1 | // |
2 | // EventTarget.h |
3 | // |
4 | // Library: XML |
5 | // Package: DOM |
6 | // Module: DOMEvents |
7 | // |
8 | // Definition of the DOM EventTarget interface. |
9 | // |
10 | // Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH. |
11 | // and Contributors. |
12 | // |
13 | // SPDX-License-Identifier: BSL-1.0 |
14 | // |
15 | |
16 | |
17 | #ifndef DOM_EventTarget_INCLUDED |
18 | #define DOM_EventTarget_INCLUDED |
19 | |
20 | |
21 | #include "Poco/XML/XML.h" |
22 | #include "Poco/DOM/DOMObject.h" |
23 | #include "Poco/XML/XMLString.h" |
24 | |
25 | |
26 | namespace Poco { |
27 | namespace XML { |
28 | |
29 | |
30 | class EventListener; |
31 | class Event; |
32 | |
33 | |
34 | class XML_API EventTarget: public DOMObject |
35 | /// The EventTarget interface is implemented by all Nodes in an implementation |
36 | /// which supports the DOM Event Model. Therefore, this interface can be obtained |
37 | /// by using binding-specific casting methods on an instance of the Node interface. |
38 | /// The interface allows registration and removal of EventListeners on an EventTarget |
39 | /// and dispatch of events to that EventTarget. |
40 | { |
41 | public: |
42 | virtual void addEventListener(const XMLString& type, EventListener* listener, bool useCapture) = 0; |
43 | /// This method allows the registration of event listeners on |
44 | /// the event target. If an EventListener is added to an |
45 | /// EventTarget while it is processing an event, it will not |
46 | /// be triggered by the current actions but may be triggered |
47 | /// during a later stage of event flow, such as the bubbling phase. |
48 | /// If multiple identical EventListeners are registered on the same |
49 | /// EventTarget with the same parameters the duplicate instances are |
50 | /// discarded. They do not cause the EventListener to be called twice and since they are |
51 | /// discarded they do not need to be removed with the removeEventListener method. |
52 | |
53 | virtual void removeEventListener(const XMLString& type, EventListener* listener, bool useCapture) = 0; |
54 | /// This method allows the removal of event listeners from the event |
55 | /// target. If an EventListener is removed from an EventTarget while it is |
56 | /// processing an event, it will not be triggered by the current actions. |
57 | /// EventListeners can never be invoked after being removed. |
58 | /// Calling removeEventListener with arguments which do not identify |
59 | /// any currently registered EventListener on the EventTarget has no effect. |
60 | |
61 | virtual bool dispatchEvent(Event* evt) = 0; |
62 | /// This method allows the dispatch of events into the implementations |
63 | /// event model. Events dispatched in this manner will have the same capturing and |
64 | /// bubbling behavior as events dispatched directly by the |
65 | /// implementation. The target of the event is the EventTarget on |
66 | /// which dispatchEvent is called. |
67 | |
68 | protected: |
69 | virtual ~EventTarget(); |
70 | }; |
71 | |
72 | |
73 | } } // namespace Poco::XML |
74 | |
75 | |
76 | #endif // DOM_EventTarget_INCLUDED |
77 | |