@ -14,4 +14,4 @@ In Flux, the Dispatcher is a singleton that directs the flow of data and ensures
When a user interacts with a React view, the view sends an action (usually represented as a JavaScript object with some fields) through the dispatcher, which notifies the various stores that hold the application's data and business logic. When the stores change state, they notify the views that something has updated. This works especially well with React's declarative model, which allows the stores to send updates without specifying how to transition views between states.
Flux is more of a pattern than a formal framework, so you can start using Flux immediately without a lot of new code. An [example of this architecture](https://github.com/facebook/react/tree/master/examples/todomvc-flux) is available, along with more [detailed documentation](http://facebook.github.io/react/docs/flux-overview.html) and a [tutorial](http://facebook.github.io/react/docs/flux-todo-list.html). Look for more examples to come in the future.
Flux is more of a pattern than a formal framework, so you can start using Flux immediately without a lot of new code. An [example of this architecture](https://github.com/facebook/flux/tree/master/examples/flux-todomvc) is available, along with more [detailed documentation](http://facebook.github.io/react/docs/flux-overview.html) and a [tutorial](http://facebook.github.io/react/docs/flux-todo-list.html). Look for more examples to come in the future.
@ -51,7 +51,7 @@ As an application grows, the dispatcher becomes more vital, as it can manage dep
Stores contain the application state and logic. Their role is somewhat similar to a model in a traditional MVC, but they manage the state of many objects — they are not instances of one object. Nor are they the same as Backbone's collections. More than simply managing a collection of ORM-style objects, stores manage the application state for a particular __domain__ within the application.
For example, Facebook's [Lookback Video Editor](https://facebook.com/lookback/edit) utilized a TimeStore that kept track of the playback time position and the playback state. On the other hand, the same application's ImageStore kept track of a collection of images. The TodoStore in our [TodoMVC example](https://github.com/facebook/react/tree/master/examples/todomvc-flux) is similar in that it manages a collection of to-do items. A store exhibits characteristics of both a collection of models and a singleton model of a logical domain.
For example, Facebook's [Lookback Video Editor](https://facebook.com/lookback/edit) utilized a TimeStore that kept track of the playback time position and the playback state. On the other hand, the same application's ImageStore kept track of a collection of images. The TodoStore in our [TodoMVC example](https://github.com/facebook/flux/tree/master/examples/flux-todomvc) is similar in that it manages a collection of to-do items. A store exhibits characteristics of both a collection of models and a singleton model of a logical domain.
As mentioned above, a store registers itself with the dispatcher and provides it with a callback. This callback receives the action's data payload as a parameter. The payload contains a type attribute, identifying the action's type. Within the store's registered callback, a switch statement based on the action's type is used to interpret the payload and to provide the proper hooks into the store's internal methods. This allows an action to result in an update to the state of the store, via the dispatcher. After the stores are updated, they broadcast an event declaring that their state has changed, so the views may query the new state and update themselves.
@ -76,7 +76,7 @@ Actions may also come from other places, such as the server. This happens, for e
### What About that Dispatcher?
As mentioned earlier, the dispatcher is also able to manage dependencies between stores. This functionality is available through the `waitFor()` method within the Dispatcher class. We did not need to use this method within the extremely simple [TodoMVC application](https://github.com/facebook/react/tree/master/examples/todomvc-flux), but we have included it [in the example dispatcher](https://github.com/facebook/react/blob/master/examples/todomvc-flux/js/dispatcher/Dispatcher.js#L110) as an example of what a dispatcher should be able to do in a larger, more complex application.
As mentioned earlier, the dispatcher is also able to manage dependencies between stores. This functionality is available through the `waitFor()` method within the Dispatcher class. We did not need to use this method within the extremely simple [TodoMVC application](https://github.com/facebook/flux/tree/master/examples/flux-todomvc), but we have included it [in the example dispatcher](https://github.com/facebook/flux/blob/master/examples/flux-todomvc/js/dispatcher/Dispatcher.js#L110) as an example of what a dispatcher should be able to do in a larger, more complex application.
Within the TodoStore's registered callback we could explicitly wait for any dependencies to first update before moving forward:
To demonstrate the Flux architecture with some example code, let's take on the classic TodoMVC application. The entire application is available in the React GitHub repo within the [todomvc-flux](https://github.com/facebook/react/tree/master/examples/todomvc-flux) example directory, but let's walk through the development of it a step at a time.
To demonstrate the Flux architecture with some example code, let's take on the classic TodoMVC application. The entire application is available in the Flux GitHub repo within the [flux-todomvc](https://github.com/facebook/flux/tree/master/examples/flux-todomvc) example directory, but let's walk through the development of it a step at a time.
To begin, we'll need some boilerplate and get up and running with a module system. Node's module system, based on CommonJS, will fit the bill very nicely and we can build off of [react-boilerplate](https://github.com/petehunt/react-boilerplate) to get up and running quickly. Assuming you have npm installed, simply clone the react-boilerplate code from GitHub, and navigate into the resulting directory in Terminal (or whatever CLI application you like). Next run the npm scripts to get up and running: `npm install`, then `npm run build`, and lastly `npm start` to continuously build using Browserify.
The TodoMVC example has all this built into it as well, but if you're starting with react-boilerplate make sure you edit your package.json file to match the file structure and dependencies described in the TodoMVC example's [package.json](https://github.com/facebook/react/tree/master/examples/todomvc-flux/package.json), or else your code won't match up with the explanations below.
The TodoMVC example has all this built into it as well, but if you're starting with react-boilerplate make sure you edit your package.json file to match the file structure and dependencies described in the TodoMVC example's [package.json](https://github.com/facebook/flux/tree/master/examples/flux-todomvc/package.json), or else your code won't match up with the explanations below.
Source Code Structure
@ -137,7 +137,7 @@ Now we've created an implementation that is a bit more specific to our needs, wi
Creating Stores
----------------
We can use Node's EventEmitter to get started with a store. We need EventEmitter to broadcast the 'change' event to our controller-views. So let's take a look at what that looks like. I've omitted some of the code for the sake of brevity, but for the full version see [TodoStore.js](https://github.com/Facebook/react/blob/master/examples/todomvc-flux/js/stores/TodoStore.js) in the TodoMVC example code.
We can use Node's EventEmitter to get started with a store. We need EventEmitter to broadcast the 'change' event to our controller-views. So let's take a look at what that looks like. I've omitted some of the code for the sake of brevity, but for the full version see [TodoStore.js](https://github.com/Facebook/flux/blob/master/examples/flux-todomvc/js/stores/TodoStore.js) in the TodoMVC example code.
```javascript
var AppDispatcher = require('../dispatcher/AppDispatcher');
@ -236,7 +236,7 @@ Another important part is the registration of the store's callback with the disp
Listening to Changes with a Controller-View
-------------------------------------------
We need a React component near the top of our component hierarchy to listen for changes in the store. In a larger app, we would have more of these listening components, perhaps one for every section of the page. In Facebook's Ads Creation Tool, we have many of these controller-like views, each governing a specific section of the UI. In the Lookback Video Editor, we only had two: one for the animated preview and one for the image selection interface. Here's one for our TodoMVC example. Again, this is slightly abbreviated, but for the full code you can take a look at the TodoMVC example's [TodoApp.react.js](https://github.com/facebook/react/blob/master/examples/todomvc-flux/js/components/TodoApp.react.js)
We need a React component near the top of our component hierarchy to listen for changes in the store. In a larger app, we would have more of these listening components, perhaps one for every section of the page. In Facebook's Ads Creation Tool, we have many of these controller-like views, each governing a specific section of the UI. In the Lookback Video Editor, we only had two: one for the animated preview and one for the image selection interface. Here's one for our TodoMVC example. Again, this is slightly abbreviated, but for the full code you can take a look at the TodoMVC example's [TodoApp.react.js](https://github.com/facebook/flux/blob/master/examples/flux-todomvc/js/components/TodoApp.react.js)
Paul O’Shannessy
11 years ago