Views

As mentioned earlier, the Plugins.get( type, filter ) call can return a filtered set of plugins of a given type. Sometimes, however, these plugins are evaluated and organized into a more complicated structure that allows for easier and quicker access. This is where the View comes into play. The View will watch the Plugin mechanisms for Plugins that are added and removed, and mark its view as dirty when appropriate. When the View is nexted ask for its value, it can either recalculate the value or return a cached one.

For a plugin point to use a Factory, it should use the createView( type, options, throwError = false ) method to obtain and/or create it.

const view = Plugins.createView( 'myProject.MyLookupType', options )

The first argument identifies the plugin point type that the View is using , the second object is the options used to configure the factory:

Option Field	Default	Description
name	default	The name of the View. This is used to cache the View so it can be returned from a repeated createFactory() or getFactory() call.
sort	defaultSort	This defines the sort function used to sort the plugins. By default, the sort function uses a string sorting mechanism on the 'sort' key, but alternates functions can be used. If this is 'byNumber', a sort using a number will be installed.
filter	null	The filter used to prune plugins from the View. If processor is supplied, this is not used.
processor	null	A function that, if supplied, this is invoked with an Array of sorted plugins. The result of this function is returned from View.get(). If this is not supplied, the filter options will be used.

If a processor is not supplied, view.get() will return an array of plugins, sorted and filtered according to those options. If the processor is given, the result from the processor defines the shape of the return value of view.get().

When a Plugin of the View's type is added or removed, the view is marked as dirty and is recalculated vi processor or filter on the next invokation of view.get().