The Widget Package Descriptor

The Widget Package Descriptor (WPD) is a file describing the information of a package, such as its widget classes and external JavaScript files. WPD must be named zk.wpd and placed in the same directory as the widget classes. For example we would place it under web/js/com/foo.

Below is an example zk.wpd of our SimpleLabel.

<package name="com.foo" language="xul/html">
	<widget name="SimpleLabel"/>
</package>

The table below describes the elements used within the above XML and their description.

Name	Description
package	The root element denotes the package name and the language it belongs to
widget	The widget class name (without the package name). If the package contains multiple widgets list them one by one

Having created the configuration the basic implementation of our component is complete. However it will not have any interactive events. Therefore the next logical step is to start adding events to the component.

Package Dependence

It is common for JavaScript packages to depend on another package. For example, zul.grid depends on zul.mesh and zul.menu. This can easily be specified by placing them within the depends attribute as follows.

<package name="zul.grid" language="xul/html" depends="zul.mesh,zul.menu">
	<widget name="Column"/>
	<widget name="Columns"/>
	<widget name="Grid"/>
	<widget name="Row"/>
	<widget name="Rows"/>
	<widget name="Foot"/>
	<widget name="Footer"/>
</package>

Including additonal JavaScript files

If a JavaScript package has to include other JavaScript files, this can be done easily by specifying the file with the script element. For example, the following is the content of zul.db's WPD:

<package name="zul.db" language="xul/html" depends="zk.fmt,zul.inp">
	<script src="datefmt.js"/>
	<widget name="Calendar"/>
	<widget name="Datebox"/>
</package>

For more information, please refer to ZK Client-side Reference: Widget Package Descriptor.