1 /* 2 * Copyright (c) 2000 World Wide Web Consortium, 3 * (Massachusetts Institute of Technology, Institut National de 4 * Recherche en Informatique et en Automatique, Keio University). All 5 * Rights Reserved. This program is distributed under the W3C's Software 6 * Intellectual Property License. This program is distributed in the 7 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even 8 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 9 * PURPOSE. 10 * See W3C License http://www.w3.org/Consortium/Legal/ for more details. 11 */ 12 13 package org.w3c.dom.events; 14 15 /** 16 * The <code>Event</code> interface is used to provide contextual information 17 * about an event to the handler processing the event. An object which 18 * implements the <code>Event</code> interface is generally passed as the 19 * first parameter to an event handler. More specific context information is 20 * passed to event handlers by deriving additional interfaces from 21 * <code>Event</code> which contain information directly relating to the 22 * type of event they accompany. These derived interfaces are also 23 * implemented by the object passed to the event listener. 24 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Events-20001113'>Document Object Model (DOM) Level 2 Events Specification</a>. 25 * @since DOM Level 2 26 */ 27 public interface Event { 28 // PhaseType 29 /** 30 * The current event phase is the capturing phase. 31 */ 32 public static final short CAPTURING_PHASE = 1; 33 /** 34 * The event is currently being evaluated at the target 35 * <code>EventTarget</code>. 36 */ 37 public static final short AT_TARGET = 2; 38 /** 39 * The current event phase is the bubbling phase. 40 */ 41 public static final short BUBBLING_PHASE = 3; 42 43 /** 44 * The name of the event (case-insensitive). The name must be an XML name. 45 */ 46 public String getType(); 47 48 /** 49 * Used to indicate the <code>EventTarget</code> to which the event was 50 * originally dispatched. 51 */ 52 public EventTarget getTarget(); 53 54 /** 55 * Used to indicate the <code>EventTarget</code> whose 56 * <code>EventListeners</code> are currently being processed. This is 57 * particularly useful during capturing and bubbling. 58 */ 59 public EventTarget getCurrentTarget(); 60 61 /** 62 * Used to indicate which phase of event flow is currently being 63 * evaluated. 64 */ 65 public short getEventPhase(); 66 67 /** 68 * Used to indicate whether or not an event is a bubbling event. If the 69 * event can bubble the value is true, else the value is false. 70 */ 71 public boolean getBubbles(); 72 73 /** 74 * Used to indicate whether or not an event can have its default action 75 * prevented. If the default action can be prevented the value is true, 76 * else the value is false. 77 */ 78 public boolean getCancelable(); 79 80 /** 81 * Used to specify the time (in milliseconds relative to the epoch) at 82 * which the event was created. Due to the fact that some systems may 83 * not provide this information the value of <code>timeStamp</code> may 84 * be not available for all events. When not available, a value of 0 85 * will be returned. Examples of epoch time are the time of the system 86 * start or 0:0:0 UTC 1st January 1970. 87 */ 88 public long getTimeStamp(); 89 90 /** 91 * The <code>stopPropagation</code> method is used prevent further 92 * propagation of an event during event flow. If this method is called 93 * by any <code>EventListener</code> the event will cease propagating 94 * through the tree. The event will complete dispatch to all listeners 95 * on the current <code>EventTarget</code> before event flow stops. This 96 * method may be used during any stage of event flow. 97 */ 98 public void stopPropagation(); 99 100 /** 101 * If an event is cancelable, the <code>preventDefault</code> method is 102 * used to signify that the event is to be canceled, meaning any default 103 * action normally taken by the implementation as a result of the event 104 * will not occur. If, during any stage of event flow, the 105 * <code>preventDefault</code> method is called the event is canceled. 106 * Any default action associated with the event will not occur. Calling 107 * this method for a non-cancelable event has no effect. Once 108 * <code>preventDefault</code> has been called it will remain in effect 109 * throughout the remainder of the event's propagation. This method may 110 * be used during any stage of event flow. 111 */ 112 public void preventDefault(); 113 114 /** 115 * The <code>initEvent</code> method is used to initialize the value of an 116 * <code>Event</code> created through the <code>DocumentEvent</code> 117 * interface. This method may only be called before the 118 * <code>Event</code> has been dispatched via the 119 * <code>dispatchEvent</code> method, though it may be called multiple 120 * times during that phase if necessary. If called multiple times the 121 * final invocation takes precedence. If called from a subclass of 122 * <code>Event</code> interface only the values specified in the 123 * <code>initEvent</code> method are modified, all other attributes are 124 * left unchanged. 125 * @param eventTypeArg Specifies the event type. This type may be any 126 * event type currently defined in this specification or a new event 127 * type.. The string must be an XML name. Any new event type must not 128 * begin with any upper, lower, or mixed case version of the string 129 * "DOM". This prefix is reserved for future DOM event sets. It is 130 * also strongly recommended that third parties adding their own 131 * events use their own prefix to avoid confusion and lessen the 132 * probability of conflicts with other new events. 133 * @param canBubbleArg Specifies whether or not the event can bubble. 134 * @param cancelableArg Specifies whether or not the event's default 135 * action can be prevented. 136 */ 137 public void initEvent(String eventTypeArg, 138 boolean canBubbleArg, 139 boolean cancelableArg); 140 141 } 142
