App.Base Class
Provides a top-level application component which manages navigation and views.
This gives you a foundation and structure on which to build your application; it combines robust URL navigation with powerful routing and flexible view management.
Constructor
App.Base
-
[config]
Parameters:
-
[config]
Object optionalThe following are configuration properties that can be specified in addition to default attribute values and the non-attribute properties provided by
Y.Base
:-
[views]
Object optionalHash of view-name to metadata used to declaratively describe an application's views and their relationship with the app and other views. The views specified here will override any defaults provided by the
views
object on theprototype
.
-
Item Index
Methods
- addAttr
- addAttrs
- addTarget
- after
- attachEvents
- attrAdded
- before
- bubble
- create
- createView
- destroy
- detach
- detachAll
- detachEvents
- dispatch
- fire
- get
- getAttrs
- getEvent
- getPath
- getTargets
- getViewInfo
- hasRoute
- init
- match
- modifyAttr
- navigate
- on
- once
- onceAfter
- param
- parseType
- publish
- remove
- removeAttr
- removeQuery
- removeRoot
- removeTarget
- render
- replace
- reset
- route
- save
- set
- setAttrs
- showView
- subscribe deprecated
- toString
- unsubscribe deprecated
- unsubscribeAll deprecated
- upgrade
Properties
- containerTemplate
- events
- name deprecated
- template
- views
Attributes
Methods
addAttr
-
name
-
config
-
lazy
Adds an attribute with the provided configuration to the host object.
The config argument object supports the following properties:
- value <Any>
- The initial value to set on the attribute
- valueFn <Function | String>
-
A function, which will return the initial value to set on the attribute. This is useful for cases where the attribute configuration is defined statically, but needs to reference the host instance ("this") to obtain an initial value. If both the value and valueFn properties are defined, the value returned by the valueFn has precedence over the value property, unless it returns undefined, in which case the value property is used.
valueFn can also be set to a string, representing the name of the instance method to be used to retrieve the value.
- readOnly <boolean>
- Whether or not the attribute is read only. Attributes having readOnly set to true cannot be modified by invoking the set method.
- writeOnce <boolean> or <string>
-
Whether or not the attribute is "write once". Attributes having writeOnce set to true,
can only have their values set once, be it through the default configuration,
constructor configuration arguments, or by invoking set.
The writeOnce attribute can also be set to the string "initOnly", in which case the attribute can only be set during initialization (when used with Base, this means it can only be set during construction)
- setter <Function | String>
-
The setter function used to massage or normalize the value passed to the set method for the attribute. The value returned by the setter will be the final stored value. Returning Attribute.INVALID_VALUE, from the setter will prevent the value from being stored.
setter can also be set to a string, representing the name of the instance method to be used as the setter function.
- getter <Function | String>
-
The getter function used to massage or normalize the value returned by the get method for the attribute. The value returned by the getter function is the value which will be returned to the user when they invoke get.
getter can also be set to a string, representing the name of the instance method to be used as the getter function.
- validator <Function | String>
-
The validator function invoked prior to setting the stored value. Returning false from the validator function will prevent the value from being stored.
validator can also be set to a string, representing the name of the instance method to be used as the validator function.
- lazyAdd <boolean>
- Whether or not to delay initialization of the attribute until the first call to get/set it. This flag can be used to over-ride lazy initialization on a per attribute basis, when adding multiple attributes through the addAttrs method.
The setter, getter and validator are invoked with the value and name passed in as the first and second arguments, and with the context ("this") set to the host object.
Configuration properties outside of the list mentioned above are considered private properties used internally by attribute, and are not intended for public use.
Parameters:
-
name
StringThe name of the attribute.
-
config
ObjectAn object with attribute configuration property/value pairs, specifying the configuration for the attribute.
NOTE: The configuration object is modified when adding an attribute, so if you need to protect the original values, you will need to merge the object.
-
lazy
Boolean(optional) Whether or not to add this attribute lazily (on the first call to get/set).
Returns:
A reference to the host object.
addAttrs
-
cfgs
-
values
-
lazy
Configures a group of attributes, and sets initial values.
NOTE: This method does not isolate the configuration object by merging/cloning. The caller is responsible for merging/cloning the configuration object if required.
Parameters:
-
cfgs
ObjectAn object with attribute name/configuration pairs.
-
values
ObjectAn object with attribute name/value pairs, defining the initial values to apply. Values defined in the cfgs argument will be over-written by values in this argument unless defined as read only.
-
lazy
BooleanWhether or not to delay the intialization of these attributes until the first call to get/set. Individual attributes can over-ride this behavior by defining a lazyAdd configuration property in their configuration. See addAttr.
Returns:
A reference to the host object.
addTarget
-
o
Registers another EventTarget as a bubble target. Bubble order is determined by the order registered. Multiple targets can be specified.
Events can only bubble if emitFacade is true.
Included in the event-custom-complex submodule.
Parameters:
-
o
EventTargetthe target to add
after
-
type
-
fn
-
[context]
-
[arg*]
Subscribe to a custom event hosted by this object. The supplied callback will execute after any listeners add via the subscribe method, and after the default function, if configured for the event, has executed.
Parameters:
Returns:
A subscription handle capable of detaching the subscription
attachEvents
-
[events]
Attaches delegated event handlers to this view's container element. This
method is called internally to subscribe to events configured in the
events
attribute when the view is initialized.
You may override this method to customize the event attaching logic.
Parameters:
-
[events]
Object optionalHash of events to attach. See the docs for the
events
attribute for details on the format. If not specified, this view'sevents
property will be used.
attrAdded
-
name
Checks if the given attribute has been added to the host
Parameters:
-
name
StringThe name of the attribute to check.
Returns:
true if an attribute with the given name has been added, false if it hasn't. This method will return true for lazily added attributes.
before
()
Executes the callback before a DOM event, custom event or method. If the first argument is a function, it is assumed the target is a method. For DOM and custom events, this is an alias for Y.on.
For DOM and custom events: type, callback, context, 0-n arguments
For methods: callback, object (method host), methodName, context, 0-n arguments
Returns:
detach handle
bubble
-
evt
Propagate an event. Requires the event-custom-complex module.
Parameters:
-
evt
CustomEventthe custom event to propagate
Returns:
the aggregated return value from Event.Custom.fire
create
-
[container]
Creates and returns a container node for this view.
By default, the container is created from the HTML template specified in the
containerTemplate
property, and is not added to the DOM automatically.
You may override this method to customize how the container node is created
(such as by rendering it from a custom template format). Your method must
return a Y.Node
instance.
Parameters:
-
[container]
HTMLElement | Node | String optionalSelector string,
Y.Node
instance, or DOM element to use at the container node.
Returns:
Node instance of the created container node.
createView
-
name
-
[config]
Creates and returns a new view instance using the provided name
to look up
the view info metadata defined in the views
object. The passed-in config
object is passed to the view constructor function.
This function also maps a view instance back to its view info metadata.
Parameters:
Returns:
The new view instance.
destroy
-
[options]
Destroys this View, detaching any DOM events and optionally also destroying its container node.
By default, the container node will not be destroyed. Pass an options
object with a truthy remove
property to destroy the container as well.
detach
-
type
-
fn
-
context
Detach one or more listeners the from the specified event
Parameters:
-
type
String | ObjectEither the handle to the subscriber or the type of event. If the type is not specified, it will attempt to remove the listener from all hosted events.
-
fn
FunctionThe subscribed function to unsubscribe, if not supplied, all subscribers will be removed.
-
context
ObjectThe custom object passed to subscribe. This is optional, but if supplied will be used to disambiguate multiple listeners that are the same (e.g., you subscribe many object using a function that lives on the prototype)
Returns:
the host
detachAll
-
type
Removes all listeners from the specified event. If the event type is not specified, all listeners from all hosted custom events will be removed.
Parameters:
-
type
StringThe type, or name of the event
detachEvents
()
chainable
Detaches DOM events that have previously been attached to the container by
attachEvents()
.
dispatch
()
chainable
Dispatches to the first route handler that matches the current URL, if any.
If dispatch()
is called before the ready
event has fired, it will
automatically wait for the ready
event before dispatching. Otherwise it
will dispatch immediately.
fire
-
type
-
arguments
Fire a custom event by name. The callback functions will be executed from the context specified when the event was created, and with the following parameters.
The first argument is the event type, and any additional arguments are passed to the listeners as parameters. If the first of these is an object literal, and the event is configured to emit an event facade, that object is mixed into the event facade and the facade is provided in place of the original object.
If the custom event object hasn't been created, then the event hasn't been published and it has no subscribers. For performance sake, we immediate exit in this case. This means the event won't bubble, so if the intention is that a bubble target be notified, the event must be published on this object first.
Parameters:
-
type
String | ObjectThe type of the event, or an object that contains a 'type' property.
-
arguments
Object*an arbitrary set of parameters to pass to the handler. If the first of these is an object literal and the event is configured to emit an event facade, the event facade will replace that parameter after the properties the object literal contains are copied to the event facade.
Returns:
True if the whole lifecycle of the event went through, false if at any point the event propagation was halted.
get
-
name
Returns the current value of the attribute. If the attribute has been configured with a 'getter' function, this method will delegate to the 'getter' to obtain the value of the attribute.
Parameters:
-
name
StringThe name of the attribute. If the value of the attribute is an Object, dot notation can be used to obtain the value of a property of the object (e.g.
get("x.y.z")
)
Returns:
The value of the attribute
getAttrs
-
attrs
Gets multiple attribute values.
Parameters:
Returns:
An object with attribute name/value pairs.
getEvent
-
type
-
prefixed
Returns the custom event of the provided type has been created, a falsy value otherwise
Parameters:
Returns:
the custom event or null
getTargets
()
Returns an array of bubble targets for this object.
Returns:
EventTarget[]
getViewInfo
-
view
Returns the metadata associated with a view instance or view name defined on
the views
object.
Returns:
The metadata for the view, or undefined
if the view is
not registered.
hasRoute
-
url
Returns true
if this router has at least one route that matches the
specified URL, false
otherwise. This also checks that any named param
handlers also accept app param values in the url
.
This method enforces the same-origin security constraint on the specified
url
; any URL which is not from the same origin as the current URL will
always return false
.
Parameters:
-
url
StringURL to match.
Returns:
true
if there's at least one matching route, false
otherwise.
init
-
cfg
Init lifecycle method, invoked during construction. Sets up attributes and invokes initializers for the class hierarchy.
Parameters:
-
cfg
ObjectObject with configuration property name/value pairs
Returns:
A reference to this object
match
-
path
Returns an array of route objects that match the specified URL path.
If this router has a root
, then the specified path
must be
semantically within the root
path to match any routes.
This method is called internally to determine which routes match the current path whenever the URL changes. You may override it if you want to customize the route matching logic, although this usually shouldn't be necessary.
Each returned route object has the following properties:
-
callback
: A function or a string representing the name of a function this router that should be executed when the route is triggered. -
keys
: An array of strings representing the named parameters defined in the route's path specification, if any. -
path
: The route's path specification, which may be either a string or a regex. -
regex
: A regular expression version of the route's path specification. This regex is used to determine whether the route matches a given path.
Parameters:
-
path
StringURL path to match. This should be an absolute path that starts with a slash: "/".
Returns:
Array of route objects that match the specified path.
Example:
router.route('/foo', function () {});
router.match('/foo');
// => [{callback: ..., keys: [], path: '/foo', regex: ...}]
modifyAttr
-
name
-
config
Updates the configuration of an attribute which has already been added.
The properties which can be modified through this interface are limited to the following subset of attributes, which can be safely modified after a value has already been set on the attribute:
- readOnly;
- writeOnce;
- broadcast; and
- getter.
Note: New attributes cannot be added using this interface. New attributes must be added using addAttr, or an appropriate manner for a class which utilises Attributes (e.g. the ATTRS property in Base).
on
-
type
-
fn
-
[context]
-
[arg*]
Subscribe a callback function to a custom event fired by this object or from an object that bubbles its events to this object.
this.on("change", this._onChange, this);
Callback functions for events published with emitFacade = true
will
receive an EventFacade
as the first argument (typically named "e").
These callbacks can then call e.preventDefault()
to disable the
behavior published to that event's defaultFn
. See the EventFacade
API for all available properties and methods. Subscribers to
non-emitFacade
events will receive the arguments passed to fire()
after the event name.
To subscribe to multiple events at once, pass an object as the first argument, where the key:value pairs correspond to the eventName:callback.
this.on({
"attrChange" : this._onAttrChange,
"change" : this._onChange
});
You can also pass an array of event names as the first argument to subscribe to all listed events with the same callback.
this.on([ "change", "attrChange" ], this._onChange);
Returning false
from a callback is supported as an alternative to
calling e.preventDefault(); e.stopPropagation();
. However, it is
recommended to use the event methods whenever possible.
Parameters:
Returns:
A subscription handle capable of detaching that subscription
once
-
type
-
fn
-
[context]
-
[arg*]
Listen to a custom event hosted by this object one time.
This is the equivalent to on
except the
listener is immediatelly detached when it is executed.
Parameters:
Returns:
A subscription handle capable of detaching the subscription
onceAfter
-
type
-
fn
-
[context]
-
[arg*]
Listen to a custom event hosted by this object one time.
This is the equivalent to after
except the
listener is immediatelly detached when it is executed.
Parameters:
Returns:
A subscription handle capable of detaching that subscription
param
-
name
-
handler
Adds a handler for a route param specified by name.
Param handlers can be registered via this method and are used to
validate/format values of named params in routes before dispatching to the
route's handler functions. Using param handlers allows routes to defined
using string paths which allows for req.params
to use named params, but
still applying extra validation or formatting to the param values parsed
from the URL.
If a param handler regex or function returns a value of false
, null
,
undefined
, or NaN
, the current route will not match and be skipped. All
other return values will be used in place of the original param value parsed
from the URL.
Parameters:
-
name
StringName of the param used in route paths.
-
handler
Function | RegExpFunction to invoke or regular expression to
exec()
during route dispatching whose return value is used as the new param value. Values offalse
,null
,undefined
, orNaN
will cause the current route to not match and be skipped. When a function is specified, it will be invoked in the context of this instance with the following parameters:
Example:
router.param('postId', function (value) {
return parseInt(value, 10);
});
router.param('username', /^\w+$/);
router.route('/posts/:postId', function (req) {
Y.log('Post: ' + req.params.id);
});
router.route('/users/:username', function (req) {
// req.params.username
is an array because the result of calling
// exec()
on the regex is assigned as the param's value.
Y.log('User: ' + req.params.username[0]);
});
router.route('*', function () {
Y.log('Catch-all no routes matched!');
});
// URLs which match routes:
router.save('/posts/1'); // => "Post: 1"
router.save('/users/ericf'); // => "User: ericf"
// URLs which do not match routes because params fail validation:
router.save('/posts/a'); // => "Catch-all no routes matched!"
router.save('/users/ericf,rgrove'); // => "Catch-all no routes matched!"
parseType
-
type
-
[pre]
Takes the type parameter passed to 'on' and parses out the various pieces that could be included in the type. If the event type is passed without a prefix, it will be expanded to include the prefix one is supplied or the event target is configured with a default prefix.
Parameters:
Returns:
an array containing:
- the detach category, if supplied,
- the prefixed event type,
- whether or not this is an after listener,
- the supplied event type
publish
-
type
-
opts
Creates a new custom event of the specified type. If a custom event by that name already exists, it will not be re-created. In either case the custom event is returned.
Parameters:
-
type
Stringthe type, or name of the event
-
opts
Objectoptional config params. Valid properties are:
-
[broadcast=false]
Boolean optionalwhether or not the YUI instance and YUI global are notified when the event is fired.
-
[bubbles=true]
Boolean optionalWhether or not this event bubbles. Events can only bubble if
emitFacade
is true. -
[context=this]
Object optionalthe default execution context for the listeners.
-
[defaultFn]
Function optionalthe default function to execute when this event fires if preventDefault was not called.
-
[emitFacade=false]
Boolean optionalwhether or not this event emits a facade.
-
[prefix]
String optionalthe prefix for this targets events, e.g., 'menu' in 'menu:click'.
-
[fireOnce=false]
Boolean optionalif an event is configured to fire once, new subscribers after the fire will be notified immediately.
-
[async=false]
Boolean optionalfireOnce event listeners will fire synchronously if the event has already fired unless
async
istrue
. -
[preventable=true]
Boolean optionalwhether or not
preventDefault()
has an effect. -
[preventedFn]
Function optionala function that is executed when
preventDefault()
is called. -
[queuable=false]
Boolean optionalwhether or not this event can be queued during bubbling.
-
[silent]
Boolean optionalif silent is true, debug messages are not provided for this event.
-
[stoppedFn]
Function optionala function that is executed when stopPropagation is called.
-
[monitored]
Boolean optionalspecifies whether or not this event should send notifications about when the event has been attached, detached, or published.
-
[type]
String optionalthe event type (valid option if not provided as the first parameter to publish).
-
Returns:
the custom event
remove
()
chainable
Removes this view's container element from the DOM (if it's in the DOM), but doesn't destroy it or any event listeners attached to it.
removeAttr
-
name
Removes an attribute from the host object
Parameters:
-
name
StringThe name of the attribute to be removed.
removeQuery
-
url
Removes a query string from the end of the url (if one exists) and returns the result.
Parameters:
-
url
StringURL.
Returns:
Queryless path.
removeRoot
-
url
Removes the root
URL from the front of url (if it's there) and returns
the result. The returned path will always have a leading /
.
Parameters:
-
url
StringURL.
Returns:
Rootless path.
render
()
chainable
Renders this application by appending the viewContainer
node to the
container
node if it isn't already a child of the container, and the
activeView
will be appended the view container, if it isn't already.
You should call this method at least once, usually after the initialization of your app instance so the proper DOM structure is setup and optionally append the container to the DOM if it's not there already.
You may override this method to customize the app's rendering, but you
should expect that the viewContainer
's contents will be modified by the
app for the purpose of rendering the activeView
when it changes.
replace
-
[url]
Replaces the current browser history entry with a new one, and dispatches to the first matching route handler, if any.
Behind the scenes, this method uses HTML5 pushState()
in browsers that
support it (or the location hash in older browsers and IE) to change the
URL.
The specified URL must share the same origin (i.e., protocol, host, and port) as the current page, or an error will occur.
Parameters:
-
[url]
String optionalURL to set. This URL needs to be of the same origin as the current URL. This can be a URL relative to the router's
root
attribute. If no URL is specified, the page's current URL will be used.
Example:
// Starting URL: http://example.com/
router.replace('/path/');
// New URL: http://example.com/path/
router.replace('/path?foo=bar');
// New URL: http://example.com/path?foo=bar
router.replace('/');
// New URL: http://example.com/
reset
-
name
Resets the attribute (or all attributes) to its initial value, as long as the attribute is not readOnly, or writeOnce.
Parameters:
-
name
StringOptional. The name of the attribute to reset. If omitted, all attributes are reset.
Returns:
A reference to the host object.
route
-
route
-
callbacks
Adds a route handler for the specified route
.
The route
parameter may be a string or regular expression to represent a
URL path, or a route object. If it's a string (which is most common), it may
contain named parameters: :param
will match any single part of a URL path
(not including /
characters), and *param
will match any number of parts
of a URL path (including /
characters). These named parameters will be
made available as keys on the req.params
object that's passed to route
handlers.
If the route
parameter is a regex, all pattern matches will be made
available as numbered keys on req.params
, starting with 0
for the full
match, then 1
for the first subpattern match, and so on.
Alternatively, an object can be provided to represent the route and it may
contain a path
property which is a string or regular expression which
causes the route to be process as described above. If the route object
already contains a regex
or regexp
property, the route will be
considered fully-processed and will be associated with any callacks
specified on the object and those specified as parameters to this method.
Note: Any additional data contained on the route object will be
preserved.
Here's a set of sample routes along with URL paths that they match:
-
Route:
/photos/:tag/:page
- URL:
/photos/kittens/1
, params:{tag: 'kittens', page: '1'}
- URL:
/photos/puppies/2
, params:{tag: 'puppies', page: '2'}
- URL:
-
Route:
/file/*path
- URL:
/file/foo/bar/baz.txt
, params:{path: 'foo/bar/baz.txt'}
- URL:
/file/foo
, params:{path: 'foo'}
- URL:
Middleware: Routes also support an arbitrary number of callback
functions. This allows you to easily reuse parts of your route-handling code
with different route. This method is liberal in how it processes the
specified callbacks
, you can specify them as separate arguments, or as
arrays, or both.
If multiple route match a given URL, they will be executed in the order they were added. The first route that was added will be the first to be executed.
Passing Control: Invoking the next()
function within a route callback
will pass control to the next callback function (if any) or route handler
(if any). If a value is passed to next()
, it's assumed to be an error,
therefore stopping the dispatch chain, unless that value is: "route"
,
which is special case and dispatching will skip to the next route handler.
This allows middleware to skip any remaining middleware for a particular
route.
Parameters:
-
route
String | RegExp | ObjectRoute to match. May be a string or a regular expression, or a route object.
-
callbacks
Array | Function | String multipleCallback functions to call whenever this route is triggered. These can be specified as separate arguments, or in arrays, or both. If a callback is specified as a string, the named function will be called on this router instance.
-
req
ObjectRequest object containing information about the request. It contains the following properties.
-
params
Array | ObjectCaptured parameters matched by the route path specification. If a string path was used and contained named parameters, then this will be a key/value hash mapping parameter names to their matched values. If a regex path was used, this will be an array of subpattern matches starting at index 0 for the full match, then 1 for the first subpattern match, and so on. -
path
StringThe current URL path. -
pendingCallbacks
NumberNumber of remaining callbacks the route handler has after this one in the dispatch chain. -
pendingRoutes
NumberNumber of matching routes after this one in the dispatch chain. -
query
ObjectQuery hash representing the URL query string, if any. Parameter names are keys, and are mapped to parameter values. -
route
ObjectReference to the current route object whose callbacks are being dispatched. -
router
ObjectReference to this router instance. -
src
StringWhat initiated the dispatch. In an HTML5 browser, when the back/forward buttons are used, this property will have a value of "popstate". When thedispath()
method is called, thesrc
will be"dispatch"
. -
url
StringThe full URL.
-
-
res
ObjectResponse object containing methods and information that relate to responding to a request. It contains the following properties.
-
req
ObjectReference to the request object.
-
-
next
FunctionFunction to pass control to the next callback or the next matching route if no more callbacks (middleware) exist for the current route handler. If you don't call this function, then no further callbacks or route handlers will be executed, even if there are more that match. If you do call this function, then the next callback (if any) or matching route handler (if any) will be called. All of these functions will receive the same
req
andres
objects that were passed to this route (so you can use these objects to pass data along to subsequent callbacks and routes).-
[err]
String optionalOptional error which will stop the dispatch chaining for thisreq
, unless the value is"route"
, which is special cased to jump skip past any callbacks for the current route and pass control the next route handler.
-
-
Example:
router.route('/photos/:tag/:page', function (req, res, next) {
Y.log('Current tag: ' + req.params.tag);
Y.log('Current page number: ' + req.params.page);
});
// Using middleware.
router.findUser = function (req, res, next) {
req.user = this.get('users').findById(req.params.user);
next();
};
router.route('/users/:user', 'findUser', function (req, res, next) {
// The findUser
middleware puts the user
object on the req
.
Y.log('Current user:' req.user.get('name'));
});
save
-
[url]
Saves a new browser history entry and dispatches to the first matching route handler, if any.
Behind the scenes, this method uses HTML5 pushState()
in browsers that
support it (or the location hash in older browsers and IE) to change the
URL and create a history entry.
The specified URL must share the same origin (i.e., protocol, host, and port) as the current page, or an error will occur.
Parameters:
-
[url]
String optionalURL to set. This URL needs to be of the same origin as the current URL. This can be a URL relative to the router's
root
attribute. If no URL is specified, the page's current URL will be used.
Example:
// Starting URL: http://example.com/
router.save('/path/');
// New URL: http://example.com/path/
router.save('/path?foo=bar');
// New URL: http://example.com/path?foo=bar
router.save('/');
// New URL: http://example.com/
set
-
name
-
value
-
[opts]
Sets the value of an attribute.
Parameters:
-
name
StringThe name of the attribute. If the current value of the attribute is an Object, dot notation can be used to set the value of a property within the object (e.g.
set("x.y.z", 5)
). -
value
AnyThe value to set the attribute to.
-
[opts]
Object optionalOptional data providing the circumstances for the change.
Returns:
A reference to the host object.
setAttrs
-
attrs
-
[opts]
Sets multiple attribute values.
Parameters:
Returns:
A reference to the host object.
showView
-
view
-
[config]
-
[options]
-
[callback]
Sets which view is active/visible for the application. This will set the
app's activeView
attribute to the specified view
.
The view
will be "attached" to this app, meaning it will be both rendered
into this app's viewContainer
node and all of its events will bubble to
the app. The previous activeView
will be "detached" from this app.
When a string-name is provided for a view which has been registered on this
app's views
object, the referenced metadata will be used and the
activeView
will be set to either a preserved view instance, or a new
instance of the registered view will be created using the specified config
object passed-into this method.
A callback function can be specified as either the third or fourth argument,
and this function will be called after the new view
becomes the
activeView
, is rendered to the viewContainer
, and is ready to use.
Parameters:
-
view
String | ViewThe name of a view defined in the
views
object, or a view instance which should become this app'sactiveView
. -
[config]
Object optionalOptional configuration to use when creating a new view instance. This config object can also be used to update an existing or preserved view's attributes when
options.update
istrue
. -
[options]
Object optionalOptional object containing any of the following properties:
-
[callback]
Function optionalOptional callback function to call after new
activeView
is ready to use, the function will be passed:-
view
ViewA reference to the newactiveView
.
-
-
[prepend=false]
Boolean optionalWhether the
view
should be prepended instead of appended to theviewContainer
. -
[render]
Boolean optionalWhether the
view
should be rendered. Note: If no value is specified, a view instance will only be rendered if it's newly created by this method. -
[update=false]
Boolean optionalWhether an existing view should have its attributes updated by passing the
config
object to itssetAttrs()
method. Note: This option does not have an effect if theview
instance is created as a result of calling this method.
-
-
[callback]
Function optionalOptional callback Function to call after the new
activeView
is ready to use. Note: this will overrideoptions.callback
and it can be specified as either the third or fourth argument. The function will be passed the following:-
view
ViewA reference to the new
activeView
.
-
Example:
var app = new Y.App({
views: {
usersView: {
// Imagine that Y.UsersView
has been defined.
type: Y.UsersView
}
},
users: new Y.ModelList()
});
app.route('/users/', function () {
this.showView('usersView', {users: this.get('users')});
});
app.render();
app.navigate('/uses/'); // => Creates a new Y.UsersView
and shows it.
subscribe
()
deprecated
subscribe to an event
toString
()
String
Default toString implementation. Provides the constructor NAME and the instance guid, if set.
Returns:
String representation for this object
unsubscribe
()
deprecated
detach a listener
unsubscribeAll
-
type
Removes all listeners from the specified event. If the event type is not specified, all listeners from all hosted custom events will be removed.
Parameters:
-
type
StringThe type, or name of the event
Properties
events
Object
Hash of CSS selectors mapped to events to delegate to elements matching those selectors.
CSS selectors are relative to the container
element. Events are attached
to the container, and delegation is used so that subscribers are only
notified of events that occur on elements inside the container that match
the specified selectors. This allows the container's contents to be re-
rendered as needed without losing event subscriptions.
Event handlers can be specified either as functions or as strings that map to function names on this view instance or its prototype.
The this
object in event handlers will refer to this view instance. If
you'd prefer this
to be something else, use Y.bind()
to bind a custom
this
object.
Default: {}
Example:
var view = new Y.View({
events: {
// Call this.toggle()
whenever the element with the id
// "toggle-button" is clicked.
'#toggle-button': {click: 'toggle'},
// Call this.hoverOn()
when the mouse moves over any element
// with the "hoverable" class, and this.hoverOff()
when the
// mouse moves out of any element with the "hoverable" class.
'.hoverable': {
mouseover: 'hoverOn',
mouseout : 'hoverOff'
}
}
});
template
Mixed
Template for this view's contents.
This is a convenience property that has no default behavior of its own.
It's only provided as a convention to allow you to store whatever you
consider to be a template, whether that's an HTML string, a Y.Node
instance, a Mustache template, or anything else your little heart
desires.
How this template gets used is entirely up to you and your custom
render()
method.
Default: ''
views
Object
Hash of view-name to metadata used to declaratively describe an application's views and their relationship with the app and its other views.
The view metadata is composed of Objects keyed to a view-name that can have any or all of the following properties:
-
type
: Function or a string representing the view constructor to use to create view instances. If a string is used, the constructor function is assumed to be on theY
object; e.g."SomeView"
->Y.SomeView
. -
preserve
: Boolean for whether the view instance should be retained. By default, the view instance will be destroyed when it is no longer theactiveView
. Iftrue
the view instance will simply beremoved()
from the DOM when it is no longer active. This is useful when the view is frequently used and may be expensive to re-create. -
parent
: String to another named view in this hash that represents the parent view within the application's view hierarchy; e.g. a"photo"
view could have"album"
has itsparent
view. This parent/child relationship is a useful cue for things like transitions. -
instance
: Used internally to manage the current instance of this named view. This can be used if your view instance is created up-front, or if you would rather manage the View lifecycle, but you probably should just let this be handled for you.
If views
are specified at instantiation time, the metadata in the views
Object here will be used as defaults when creating the instance's views
.
Every Y.App
instance gets its own copy of a views
object so this Object
on the prototype will not be polluted.
Default: {}
Example:
// Imagine that Y.UsersView
and Y.UserView
have been defined.
var app = new Y.App({
views: {
users: {
type : Y.UsersView,
preserve: true
},
user: {
type : Y.UserView,
parent: 'users'
}
}
});
Attributes
activeView
View
readonly
The application's active/visible view.
This attribute is read-only, to set the activeView
use the
showView()
method.
Default: null
Fires event activeViewChange
Fires when the value for the configuration attribute activeView
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
allowFallThrough
Boolean
Whether to set window.location
when calling navigate()
if no routes match the specified URL.
Default: true
Fires event allowFallThroughChange
Fires when the value for the configuration attribute allowFallThrough
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
container
HTMLElement | Node | String
Container node which represents the application's bounding-box, into which this app's content will be rendered.
The container node serves as the host for all DOM events attached by the app. Delegation is used to handle events on children of the container, allowing the container's contents to be re-rendered at any time without losing event subscriptions.
The default container is the <body>
Node, but you can override this in
a subclass, or by passing in a custom container
config value at
instantiation time.
When container
is overridden by a subclass or passed as a config
option at instantiation time, it may be provided as a selector string, a
DOM element, or a Y.Node
instance. During initialization, this app's
create()
method will be called to convert the container into a
Y.Node
instance if it isn't one already and stamp it with the CSS
class: "yui3-app"
.
The container is not added to the page automatically. This allows you to have full control over how and when your app is actually rendered to the page.
Default: Y.one('body')
Fires event containerChange
Fires when the value for the configuration attribute container
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
destroyed
Boolean
readonly
Flag indicating whether or not this object has been through the destroy lifecycle phase.
Default: false
Fires event destroyedChange
Fires when the value for the configuration attribute destroyed
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
html5
Boolean
Whether or not this browser is capable of using HTML5 history.
This value is dependent on the value of serverRouting
and will default
accordingly.
Setting this to false
will force the use of hash-based history even on
HTML5 browsers, but please don't do this unless you understand the
consequences.
Fires event html5Change
Fires when the value for the configuration attribute html5
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
initialized
Boolean
readonly
Flag indicating whether or not this object has been through the init lifecycle phase.
Default: false
Fires event initializedChange
Fires when the value for the configuration attribute initialized
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
linkSelector
String | Function
CSS selector string used to filter link click events so that only the links which match it will have the enhanced-navigation behavior of pjax applied.
When a link is clicked and that link matches this selector, navigating
to the link's href
URL using the enhanced, pjax, behavior will be
attempted; and the browser's default way to navigate to new pages will
be the fallback.
By default this selector will match all links on the page.
Default: "a"
Fires event linkSelectorChange
Fires when the value for the configuration attribute linkSelector
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
params
Object
Map of params handlers in the form: name
-> RegExp | Function.
If a param handler regex or function returns a value of false
, null
,
undefined
, or NaN
, the current route will not match and be skipped.
All other return values will be used in place of the original param
value parsed from the URL.
This attribute is intended to be used to set params at init time, or to
completely reset all params after init. To add params after init without
resetting all existing params, use the param()
method.
Default: `{}`
Fires event paramsChange
Fires when the value for the configuration attribute params
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
root
String
Absolute root path from which all routes should be evaluated.
For example, if your router is running on a page at
http://example.com/myapp/
and you add a route with the path /
, your
route will never execute, because the path will always be preceded by
/myapp
. Setting root
to /myapp
would cause all routes to be
evaluated relative to that root URL, so the /
route would then execute
when the user browses to http://example.com/myapp/
.
Default: `''`
Fires event rootChange
Fires when the value for the configuration attribute root
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
Example:
router.set('root', '/myapp');
router.route('/foo', function () { ... });
Y.log(router.hasRoute('/foo')); // => false
Y.log(router.hasRoute('/myapp/foo')); // => true
// Updates the URL to: "/myapp/foo"
router.save('/foo');
routes
Object[]
Array of route objects.
Each item in the array must be an object with the following properties in order to be processed by the router:
-
path
: String or regex representing the path to match. See the docs for theroute()
method for more details. -
callbacks
: Function or a string representing the name of a function on this router instance that should be called when the route is triggered. An array of functions and/or strings may also be provided. See the docs for theroute()
method for more details.
If a route object contains a regex
or regexp
property, or if its
path
is a regular express, then the route will be considered to be
fully-processed. Any fully-processed routes may contain the following
properties:
-
regex
: The regular expression representing the path to match, this property may also be namedregexp
for greater compatibility. -
keys
: Array of named path parameters used to populatereq.params
objects when dispatching to route handlers.
Any additional data contained on these route objects will be retained.
This is useful to store extra metadata about a route; e.g., a name
to
give routes logical names.
This attribute is intended to be used to set routes at init time, or to
completely reset all routes after init. To add routes after init without
resetting all existing routes, use the route()
method.
Default: `[]`
Fires event routesChange
Fires when the value for the configuration attribute routes
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
scrollToTop
Boolean
Whether the page should be scrolled to the top after navigating to a URL.
When the user clicks the browser's back button, the previous scroll position will be maintained.
Default: true
Fires event scrollToTopChange
Fires when the value for the configuration attribute scrollToTop
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
serverRouting
Boolean
Whether or not this application's server is capable of properly routing all requests and rendering the initial state in the HTML responses.
This can have three different values, each having particular implications on how the app will handle routing and navigation:
-
undefined
: The best form of URLs will be chosen based on the capabilities of the browser. Given no information about the server environmentm a balanced approach to routing and navigation is chosen.The server should be capable of handling full-path requests, since full-URLs will be generated by browsers using HTML5 history. If this is a client-side-only app the server could handle full-URL requests by sending a redirect back to the root with a hash-based URL, e.g:
Request: http://example.com/users/1 Redirect to: http://example.com/#/users/1
-
true
: The server is fully capable of properly handling requests to all full-path URLs the app can produce.This is the best option for progressive-enhancement because it will cause all URLs to always have full-paths, which means the server will be able to accurately handle all URLs this app produces. e.g.
http://example.com/users/1
To meet this strict full-URL requirement, browsers which are not capable of using HTML5 history will make requests to the server resulting in full-page reloads.
-
false
: The server is not capable of properly handling requests to all full-path URLs the app can produce, therefore all routing will be handled by this App instance.Be aware that this will cause all URLs to always be hash-based, even in browsers that are capable of using HTML5 history. e.g.
http://example.com/#/users/1
A single-page or client-side-only app where the server sends a "shell" page with JavaScript to the client might have this restriction. If you're setting this to
false
, read the following:
Note: When this is set to false
, the server will never receive
the full URL because browsers do not send the fragment-part to the
server, that is everything after and including the "#".
Consider the following example:
URL shown in browser: http://example.com/#/users/1
URL sent to server: http://example.com/
You should feel bad about hurting our precious web if you forcefully set
either serverRouting
or html5
to false
, because you're basically
punching the web in the face here with your lossy URLs! Please make sure
you know what you're doing and that you understand the implications.
Ideally you should always prefer full-path URLs (not /#/foo/), and want
full-page reloads when the client's browser is not capable of enhancing
the experience using the HTML5 history APIs. Setting this to true
is
the best option for progressive-enhancement (and graceful-degradation).
Default: undefined
Fires event serverRoutingChange
Fires when the value for the configuration attribute serverRouting
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
viewContainer
HTMLElement | Node | String
The node into which this app's views
will be rendered when they become
the activeView
.
The view container node serves as the container to hold the app's
activeView
. Each time the activeView
is set via showView()
, the
previous view will be removed from this node, and the new active view's
container
node will be appended.
The default view container is a <div>
Node, but you can override this
in a subclass, or by passing in a custom viewContainer
config value at
instantiation time. The viewContainer
may be provided as a selector
string, DOM element, or a Y.Node
instance (having the viewContainer
and the container
be the same node is also supported).
The app's render()
method will stamp the view container with the CSS
class "yui3-app-views"
and append it to the app's container
node if
it isn't already, and any activeView
will be appended to this node if
it isn't already.
Default: Y.Node.create(this.containerTemplate)
Fires event viewContainerChange
Fires when the value for the configuration attribute viewContainer
is
changed. You can listen for the event using the on
method if you
wish to be notified before the attribute's value has changed, or
using the after
method if you wish to be notified after the
attribute's value has changed.
Parameters:
-
e
EventFacadeAn Event Facade object with the following attribute-specific properties added:
Events
destroy
Lifecycle event for the destroy phase, fired prior to destruction. Invoking the preventDefault method on the event object provided to subscribers will prevent destruction from proceeding.
Subscribers to the "after" moment of this event, will be notified after destruction is complete (and as a result cannot prevent destruction).
Event Payload:
-
e
EventFacadeEvent object
init
Lifecycle event for the init phase, fired prior to initialization. Invoking the preventDefault() method on the event object provided to subscribers will prevent initialization from occuring.
Subscribers to the "after" momemt of this event, will be notified after initialization of the object is complete (and therefore cannot prevent initialization).
Event Payload:
-
e
EventFacadeEvent object, with a cfg property which refers to the configuration object passed to the constructor.
ready
Fired when the router is ready to begin dispatching to route handlers.
You shouldn't need to wait for this event unless you plan to implement some kind of custom dispatching logic. It's used internally in order to avoid dispatching to an initial route if a browser history change occurs first.
Event Payload:
-
dispatched
Booleantrue
if routes have already been dispatched (most likely due to a history change).