+Event passing
+-------------
+
+The primary method of communication between components of the widget
+set -- specifically, between teams and their widgets -- is event
+passing. Widgets subscribe to named events; when something relevant
+happens (such as the reception of a message from metasearch
+middleware), the event is published, along with the relevant data. All
+widgets that susbcribed to the event are then notified, and can take
+appropriate action.
+
+Different kinds of events have different data associated with
+them. This data is passed when the event is published, and so is made
+available to the subscribing code.
+
+The possible events, and their associated data, are described
+[below](#events).
+
+
Defining new types of widget
----------------------------
* You can add functionality to a widget by subscribing it to an
event's queue using `this.team.queue("EVENT").subscribe`. The
argument is a function which is called whenever the event is
- published. The arguments to the event-callback function are
- different for different events.
+ published.
* As with so much JavaScript programming, the value of the special
variable `this` is lost inside the `subscribe` callback function,
* `String team.currentRecordData()`
These are all simple accessor functions that provide the ability to
-read properties of the team.
+read properties of the team. `submitted` is initially false, then
+becomes true when the first search is submitted (manually or
+automatically).
* `Array team.filters()` --
Another accessor function, providing access to the array of
prevailing filters (which narrow the search results by means
of Pazpar2 filters and limits). This is really too complicated
an object for the widgets to be given access to, but it's
- convenient to do it this way. If you must insist on using
+ convenient to do it this way. If you have a reason for using
this, see the `Navi` widget, which is the only place it's used.
* `Bool team.targetFiltered(targetId)` --
and there is probably no reason for you to use it.
* `Hash team.config()` --
- Access to the team's configuration settings. There is almost
- certainly no reason to use this: the settings that haven't
+ Access to the team's configuration settings. There is
+ rarely a need to use this: the settings that haven't
been overridden are accessible via `this.config`.
* `Void team.set_sortOrder(string)`, `Void team.set_perpage(number)` --
- "Setter" functions for the team's sortOrder and perpage
+ "Setter" functions for the team's `sortOrder` and `perpage`
functions. Unlikely to be needed outside of the `Sort` and
`Perpage` widgets.
* `Queue team.queue(eventName)` --
Returns the queue associated with the named event: this can be
- used to subscribe to the event (or more rarely to publish it).
+ used to subscribe to the event (or more rarely to publish
+ it). See [the section on events, below](#events).
* `Void team.newSearch(query, sortOrder, maxrecs, perpage, limit, targets, targetfilter)` --
Starts a new search with the specified parameters. All but the
query may be omitted, in which case the prevailing defaults
- are used.
+ are used. The meanings of the parameters are those of the
+ same-named [configuration
+ settings](mkws-manual.html#configuration-settings) described in
+ the user's manual.
* `Void team.reShow()` --
Using the existing search, re-shows the result records after a
and returns it in a form that can be invoked as a function,
passed a data-set.
-Some of these methods either (A) are really too low-level and should
-not be exposed, or (B) should be widget-level methods. The present
-infelicities reflect the fact that some code that rightly belongs in
-widgets is still in the team. When we finish migrating it, the widget
-API should get simpler.
+Some of these methods are arguably too low-level and should not be
+exposed; others should probably be widget-level methods. The present
+infelicities should be fixed in future releases, but backwards
+compatibility with the present API will be maintained for at least one
+complete major-release cycle.
Events
------
-FIXME: list of events that can be usefully subscribed to.
+The following events are generated by the widget-set code:
+
+resize-wide
+resize-narrow
+authenticated(authName, realm)
+ready
+log(m_teamName, timestamp, s)
+targets(data)
+stat(data)
+firstrecords(hitcount)
+complete(hitcount)
+facets(data)
+pager(data)
+records(data)
+record(data)
+navi -- consult team.filters.
+
- - -
projects / mkws-moved-to-github.git / blobdiff