/* * Copyright (c) 2006 World Wide Web Consortium, * * (Massachusetts Institute of Technology, European Research Consortium for * Informatics and Mathematics, Keio University). All Rights Reserved. This * work is distributed under the W3C(r) Software License [1] in the hope that * it will be useful, but WITHOUT ANY WARRANTY; without even the implied * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231 */ package org.w3c.dom.events; import org.w3c.dom.DOMException; /** * The <code>EventTarget</code> interface is implemented by all the objects * which could be event targets in an implementation which supports the . * The interface allows registration and removal of event listeners, and * dispatch of events to an event target. * <p> When used with , this interface is implemented by all target nodes and * target ancestors, i.e. all DOM <code>Nodes</code> of the tree support * this interface when the implementation conforms to DOM Level 3 Events * and, therefore, this interface can be obtained by using binding-specific * casting methods on an instance of the <code>Node</code> interface. * <p> Invoking <code>addEventListener</code> or * <code>addEventListenerNS</code> repeatedly on the same * <code>EventTarget</code> with the same values for the parameters * <code>namespaceURI</code>, <code>type</code>, <code>listener</code>, and * <code>useCapture</code> has no effect. Doing so does not cause the * <code>EventListener</code> to be called more than once and does not cause * a change in the triggering order. In order to register a listener for a * different event group () the previously registered listener has to be * removed first. * <p>See also the <a href='http://www.w3.org/TR/2006/WD-DOM-Level-3-Events-20060413'> Document Object Model (DOM) Level 3 Events Specification </a>. * @since DOM Level 2 */ public interface EventTarget { /** * This method allows the registration of an event listener in the * default group and, depending on the <code>useCapture</code> * parameter, on the capture phase of the DOM event flow or its target * and bubbling phases. Invoking this method is equivalent to invoking * <code>addEventListenerNS</code> with the same values for the * parameters <code>type</code>, <code>listener</code>, and * <code>useCapture</code>, and the value <code>null</code> for the * parameters <code>namespaceURI</code> and <code>evtGroup</code>. * @param type Specifies the <code>Event.type</code> associated with the * event for which the user is registering. * @param listener The <code>listener</code> parameter takes an object * implemented by the user which implements the * <code>EventListener</code> interface and contains the method to be * called when the event occurs. * @param useCapture If true, <code>useCapture</code> indicates that the * user wishes to add the event listener for the capture phase only, * i.e. this event listener will not be triggered during the target * and bubbling phases. If <code>false</code>, the event listener will * only be triggered during the target and bubbling phases. */ public void addEventListener(String type, EventListener listener, boolean useCapture); /** * This method allows the removal of event listeners from the default * group. Calling <code>removeEventListener</code> with arguments which * do not identify any currently registered <code>EventListener</code> * on the <code>EventTarget</code> has no effect. The * <code>Event.namespaceURI</code> for which the user registered the * event listener is implied and is <code>null</code>. * <p ><b>Note:</b> Event listeners registered for other event groups * than the default group cannot be removed using this method; see * <code>EventTarget.removeEventListenerNS()</code> for that effect. * @param type Specifies the <code>Event.type</code> for which the user * registered the event listener. * @param listener The <code>EventListener</code> to be removed. * @param useCapture Specifies whether the <code>EventListener</code> * being removed was registered for the capture phase or not. If a * listener was registered twice, once for the capture phase and once * for the target and bubbling phases, each must be removed * separately. Removal of an event listener registered for the capture * phase does not affect the same event listener registered for the * target and bubbling phases, and vice versa. */ public void removeEventListener(String type, EventListener listener, boolean useCapture); /** * This method allows the dispatch of events into the implementation's * event model. The event target of the event is the * <code>EventTarget</code> object on which <code>dispatchEvent</code> * is called. * @param evt The event to be dispatched. * @return Indicates whether any of the listeners which handled the * event called <code>Event.preventDefault()</code>. If * <code>Event.preventDefault()</code> was called the returned value * is <code>false</code>, else it is <code>true</code>. * @exception EventException * UNSPECIFIED_EVENT_TYPE_ERR: Raised if the <code>Event.type</code> * was not specified by initializing the event before * <code>dispatchEvent</code> was called. Specification of the * <code>Event.type</code> as <code>null</code> or an empty string * will also trigger this exception. * <br> DISPATCH_REQUEST_ERR: Raised if the <code>Event</code> object is * already being dispatched. * @exception DOMException * NOT_SUPPORTED_ERR: Raised if the <code>Event</code> object has not * been created using <code>DocumentEvent.createEvent()</code>. * <br> INVALID_CHARACTER_ERR: Raised if <code>Event.type</code> is not * an <a href='http://www.w3.org/TR/2004/REC-xml-names11-20040204/#NT-NCName'>NCName</a> as defined in [<a href='http://www.w3.org/TR/2004/REC-xml-names11-20040204/'>XML Namespaces 1.1</a>] * . * @version DOM Level 3 */ public boolean dispatchEvent(Event evt) throws EventException, DOMException; /** * This method allows the registration of an event listener in a * specified group or the default group and, depending on the * <code>useCapture</code> parameter, on the capture phase of the DOM * event flow or its target and bubbling phases. * @param namespaceURI Specifies the <code>Event.namespaceURI</code> * associated with the event for which the user is registering. * @param type Refer to the <code>EventTarget.addEventListener()</code> * method for a description of this parameter. * @param listener Refer to the * <code>EventTarget.addEventListener()</code> method for a * description of this parameter. * @param useCapture Refer to the * <code>EventTarget.addEventListener()</code> method for a * description of this parameter. * @param evtGroup The object that represents the event group to * associate with the <code>EventListener</code> (see also ). Use * <code>null</code> to attach the event listener to the default * group. * @since DOM Level 3 */ public void addEventListenerNS(String namespaceURI, String type, EventListener listener, boolean useCapture, Object evtGroup); /** * This method allows the removal of an event listener, independently of * the associated event group. Calling <code>removeEventListenerNS</code> * with arguments which do not identify any currently registered * <code>EventListener</code> on the <code>EventTarget</code> has no * effect. * @param namespaceURI Specifies the <code>Event.namespaceURI</code> * associated with the event for which the user registered the event * listener. * @param type Refer to the * <code>EventTarget.removeEventListener()</code> method for a * description of this parameter. * @param listener Refer to the * <code>EventTarget.removeEventListener()</code> method for a * description of this parameter. * @param useCapture Refer to the * <code>EventTarget.removeEventListener()</code> method for a * description of this parameter. * @since DOM Level 3 */ public void removeEventListenerNS(String namespaceURI, String type, EventListener listener, boolean useCapture); }