File: base/js/Base.js
/**
* The base module provides the Base class, which objects requiring attribute and custom event support can extend.
* The module also provides two ways to reuse code - It augments Base with the Plugin.Host interface which provides
* plugin support and also provides the BaseCore.build method which provides a way to build custom classes using extensions.
*
* @module base
*/
/**
* The base-base submodule provides the Base class without the Plugin support, provided by Plugin.Host,
* and without the extension support provided by BaseCore.build.
*
* @module base
* @submodule base-base
*/
var AttributeCore = Y.AttributeCore,
AttributeExtras = Y.AttributeExtras,
BaseCore = Y.BaseCore,
BaseObservable = Y.BaseObservable;
/**
* <p>
* A base class which objects requiring attributes and custom event support can
* extend. Base also handles the chaining of initializer and destructor methods across
* the hierarchy as part of object construction and destruction. Additionally, attributes configured
* through the static <a href="#property_ATTRS">ATTRS</a> property for each class
* in the hierarchy will be initialized by Base.
* </p>
*
* <p>
* **NOTE:** Prior to version 3.11.0, ATTRS would get added a class at a time. That is,
* Base would loop through each class in the hierarchy, and add the class' ATTRS, and
* then call it's initializer, and move on to the subclass' ATTRS and initializer. As of
* 3.11.0, ATTRS from all classes in the hierarchy are added in one `addAttrs` call before
* any initializers are called. This fixes subtle edge-case issues with subclass ATTRS overriding
* superclass `setter`, `getter` or `valueFn` definitions and being unable to get/set attributes
* defined by the subclass. This order of operation change may impact `setter`, `getter` or `valueFn`
* code which expects a superclass' initializer to have run. This is expected to be rare, but to support
* it, Base supports a `_preAddAttrs()`, method hook (same signature as `addAttrs`). Components can
* implement this method on their prototype for edge cases which do require finer control over
* the order in which attributes are added (see widget-htmlparser).
* </p>
*
* <p>
* The static <a href="#property_NAME">NAME</a> property of each class extending
* from Base will be used as the identifier for the class, and is used by Base to prefix
* all events fired by instances of that class.
* </p>
*
* @class Base
* @constructor
* @uses BaseCore
* @uses BaseObservable
* @uses AttributeCore
* @uses AttributeObservable
* @uses AttributeExtras
* @uses EventTarget
*
* @param {Object} config Object with configuration property name/value pairs. The object can be
* used to provide default values for the objects published attributes.
*
* <p>
* The config object can also contain the following non-attribute properties, providing a convenient
* way to configure events listeners and plugins for the instance, as part of the constructor call:
* </p>
*
* <dl>
* <dt>on</dt>
* <dd>An event name to listener function map, to register event listeners for the "on" moment of the event.
* A constructor convenience property for the <a href="Base.html#method_on">on</a> method.</dd>
* <dt>after</dt>
* <dd>An event name to listener function map, to register event listeners for the "after" moment of the event.
* A constructor convenience property for the <a href="Base.html#method_after">after</a> method.</dd>
* <dt>bubbleTargets</dt>
* <dd>An object, or array of objects, to register as bubble targets for bubbled events fired by this instance.
* A constructor convenience property for the <a href="EventTarget.html#method_addTarget">addTarget</a> method.</dd>
* <dt>plugins</dt>
* <dd>A plugin, or array of plugins to be plugged into the instance (see PluginHost's plug method for signature details).
* A constructor convenience property for the <a href="Plugin.Host.html#method_plug">plug</a> method.</dd>
* </dl>
*/
function Base() {
BaseCore.apply(this, arguments);
BaseObservable.apply(this, arguments);
AttributeExtras.apply(this, arguments);
}
/**
* The list of properties which can be configured for
* each attribute (e.g. setter, getter, writeOnce, readOnly etc.)
*
* @property _ATTR_CFG
* @type Array
* @static
* @private
*/
Base._ATTR_CFG = BaseCore._ATTR_CFG.concat(BaseObservable._ATTR_CFG);
/**
* The array of non-attribute configuration properties supported by this class.
*
* `Base` supports "on", "after", "plugins" and "bubbleTargets" properties,
* which are not set up as attributes.
*
* This property is primarily required so that when
* <a href="#property__allowAdHocAttrs">`_allowAdHocAttrs`</a> is enabled by
* a class, non-attribute configurations don't get added as ad-hoc attributes.
*
* @property _NON_ATTRS_CFG
* @type Array
* @static
* @private
*/
Base._NON_ATTRS_CFG = BaseCore._NON_ATTRS_CFG.concat(BaseObservable._NON_ATTRS_CFG);
/**
* <p>
* The string to be used to identify instances of
* this class, for example in prefixing events.
* </p>
* <p>
* Classes extending Base, should define their own
* static NAME property, which should be camelCase by
* convention (e.g. MyClass.NAME = "myClass";).
* </p>
* @property NAME
* @type String
* @static
*/
Base.NAME = 'base';
/**
* The default set of attributes which will be available for instances of this class, and
* their configuration. In addition to the configuration properties listed by
* Attribute's <a href="Attribute.html#method_addAttr">addAttr</a> method, the attribute
* can also be configured with a "cloneDefaultValue" property, which defines how the statically
* defined value field should be protected ("shallow", "deep" and false are supported values).
*
* By default if the value is an object literal or an array it will be "shallow" cloned, to
* protect the default value.
*
* @property ATTRS
* @type Object
* @static
*/
Base.ATTRS = AttributeCore.protectAttrs(BaseCore.ATTRS);
/**
Provides a way to safely modify a `Y.Base` subclass' static `ATTRS` after
the class has been defined or created.
Base-based classes cache information about the class hierarchy in order to
efficiently create instances. This cache includes includes the aggregated
`ATTRS` configs. If the static `ATTRS` configs need to be modified after the
class has been defined or create, then use this method which will make sure
to clear any cached data before making any modifications.
@method modifyAttrs
@param {Function} [ctor] The constructor function whose `ATTRS` should be
modified. If a `ctor` function is not specified, then `this` is assumed
to be the constructor which hosts the `ATTRS`.
@param {Object} configs The collection of `ATTRS` configs to mix with the
existing attribute configurations.
@static
@since 3.10.0
**/
Base.modifyAttrs = BaseCore.modifyAttrs;
Y.mix(Base, BaseCore, false, null, 1);
Y.mix(Base, AttributeExtras, false, null, 1);
// Needs to be `true`, to overwrite methods from `BaseCore`.
Y.mix(Base, BaseObservable, true, null, 1);
// Fix constructor
Base.prototype.constructor = Base;
Y.Base = Base;