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58          <dd class="todo">
59            Undocumented.
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61          <dd>
62            Description of this parameter from the json schema.
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64          <dd>
65            This parameter was added in version
66            <b><span></span></b>.
67            You must omit this parameter in earlier versions,
68            and you may omit it in any version.  If you require this
69            parameter, the manifest key
70            <a href="manifest.html#minimum_chrome_version">minimum_chrome_version</a>
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90
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243      <div id="pageTitle">
244        <h1 class="page_title">Events</h1>
245      </div>
246        <!-- TABLE OF CONTENTS -->
247        <div id="toc" style="display: none; ">
248          <h2>Contents</h2>
249          <ol>
250            <li>
251              <a>h2Name</a>
252              <ol>
253                <li>
254                  <a>h3Name</a>
255                </li>
256              </ol>
257            </li>
258              <li>
259                <a href="#apiReference">API reference</a>
260                <ol>
261                  <li>
262                    <a href="#properties">Properties</a>
263                    <ol>
264                      <li>
265                        <a href="#property-anchor">propertyName</a>
266                      </li>
267                    </ol>
268                  </li>
269                  <li>
270                    <a href="#methods">Methods</a>
271                    <ol>
272                      <li>
273                        <a href="#method-anchor">methodName</a>
274                      </li>
275                    </ol>
276                  </li>
277                  <li>
278                    <a href="#events">Events</a>
279                    <ol>
280                      <li>
281                        <a href="#event-anchor">eventName</a>
282                      </li>
283                    </ol>
284                  </li>
285                  <li>
286                    <a href="#types">Types</a>
287                    <ol>
288                      <li>
289                        <a href="#id-anchor">id</a>
290                      </li>
291                    </ol>
292                  </li>
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294              </li>
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304        <!-- STATIC CONTENT PLACEHOLDER -->
305        <div id="static"><p>
306An <code>Event</code> is an object
307that allows you to be notified
308when something interesting happens.
309Here's an example of using the
310<code>chrome.tabs.onCreated</code> event
311to be notified whenever there's a new tab:
312</p>
313
314<pre>chrome.tabs.onCreated.<b>addListener(function(</b>tab<b>) {</b>
315  appendToLog('tabs.onCreated --'
316              + ' window: ' + tab.windowId
317              + ' tab: '    + tab.id
318              + ' index: '  + tab.index
319              + ' url: '    + tab.url);
320<b>});</b>
321</pre>
322
323<p>
324As the example shows,
325you register for notification using <code>addListener()</code>.
326The argument to <code>addListener()</code>
327is always a function that you define to handle the event,
328but the parameters to the function depend on
329which event you're handling.
330Checking the documentation for
331<a href="tabs.html#event-onCreated"><code>chrome.tabs.onCreated</code></a>,
332you can see that the function has a single parameter:
333a <a href="tabs.html#type-Tab">Tab</a> object
334that has details about the newly created tab.
335</p>
336
337<h2>
338Methods
339</h2>
340
341<p>
342You can invoke the following methods on any <code>Event</code> object:
343</p>
344
345<pre>void addListener(function callback(...))
346void removeListener(function callback(...))
347bool hasListener(function callback(...))
348</pre>
349
350<!-- [PENDING: explain removeListener and hasListener] -->
351</div>
352
353        <!-- API PAGE -->
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355        <a name="apiReference"></a>
356        <h2>API reference: chrome.apiname </h2>
357
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360            <a name="properties"></a>
361            <h3 id="properties">Properties</h3>
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368                <span>chrome.extension</span><span>lastError</span>
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385
386              <div class="summary"><span>void</span>
387                  <!-- Note: intentionally longer 80 columns -->
388                  <span>chrome.module.methodName</span>(<span><span>, </span><span></span>
389                      <var><span></span></var></span>)</div>
390
391              <div class="description">
392                <p class="todo">Undocumented.</p>
393                <p>
394                  A description from the json schema def of the function goes here.
395                </p>
396
397                <!-- PARAMETERS -->
398                <h4>Parameters</h4>
399                <dl>
400                  <div>
401                    <div>
402                    </div>
403                  </div>
404                </dl>
405
406                <!-- RETURNS -->
407                <h4>Returns</h4>
408                <dl>
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410                    <div>
411                    </div>
412                  </div>
413                </dl>
414
415                <!-- CALLBACK -->
416                <div>
417                  <div>
418                  <h4>Callback function</h4>
419                  <p>
420                    The callback <em>parameter</em> should specify a function
421                    that looks like this:
422                  </p>
423                  <p>
424                    If you specify the <em>callback</em> parameter, it should
425                    specify a function that looks like this:
426                  </p>
427
428                  <!-- Note: intentionally longer 80 columns -->
429                  <pre>function(<span>Type param1, Type param2</span>) <span class="subdued">{...}</span>;</pre>
430                  <dl>
431                    <div>
432                      <div>
433                      </div>
434                    </div>
435                  </dl>
436                  </div>
437                </div>
438
439                <!-- MIN_VERSION -->
440                <p>
441                  This function was added in version <b><span></span></b>.
442                  If you require this function, the manifest key
443                  <a href="manifest.html#minimum_chrome_version">minimum_chrome_version</a>
444                  can ensure that your extension won't be run in an earlier browser version.
445                </p>
446              </div> <!-- /description -->
447
448            </div>  <!-- /apiItem -->
449
450          </div>  <!-- /apiGroup -->
451
452          <!-- EVENTS -->
453          <div class="apiGroup">
454            <a name="events"></a>
455            <h3 id="events">Events</h3>
456
457            <!-- iterates over all events -->
458            <div class="apiItem">
459              <a></a>
460              <h4>event name</h4>
461
462              <div class="summary">
463                <!-- Note: intentionally longer 80 columns -->
464                <span class="subdued">chrome.bookmarks</span><span>onEvent</span><span class="subdued">.addListener</span>(function(<span>Type param1, Type param2</span>) <span class="subdued">{...}</span>);
465              </div>
466
467              <div class="description">
468                <p class="todo">Undocumented.</p>
469                <p>
470                  A description from the json schema def of the event goes here.
471                </p>
472
473                <!-- PARAMETERS -->
474                <h4>Parameters</h4>
475                <dl>
476                  <div>
477                    <div>
478                    </div>
479                  </div>
480                </dl>
481
482              </div> <!-- /decription -->
483
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485
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487
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492
493            <!-- iterates over all types -->
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495              <a></a>
496              <h4>type name</h4>
497
498              <div>
499              </div>
500
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502
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