backbone-dnode
Version:
Persistant backbone storage through dnode pub/sub
288 lines (233 loc) • 8.31 kB
JavaScript
// An example Backbone application contributed by
// [Jérôme Gravel-Niquet](http://jgn.me/). This demo uses a simple
// [LocalStorage adapter](backbone-localstorage.html)
// to persist Backbone models within your browser.
// Load the application once the DOM is ready, using `jQuery.ready`:
$(function(){
// Todo Model
// ----------
// Our basic **Todo** model has `content`, `order`, and `done` attributes.
window.Todo = Backbone.Model.extend({
// Server communication settings
url : 'todos',
type : 'todo',
sync : _.sync,
idAttribute: '_id',
// Default attributes for the todo.
defaults: {
content: "empty todo...",
done: false
},
// Ensure that each todo created has `content`.
initialize: function() {
if (!this.get("content")) {
this.set({"content": this.defaults.content});
}
},
// Toggle the `done` state of this todo item.
toggle: function() {
this.save({done: !this.get("done")});
},
// Remove this Todo from *localStorage* and delete its view.
clear: function() {
this.destroy();
this.view.remove();
}
});
// Todo Collection
// ---------------
// The collection of todos is backed by *localStorage* instead of a remote
// server.
window.TodoList = Backbone.Collection.extend({
// Reference to this collection's model.
model: Todo,
// Server communication settings
// Save all of the todo items under the `"todos"` namespace.
url : 'todos',
type : 'todo',
sync : _.sync,
idAttribute: '_id',
// Filter down the list of all todo items that are finished.
done: function() {
return this.filter(function(todo){ return todo.get('done'); });
},
// Filter down the list to only todo items that are still not finished.
remaining: function() {
return this.without.apply(this, this.done());
},
// We keep the Todos in sequential order, despite being saved by unordered
// GUID in the database. This generates the next order number for new items.
nextOrder: function() {
if (!this.length) return 1;
return this.last().get('order') + 1;
},
// Todos are sorted by their original insertion order.
comparator: function(todo) {
return todo.get('order');
}
});
// Create our global collection of **Todos**.
window.Todos = new TodoList;
// Todo Item View
// --------------
// The DOM element for a todo item...
window.TodoView = Backbone.View.extend({
//... is a list tag.
tagName: "li",
// Cache the template function for a single item.
template: _.template($('#item-template').html()),
// The DOM events specific to an item.
events: {
"click .check" : "toggleDone",
"dblclick div.todo-content" : "edit",
"click span.todo-destroy" : "clear",
"keypress .todo-input" : "updateOnEnter"
},
// The TodoView listens for changes to its model, re-rendering. Since there's
// a one-to-one correspondence between a **Todo** and a **TodoView** in this
// app, we set a direct reference on the model for convenience.
initialize: function() {
_.bindAll(this, 'render', 'close');
this.model.bind('remove', this.remove);
this.model.bind('change', this.render);
this.model.view = this;
},
// Re-render the contents of the todo item.
render: function() {
$(this.el).html(this.template(this.model.toJSON()));
this.setContent();
return this;
},
// To avoid XSS (not that it would be harmful in this particular app),
// we use `jQuery.text` to set the contents of the todo item.
setContent: function() {
var content = this.model.get('content');
this.$('.todo-content').text(content);
this.input = this.$('.todo-input');
this.input.bind('blur', this.close);
this.input.val(content);
},
// Toggle the `"done"` state of the model.
toggleDone: function() {
this.model.toggle();
},
// Switch this view into `"editing"` mode, displaying the input field.
edit: function() {
$(this.el).addClass("editing");
this.input.focus();
},
// Close the `"editing"` mode, saving changes to the todo.
close: function() {
this.model.save({content: this.input.val()});
$(this.el).removeClass("editing");
},
// If you hit `enter`, we're through editing the item.
updateOnEnter: function(e) {
if (e.keyCode == 13) this.close();
},
// Remove this view from the DOM.
remove: function() {
if (this.view) {
this.view.remove();
}
$(this.el).remove();
},
// Remove the item, destroy the model.
clear: function() {
this.model.clear();
}
});
// The Application
// ---------------
// Our overall **AppView** is the top-level piece of UI.
window.AppView = Backbone.View.extend({
// Instead of generating a new element, bind to the existing skeleton of
// the App already present in the HTML.
el: $("#todoapp"),
// Our template for the line of statistics at the bottom of the app.
statsTemplate: _.template($('#stats-template').html()),
// Delegated events for creating new items, and clearing completed ones.
events: {
"keypress #new-todo": "createOnEnter",
"keyup #new-todo": "showTooltip",
"click .todo-clear a": "clearCompleted"
},
// At initialization we bind to the relevant events on the `Todos`
// collection, when items are added or changed. Kick things off by
// loading any preexisting todos that might be saved in *localStorage*.
initialize: function() {
_.bindAll(this, 'addOne', 'addAll', 'render');
this.input = this.$("#new-todo");
Todos.bind('add', this.addOne);
Todos.bind('reset', this.addAll);
Todos.bind('all', this.render);
Todos.bind('subscribe', function(data) {
console.log('subscribed', data);
});
Todos.bind('unsubscribe', function(data) {
console.log('subscribed', data);
});
Todos.subscribe();
Todos.fetch();
},
// Re-rendering the App just means refreshing the statistics -- the rest
// of the app doesn't change.
render: function() {
var done = Todos.done().length;
this.$('#todo-stats').html(this.statsTemplate({
total: Todos.length,
done: Todos.done().length,
remaining: Todos.remaining().length
}));
},
// Add a single todo item to the list by creating a view for it, and
// appending its element to the `<ul>`.
addOne: function(todo) {
var view = new TodoView({model: todo});
this.$("#todo-list").append(view.render().el);
},
// Add all items in the **Todos** collection at once.
addAll: function() {
Todos.each(this.addOne);
},
// Generate the attributes for a new Todo item.
newAttributes: function() {
return {
content: this.input.val(),
order: Todos.nextOrder(),
done: false
};
},
// If you hit return in the main input field, create new **Todo** model,
// persisting it to *localStorage*.
createOnEnter: function(e) {
if (e.keyCode != 13) return;
Todos.create(this.newAttributes());
this.input.val('');
},
// Clear all done todo items, destroying their models.
clearCompleted: function() {
_.each(Todos.done(), function(todo){ todo.clear(); });
return false;
},
// Lazily show the tooltip that tells you to press `enter` to save
// a new todo item, after one second.
showTooltip: function(e) {
var tooltip = this.$(".ui-tooltip-top");
var val = this.input.val();
tooltip.fadeOut();
if (this.tooltipTimeout) clearTimeout(this.tooltipTimeout);
if (val == '' || val == this.input.attr('placeholder')) return;
var show = function(){ tooltip.show().fadeIn(); };
this.tooltipTimeout = _.delay(show, 1000);
}
});
// Finally, we kick things off by creating the **App**.
DNode()
.use(dnodeBackbone({
pubsub: true
}))
.connect(_.once(function() {
window.App = new AppView;
}));
});