# lib/goog/events/browserevent.js

1 | // Copyright 2005 The Closure Library Authors. All Rights Reserved.
2 | //
3 | // Licensed under the Apache License, Version 2.0 (the "License");
4 | // you may not use this file except in compliance with the License.
5 | // You may obtain a copy of the License at
6 | //
7 | // http://www.apache.org/licenses/LICENSE-2.0
8 | //
9 | // Unless required by applicable law or agreed to in writing, software
10 | // distributed under the License is distributed on an "AS-IS" BASIS,
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 | // See the License for the specific language governing permissions and
13 | // limitations under the License.
14 |
15 | /**
16 | * @fileoverview A patched, standardized event object for browser events.
17 | *
18 | * <pre>
19 | * The patched event object contains the following members:
20 | * - type {string} Event type, e.g. 'click'
21 | * - target {Object} The element that actually triggered the event
22 | * - currentTarget {Object} The element the listener is attached to
23 | * - relatedTarget {Object} For mouseover and mouseout, the previous object
24 | * - offsetX {number} X-coordinate relative to target
25 | * - offsetY {number} Y-coordinate relative to target
26 | * - clientX {number} X-coordinate relative to viewport
27 | * - clientY {number} Y-coordinate relative to viewport
28 | * - screenX {number} X-coordinate relative to the edge of the screen
29 | * - screenY {number} Y-coordinate relative to the edge of the screen
30 | * - button {number} Mouse button. Use isButton() to test.
31 | * - keyCode {number} Key-code
32 | * - ctrlKey {boolean} Was ctrl key depressed
33 | * - altKey {boolean} Was alt key depressed
34 | * - shiftKey {boolean} Was shift key depressed
35 | * - metaKey {boolean} Was meta key depressed
36 | * - defaultPrevented {boolean} Whether the default action has been prevented
37 | * - state {Object} History state object
38 | *
39 | * NOTE: The keyCode member contains the raw browser keyCode. For normalized
40 | * key and character code use {@link goog.events.KeyHandler}.
41 | * </pre>
42 | *
43 | * @author arv@google.com (Erik Arvidsson)
44 | */
45 |
46 | goog.provide('goog.events.BrowserEvent');
47 | goog.provide('goog.events.BrowserEvent.MouseButton');
48 |
49 | goog.require('goog.events.BrowserFeature');
50 | goog.require('goog.events.Event');
51 | goog.require('goog.events.EventType');
52 | goog.require('goog.reflect');
53 | goog.require('goog.userAgent');
54 |
55 |
56 |
57 | /**
58 | * Accepts a browser event object and creates a patched, cross browser event
59 | * object.
60 | * The content of this object will not be initialized if no event object is
61 | * provided. If this is the case, init() needs to be invoked separately.
62 | * @param {Event=} opt_e Browser event object.
63 | * @param {EventTarget=} opt_currentTarget Current target for event.
64 | * @constructor
65 | * @extends {goog.events.Event}
66 | */
67 | goog.events.BrowserEvent = function(opt_e, opt_currentTarget) {
68 | goog.events.BrowserEvent.base(this, 'constructor', opt_e ? opt_e.type : '');
69 |
70 | /**
71 | * Target that fired the event.
72 | * @override
73 | * @type {Node}
74 | */
75 | this.target = null;
76 |
77 | /**
78 | * Node that had the listener attached.
79 | * @override
80 | * @type {Node|undefined}
81 | */
82 | this.currentTarget = null;
83 |
84 | /**
85 | * For mouseover and mouseout events, the related object for the event.
86 | * @type {Node}
87 | */
88 | this.relatedTarget = null;
89 |
90 | /**
91 | * X-coordinate relative to target.
92 | * @type {number}
93 | */
94 | this.offsetX = 0;
95 |
96 | /**
97 | * Y-coordinate relative to target.
98 | * @type {number}
99 | */
100 | this.offsetY = 0;
101 |
102 | /**
103 | * X-coordinate relative to the window.
104 | * @type {number}
105 | */
106 | this.clientX = 0;
107 |
108 | /**
109 | * Y-coordinate relative to the window.
110 | * @type {number}
111 | */
112 | this.clientY = 0;
113 |
114 | /**
115 | * X-coordinate relative to the monitor.
116 | * @type {number}
117 | */
118 | this.screenX = 0;
119 |
120 | /**
121 | * Y-coordinate relative to the monitor.
122 | * @type {number}
123 | */
124 | this.screenY = 0;
125 |
126 | /**
127 | * Which mouse button was pressed.
128 | * @type {number}
129 | */
130 | this.button = 0;
131 |
132 | /**
133 | * Keycode of key press.
134 | * @type {number}
135 | */
136 | this.keyCode = 0;
137 |
138 | /**
139 | * Keycode of key press.
140 | * @type {number}
141 | */
142 | this.charCode = 0;
143 |
144 | /**
145 | * Whether control was pressed at time of event.
146 | * @type {boolean}
147 | */
148 | this.ctrlKey = false;
149 |
150 | /**
151 | * Whether alt was pressed at time of event.
152 | * @type {boolean}
153 | */
154 | this.altKey = false;
155 |
156 | /**
157 | * Whether shift was pressed at time of event.
158 | * @type {boolean}
159 | */
160 | this.shiftKey = false;
161 |
162 | /**
163 | * Whether the meta key was pressed at time of event.
164 | * @type {boolean}
165 | */
166 | this.metaKey = false;
167 |
168 | /**
169 | * History state object, only set for PopState events where it's a copy of the
170 | * state object provided to pushState or replaceState.
171 | * @type {Object}
172 | */
173 | this.state = null;
174 |
175 | /**
176 | * Whether the default platform modifier key was pressed at time of event.
177 | * (This is control for all platforms except Mac, where it's Meta.)
178 | * @type {boolean}
179 | */
180 | this.platformModifierKey = false;
181 |
182 | /**
183 | * The browser event object.
184 | * @private {Event}
185 | */
186 | this.event_ = null;
187 |
188 | if (opt_e) {
189 | this.init(opt_e, opt_currentTarget);
190 | }
191 | };
192 | goog.inherits(goog.events.BrowserEvent, goog.events.Event);
193 |
194 |
195 | /**
196 | * Normalized button constants for the mouse.
197 | * @enum {number}
198 | */
199 | goog.events.BrowserEvent.MouseButton = {
200 | LEFT: 0,
201 | MIDDLE: 1,
202 | RIGHT: 2
203 | };
204 |
205 |
206 | /**
207 | * Static data for mapping mouse buttons.
208 | * @type {!Array<number>}
209 | */
210 | goog.events.BrowserEvent.IEButtonMap = [
211 | 1, // LEFT
212 | 4, // MIDDLE
213 | 2 // RIGHT
214 | ];
215 |
216 |
217 | /**
218 | * Accepts a browser event object and creates a patched, cross browser event
219 | * object.
220 | * @param {Event} e Browser event object.
221 | * @param {EventTarget=} opt_currentTarget Current target for event.
222 | */
223 | goog.events.BrowserEvent.prototype.init = function(e, opt_currentTarget) {
224 | var type = this.type = e.type;
225 |
226 | // TODO(nicksantos): Change this.target to type EventTarget.
227 | this.target = /** @type {Node} */ (e.target) || e.srcElement;
228 |
229 | // TODO(nicksantos): Change this.currentTarget to type EventTarget.
230 | this.currentTarget = /** @type {Node} */ (opt_currentTarget);
231 |
232 | var relatedTarget = /** @type {Node} */ (e.relatedTarget);
233 | if (relatedTarget) {
234 | // There's a bug in FireFox where sometimes, relatedTarget will be a
235 | // chrome element, and accessing any property of it will get a permission
236 | // denied exception. See:
237 | // https://bugzilla.mozilla.org/show_bug.cgi?id=497780
238 | if (goog.userAgent.GECKO) {
239 | if (!goog.reflect.canAccessProperty(relatedTarget, 'nodeName')) {
240 | relatedTarget = null;
241 | }
242 | }
243 | // TODO(arv): Use goog.events.EventType when it has been refactored into its
244 | // own file.
245 | } else if (type == goog.events.EventType.MOUSEOVER) {
246 | relatedTarget = e.fromElement;
247 | } else if (type == goog.events.EventType.MOUSEOUT) {
248 | relatedTarget = e.toElement;
249 | }
250 |
251 | this.relatedTarget = relatedTarget;
252 |
253 | // Webkit emits a lame warning whenever layerX/layerY is accessed.
254 | // http://code.google.com/p/chromium/issues/detail?id=101733
255 | this.offsetX = (goog.userAgent.WEBKIT || e.offsetX !== undefined) ?
256 | e.offsetX : e.layerX;
257 | this.offsetY = (goog.userAgent.WEBKIT || e.offsetY !== undefined) ?
258 | e.offsetY : e.layerY;
259 |
260 | this.clientX = e.clientX !== undefined ? e.clientX : e.pageX;
261 | this.clientY = e.clientY !== undefined ? e.clientY : e.pageY;
262 | this.screenX = e.screenX || 0;
263 | this.screenY = e.screenY || 0;
264 |
265 | this.button = e.button;
266 |
267 | this.keyCode = e.keyCode || 0;
268 | this.charCode = e.charCode || (type == 'keypress' ? e.keyCode : 0);
269 | this.ctrlKey = e.ctrlKey;
270 | this.altKey = e.altKey;
271 | this.shiftKey = e.shiftKey;
272 | this.metaKey = e.metaKey;
273 | this.platformModifierKey = goog.userAgent.MAC ? e.metaKey : e.ctrlKey;
274 | this.state = e.state;
275 | this.event_ = e;
276 | if (e.defaultPrevented) {
277 | this.preventDefault();
278 | }
279 | };
280 |
281 |
282 | /**
283 | * Tests to see which button was pressed during the event. This is really only
284 | * useful in IE and Gecko browsers. And in IE, it's only useful for
285 | * mousedown/mouseup events, because click only fires for the left mouse button.
286 | *
287 | * Safari 2 only reports the left button being clicked, and uses the value '1'
288 | * instead of 0. Opera only reports a mousedown event for the middle button, and
289 | * no mouse events for the right button. Opera has default behavior for left and
290 | * middle click that can only be overridden via a configuration setting.
291 | *
292 | * There's a nice table of this mess at http://www.unixpapa.com/js/mouse.html.
293 | *
294 | * @param {goog.events.BrowserEvent.MouseButton} button The button
295 | * to test for.
296 | * @return {boolean} True if button was pressed.
297 | */
298 | goog.events.BrowserEvent.prototype.isButton = function(button) {
299 | if (!goog.events.BrowserFeature.HAS_W3C_BUTTON) {
300 | if (this.type == 'click') {
301 | return button == goog.events.BrowserEvent.MouseButton.LEFT;
302 | } else {
303 | return !!(this.event_.button &
304 | goog.events.BrowserEvent.IEButtonMap[button]);
305 | }
306 | } else {
307 | return this.event_.button == button;
308 | }
309 | };
310 |
311 |
312 | /**
313 | * Whether this has an "action"-producing mouse button.
314 | *
315 | * By definition, this includes left-click on windows/linux, and left-click
316 | * without the ctrl key on Macs.
317 | *
318 | * @return {boolean} The result.
319 | */
320 | goog.events.BrowserEvent.prototype.isMouseActionButton = function() {
321 | // Webkit does not ctrl+click to be a right-click, so we
322 | // normalize it to behave like Gecko and Opera.
323 | return this.isButton(goog.events.BrowserEvent.MouseButton.LEFT) &&
324 | !(goog.userAgent.WEBKIT && goog.userAgent.MAC && this.ctrlKey);
325 | };
326 |
327 |
328 | /**
329 | * @override
330 | */
331 | goog.events.BrowserEvent.prototype.stopPropagation = function() {
332 | goog.events.BrowserEvent.superClass_.stopPropagation.call(this);
333 | if (this.event_.stopPropagation) {
334 | this.event_.stopPropagation();
335 | } else {
336 | this.event_.cancelBubble = true;
337 | }
338 | };
339 |
340 |
341 | /**
342 | * @override
343 | */
344 | goog.events.BrowserEvent.prototype.preventDefault = function() {
345 | goog.events.BrowserEvent.superClass_.preventDefault.call(this);
346 | var be = this.event_;
347 | if (!be.preventDefault) {
348 | be.returnValue = false;
349 | if (goog.events.BrowserFeature.SET_KEY_CODE_TO_PREVENT_DEFAULT) {
350 | /** @preserveTry */
351 | try {
352 | // Most keys can be prevented using returnValue. Some special keys
353 | // require setting the keyCode to -1 as well:
354 | //
355 | // In IE7:
356 | // F3, F5, F10, F11, Ctrl+P, Crtl+O, Ctrl+F (these are taken from IE6)
357 | //
358 | // In IE8:
359 | // Ctrl+P, Crtl+O, Ctrl+F (F1-F12 cannot be stopped through the event)
360 | //
361 | // We therefore do this for all function keys as well as when Ctrl key
362 | // is pressed.
363 | var VK_F1 = 112;
364 | var VK_F12 = 123;
365 | if (be.ctrlKey || be.keyCode >= VK_F1 && be.keyCode <= VK_F12) {
366 | be.keyCode = -1;
367 | }
368 | } catch (ex) {
369 | // IE throws an 'access denied' exception when trying to change
370 | // keyCode in some situations (e.g. srcElement is input[type=file],
371 | // or srcElement is an anchor tag rewritten by parent's innerHTML).
372 | // Do nothing in this case.
373 | }
374 | }
375 | } else {
376 | be.preventDefault();
377 | }
378 | };
379 |
380 |
381 | /**
382 | * @return {Event} The underlying browser event object.
383 | */
384 | goog.events.BrowserEvent.prototype.getBrowserEvent = function() {
385 | return this.event_;
386 | };
387 |
388 |
389 | /** @override */
390 | goog.events.BrowserEvent.prototype.disposeInternal = function() {
391 | };