Gadget API

From MemberWiki

Widget Lifecycle Management

A composition canvas will need the ability to:

• Create a widget instance and add it to the composition surface.
  • The first release of the IDE specification is not addressing containment.
  • The jsClass attribute in the widget metadata identifies the name of a javascript prototype function for generating the widget instance.
• Set & Get the values of the published properties of the widget.

Lifecycle Events:

• onLoad: This event signals that the page has finished loading
• onUnload: This event signals that the widget is about to be unloaded (commonly due to a page transition).
• onRemove - This event signals that the a widget instance is being removed from a page. This is different from onUnload in that the canvas is informing the widget instance that it has been removed from the canvas
• onModeChanged: This event signals that the mode for the widget instance has changed. (view, edit and help modes)
• onResize: This event signals that the size for the widget instance has changed.

Gadget Interface

Each instance of a widget is represented using a JavaScript object which provides the communication between the host environment and the native widget executing in a given widget toolkit. The optional jsClass attribute of the widget specifies the name of a JavaScript constructor function to be used when instantiating a given widget.

Below is an interface description of the set and get property calls that are required to be implemented by the widget the syntax below does not denote implementation.

/**
*Generic wrapper classes for widgets
* @constructor
*/
OpenAjax.widgets.WidgetWrapper = function() {};

with (OpenAjax.widgets.WidgetWrapper) {
	/**
	  * Sets the value of the specified property name to the value
	  * @param {String} propertyName This is the name of the property
	  * @param {Object} value The value of the property
	*/
	prototype.setPropertyValue = function(propertyName, value) {};

	/**
	  * Returns the current value of the requested property name.
	  * @param {String} propertyName This is the name of the property to retrieve
	  *
	*/
	prototype.getPropertyValue = function(propertyName) {};


}