File: app/js/app-extensions/app-content.js
/**
`Y.App` extension that provides pjax-style content fetching and handling.
@module app
@submodule app-content
@since 3.7.0
**/
var PjaxContent = Y.PjaxContent;
/**
`Y.App` extension that provides pjax-style content fetching and handling.
This makes it easy to fetch server rendered content for URLs using Ajax. The
HTML content returned from the server will be view-ified and set as the app's
main content, making it seamless to use a mixture of server and client rendered
views.
When the `"app-content"` module is used, it will automatically mix itself into
`Y.App`, and it provides three main features:
- **`Y.App.Content.route`**: A stack of middleware which forms a pjax-style
content route.
- **`loadContent()`**: Route middleware which load content from a server. This
makes an Ajax request for the requested URL, parses the returned content and
puts it on the route's response object.
- **`showContent()`**: Method which provides an easy way to view-ify HTML
content which should be shown as an app's active/visible view.
The following is an example of how these features can be used:
// Creates a new app and registers the `"post"` view.
var app = new Y.App({
views: {
post: {type: Y.PostView}
}
});
// Uses a simple server rendered content route for the About page.
app.route('/about/', Y.App.Content.route);
// Uses the `loadContent()` middleware to fetch the contents of the post
// from the server and shows that content in a `"post"` view.
app.route('/posts/:id/', 'loadContent', function (req, res, next) {
this.showContent(res.content.node, {view: 'post'});
});
@class App.Content
@uses PjaxContent
@extensionfor App
@since 3.7.0
**/
function AppContent() {
PjaxContent.apply(this, arguments);
}
/**
A stack of middleware which forms a pjax-style content route.
This route will load the rendered HTML content from the server, then create and
show a new view using those contents.
@property route
@type Array
@static
@since 3.7.0
**/
AppContent.route = ['loadContent', '_contentRoute'];
AppContent.prototype = {
// -- Public Methods -------------------------------------------------------
/**
Sets this app's `activeView` attribute using the specified `content`.
This provides an easy way to view-ify HTML content which should be shown as
this app's active/visible view. This method will determine the appropriate
view `container` node based on the specified `content`. By default, a new
`Y.View` instance will be created unless `options.view` is specified.
Under the hood, this method calls the `showView()` method, so refer to its
docs for more information.
@method showContent
@param {HTMLElement|Node|String} content The content to show, it may be
provided as a selector string, a DOM element, or a `Y.Node` instance.
@param {Object} [options] Optional objects containing any of the following
properties in addition to any `showView()` options:
@param {Object|String} [options.view] The name of a view defined in this
app's `views`, or an object with the following properties:
@param {String} options.view.name The name of a view defined in this
app's `views`.
@param {Object} [options.view.config] Optional configuration to use when
creating the new view instance. This config object can also be used
to update an existing or preserved view's attributes when
`options.update` is `true`. **Note:** If a `container` is specified,
it will be overridden by the `content` specified in the first
argument.
@param {Function} [callback] Optional callback function to call after the
new `activeView` is ready to use. **Note:** this will override
`options.callback` and it can be specified as either the second or third
argument. The function will be passed the following:
@param {View} callback.view A reference to the new `activeView`.
@chainable
@since 3.7.0
@see App.showView()
**/
showContent: function (content, options, callback) {
// Makes sure we have a node instance, and will query selector strings.
content = Y.one(content);
// Support the callback function being either the second or third arg.
if (typeof options === 'function') {
options = {callback: options};
callback = null;
}
// Mix in default option to *not* render the view because presumably we
// have pre-rendered content here. This also creates a copy so we can
// modify the object.
options = Y.merge({render: false}, options);
var view = options.view || '',
viewName = typeof view === 'string' ? view : view.name,
viewConfig = typeof view !== 'string' ? view.config : {},
viewInfo = this.getViewInfo(viewName),
container, template, type, ViewConstructor;
// Remove `view` from the `options` which will be passed along to the
// `showView()` method.
delete options.view;
// When the specified `content` is a document fragment, we want to see
// if it only contains a single node, and use that as the content. This
// checks `childNodes` which will include text nodes.
if (content && content.isFragment() &&
content.get('childNodes').size() === 1) {
content = content.get('firstChild');
}
// When the `content` is an element node (`nodeType` 1), we can use it
// as-is for the `container`. Otherwise, we'll construct a new container
// based on the `options.view`'s `containerTemplate`.
if (content && content.get('nodeType') === 1) {
container = content;
} else {
type = (viewInfo && viewInfo.type) || Y.View;
// Looks for a namespaced constructor function on `Y`.
ViewConstructor = typeof type === 'string' ?
Y.Object.getValue(Y, type.split('.')) : type;
// Find the correct node template for the view.
template = ViewConstructor.prototype.containerTemplate;
container = Y.Node.create(template);
// Append the document fragment to the newly created `container`
// node. This is the worst case where we have to create a wrapper
// node around the `content`.
container.append(content);
}
// Makes sure the view is created using _our_ `container` node.
viewConfig = Y.merge(viewConfig, {container: container});
// Finally switch to the new `activeView`. We want to make sure `view`
// is a string if it's falsy, that way a new view will be created.
return this.showView(viewName, viewConfig, options, callback);
},
// -- Protected Methods ----------------------------------------------------
/**
Provides a default content route which will show a server rendered view.
**Note:** This route callback assumes that it's called after the
`loadContent()` middleware.
@method _contentRoute
@param {Object} req Request object.
@param {Object} res Response Object.
@param {Function} next Function to pass control to the next route callback.
@protected
@since 3.7.0
@see Y.App.Content.route
**/
_contentRoute: function (req, res, next) {
var content = res.content,
doc = Y.config.doc,
activeViewHandle;
// We must have some content to work with.
if (!(content && content.node)) { return next(); }
if (content.title && doc) {
// Make sure the `activeView` does actually change before we go
// messing with the page title.
activeViewHandle = this.onceAfter('activeViewChange', function () {
doc.title = content.title;
});
}
this.showContent(content.node);
// Detach the handle just in case.
if (activeViewHandle) {
activeViewHandle.detach();
}
next();
}
};
// Mix statics.
AppContent.ATTRS = Y.Attribute.protectAttrs(PjaxContent.ATTRS);
// Mix prototype.
Y.mix(AppContent, PjaxContent, false, null, 1);
// -- Namespace ----------------------------------------------------------------
Y.App.Content = AppContent;
Y.Base.mix(Y.App, [AppContent]);