Circular Dependencies for a web app using backbone

问题:

I am in the following situation.

I am using requireJs to loads module and I don't want to use global variables.

The main.js is responsible to load the router.
Then the router loads the app and the app loads several subApps.

After everything has been initialised, the subApps needs the router for making router.navigate.

Here the schema:

main.js -> router -> app -> subApp -> router

Then I have a problem of Circular Dependencies and for that reason the router in subApp will be undefined.

What is the best way to reorganise my code or to fix this problem? Are there some example about this?

回答1:

the schema:

 main.js -> router -> app -> subApp -> router

is right.

If you are using backbone.marionette, in order to access the router from the app and subApp, without using global var, you should start the app in router in this way:

---

// router.js
YourApp.start(router: router);

---

// app.js
YourApp.addInitializer(function(options){
  // do useful stuff here
  var myView = new MyView({
    router: options.router
  });
  YourApp.mainRegion.show(myView);
});

回答2:

Subapp can raise events which router handles rather than having an explicit dependency on router

回答3:

In my project, I use the following dependency: main.js -> app -> router -> subApp.

In app.js, I create a single global variable that holds a pointer to my app:

define([...], function(...) {
return {
  initialize: function() {
    window.MyApp = new Backbone.Marionette.Application();
    // ...
    MyApp.start();
  }
};
});

This makes it extremely easy to access my app's regions from anywhere, as well as store global state information in one name space.

I tried doing it without the global app at first, but eventually gave up and found this approach to be a lot more flexible.