      // Render a content not found page using a view we made somewhere else.
      var view = new NotFoundView({ model: page });
      view.render();

      // return false  to prevent the page callback from running.
      return false;
    }
  },
  index: function( route ){
    // Call some view we made somewhere else and render it
    var view = new IndexView();
    view.render();
  }
  // This callback will run for every page. It wont run if before
  // returns false.
  page: function( route ){
    // Get the page from the route
    // decodeURI in case there is a space in the page/route name
    var page = pages.where({ name: decodeURI(route) })[0];

    // Call some view we made somewhere else and render it
    var view = new PageView({ model: page });
    view.render();
 }
});

return Router;