backbone.collectionsubset
Create sub-collections of other collections and keep them in sync.
tasks = # Create a subset of our main collection today = taskssubcollection : taskisTodaytoday.url = '/tasks/today' # Create a new task in the main collection... taskscreate id: 200today: true # ...and it's automatically pushed to all subsets todayget200 is tasksget200 # true # Model changes are pushed upwards todayget200destroy # Create models in subsets and they are pushed to the parent collection todaycreate id: 201todayget201 is tasksget2001 # true # And they will update on fetch tasksfetch # When subsets are fetched, all the models are pushed to the parent collection todayfetch
Getting Started
Download the production version or the development version.
In your web page:
Now you have two methods for creating subsets (or subcollections).
Collection::subcollection
The easiest way to create a subset is to use Collection::subcollection
var TaskCollection = BackboneCollection;var tasks = ;var today = tasks;
today
will be an instance of tasks.constructor
, in this case, TaskCollection
.
Backbone.CollectionSubset
If you need access to the subset object itself (you might want to modify the filter) you can create a subset directly.
var allTasks = ;var subset = parent: allTasks { return task; }; var todayTasks = subsetchild; subset;
Documentation
Depending on how you create the subset you have different interface. Creating a subcollection via Backbone.Collection::subcollection
you will only have
access to the child collection and the Backbone.CollectionSubset instance is completely transparent. However, you may need some extra flexibility so you can
also create Backbone.CollectionSubset
instances manually
subset = parent: tasks
vs.
new_collection = taskssubcollection : modelisToday
Options
refresh
- Whether to refresh the collection from the parent immediately. Defaults totrue
triggers
- Set which model attribute changes to watch for. This is important for performance. Defaults tonull
filter
- The default filter. By default lets all models passchild
- The collection to use for the child. This isn't required and will be automatically created. Defaults tonull
parent
- required The collection to base the subset on. Must be a Backbone.Collection.
Methods
If you create a Backbone.CollectionSubset instance directly you will have access to these methods.
setParent
Set the parent collection. Will unbind any events on the collection that the subset current has and setup all the events for syncing with the child collection
setChild
Same as the previous option, but with the child collection.
setFilter
Set the filter used on the parent collection. This does not automatically refresh the child collection.
refresh
Refreshes the child collection with models from the parent. Clears out the child collection and refilters the parent. Triggers a 'refresh' event on the child.
dispose
Clean up the subset. Removes the child collection completely and removes all events from the parent child. Triggers a dispose
event on the subset.
Todo
- Add url option to
subcollection
that will prepend the parent collection url
Contributing
In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using grunt.
Also, please don't edit files in the "dist" subdirectory as they are generated via grunt. You'll find source code in the "lib" subdirectory!
Release History
(Nothing yet)
License
Copyright (c) 2012 Anthony Short Licensed under the MIT license.