This site is by no means the definitive guide to backbone.js and all corrections and contributions are welcome.
Follow @neutralthoughtsBackbone routers are used for routing your applications URL’s when using hash tags(#). In the traditional MVC sense they don’t neccesarily fit the semantics and if you have read “What is a view?” it will elaborate on this point. Though a Backbone “router” is still very useful for any application/feature that needs URL routing/history capabilities.
Defined routers should always contain at least one route and a function to map the particular route to. In the example below we are going to define a route that is always called.
Also note that routes intepret anything after “#” tag in the url. All links in your application should target “#/action” or “#action”. (Appending a forward slash after the hashtag looks a bit nicer e.g. http://example.com/#/user/help)
<script>
var AppRouter = Backbone.Router.extend({
routes: {
"*actions": "defaultRoute" // matches http://example.com/#anything-here
},
defaultRoute: function( actions ){
// The variable passed in matches the variable in the route definition "actions"
alert( actions );
}
});
// Initiate the router
var app_router = new AppRouter;
// Start Backbone history a neccesary step for bookmarkable URL's
Backbone.history.start();
</script>
<a href="#action">Activate route</a>
<a href="#/route/action">Activate another route</a>
<!-- Notice the change in the url -->
Please note: * Prior to Backbone 0.5 (released 1. July 2011) a Router was called a Controller. To avoid confusion, the Backbone developers changed the name to Router. Hence, if you find yourself using an older version of Backbone you should write Backbone.Controller.extend({ * });
Most conventional frameworks allow you to define routes that contain a mix of static and dynamic route parameters. For example you might want to retrieve a post with a variable id with a friendly URL string. Such that your URL would look like “http://example.com/#/posts/12”. Once this route was activated you would want to access the id given in the URL string. This example is implemented below.
<script>
var AppRouter = Backbone.Router.extend({
routes: {
"/posts/:id": "getPost",
"*actions": "defaultRoute" // Backbone will try match the route above first
},
getPost: function( id ) {
// Note the variable in the route definition being passed in here
alert( "Get post number " + id );
},
defaultRoute: function( actions ){
alert( actions );
}
});
// Instantiate the router
var app_router = new AppRouter;
// Start Backbone history a neccesary step for bookmarkable URL's
Backbone.history.start();
</script>
<a href="#/posts/120">Post 120</a>
<a href="#/posts/130">Post 130</a>
<!-- Notice the change in the url -->
Backbone uses two styles of variables when implementing routes. First there are “:params” which match any URL components between slashes. Then there are “*splats” which match any number of URL components. Note that due to the nature of a “*splat” it will always be the last variable in your URL as it will match any and all components.
Any “*splats” or “:params” in route definitions are passed as arguments (in respective order) to the associated function. A route defined as “/:route/:action” will pass 2 variables (“route” and “action”) to the callback function. (If this is confusing please post a comment and I will try articulate it better)
Here are some examples of using “:params” and “*splats”
routes: {
"/posts/:id": "getPost",
// <a href="http://example.com/#/posts/121">Example</a>
"/download/*path": "downloadFile",
// <a href="http://example.com/#/download/user/images/hey.gif">Download</a>
"/:route/:action": "loadView",
// <a href="http://example.com/#/dashboard/graph">Load Route/Action View</a>
},
getPost: function( id ){
alert(id); // 121
},
downloadFile: function( path ){
alert(path); // user/images/hey.gif
},
loadView: function( route, action ){
alert(route + "_" + action); // dashboard_graph
}
Routes are quite powerful and in an ideal world your application should never contain too many. If you need to implement hash tags with SEO in mind, do a google search for “google seo hashbangs”.
Remember to do a pull request for any errors you come across.
No Tips and Tricks
