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<!DOCTYPE html>
<html lang='en'><head><meta http-equiv='content-type' content='text/html; charset=UTF-8' /></head><body>
<div class="entry-content">
<div class="entry-title roundTop">
<h1 class="jq-clearfix">.focus()</h1>
<div class="entry-meta jq-clearfix">
Categories:
<span class="category"><a href="http://api.jquery.com/category/events/" title="View all posts in Events">Events</a> > <a href="http://api.jquery.com/category/events/form-events/" title="View all posts in Form Events">Form Events</a></span> | <span class="category"><a href="http://api.jquery.com/category/forms/" title="View all posts in Forms">Forms</a></span>
</div>
</div>
<div id="focus1" class="entry method">
<h2 class="jq-clearfix roundTop section-title">
<span class="name">.focus( handler(eventObject) )</span> <span class="returns">Returns: <a class="return" href="http://api.jquery.com/Types/#jQuery">jQuery</a></span>
</h2>
<div class="jq-box roundBottom entry-details">
<p class="desc"><strong>Description: </strong>Bind an event handler to the "focus" JavaScript event, or trigger that event on an element.</p>
<ul class="signatures">
<li class="signature" id="focus-handlereventObject">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.0/">1.0</a></span>.focus( handler(eventObject) )</h4>
<p class="arguement"><strong>handler(eventObject)</strong>A function to execute each time the event is triggered.</p>
</li>
<li class="signature" id="focus-eventData-handlereventObject">
<h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.4.3/">1.4.3</a></span>.focus( [eventData], handler(eventObject) )</h4>
<p class="arguement"><strong>eventData</strong>A map of data that will be passed to the event handler.</p>
<p class="arguement"><strong>handler(eventObject)</strong>A function to execute each time the event is triggered.</p>
</li>
<li class="signature" id="focus"><h4 class="name">
<span class="versionAdded">version added: <a href="/category/version/1.0/">1.0</a></span>.focus()</h4></li>
</ul>
<div class="longdesc">
<ul>
<li>This method is a shortcut for <code>.bind('focus', handler)</code> in the first and second variations, and <code>.trigger('focus')</code> in the third.</li>
<li>The <code>focus</code> event is sent to an element when it gains focus. This event is implicitly applicable to a limited set of elements, such as form elements (<code><input></code>, <code><select></code>, etc.) and links (<code><a href></code>). In recent browser versions, the event can be extended to include all element types by explicitly setting the element's <code>tabindex</code> property. An element can gain focus via keyboard commands, such as the Tab key, or by mouse clicks on the element.</li>
<li>Elements with focus are usually highlighted in some way by the browser, for example with a dotted line surrounding the element. The focus is used to determine which element is the first to receive keyboard-related events.</li>
</ul>
<p>For example, consider the HTML:</p>
<pre><form>
<input id="target" type="text" value="Field 1" />
<input type="text" value="Field 2" />
</form>
<div id="other">
Trigger the handler
</div>
</pre>
<p>The event handler can be bound to the first input field:</p>
<pre>$('#target').focus(function() {
alert('Handler for .focus() called.');
});</pre>
<p>Now clicking on the first field, or tabbing to it from another field, displays the alert:</p>
<p><span class="output">Handler for .focus() called.</span></p>
<p>We can trigger the event when another element is clicked:</p>
<pre>$('#other').click(function() {
$('#target').focus();
});</pre>
<p>After this code executes, clicks on <span class="output">Trigger the handler</span> will also alert the message.</p>
<p>The <code>focus</code> event does not bubble in Internet Explorer. Therefore, scripts that rely on event delegation with the <code>focus</code> event will not work consistently across browsers. As of version 1.4.2, however, jQuery works around this limitation by mapping <code>focus</code> to the <code>focusin</code> event in its event delegation methods, <a href="http://api.jquery.com/live/"><code>.live()</code></a> and <a href="http://api.jquery.com/delegate/"><code>.delegate()</code></a>.</p>
<blockquote><p>Triggering the focus on hidden elements causes an error in Internet Explorer. Take care to only call <code>.focus()</code> without parameters on elements that are visible.</p></blockquote>
</div>
<h3>Examples:</h3>
<div class="entry-examples" id="entry-examples">
<div id="example-0">
<h4>Example: <span class="desc">Fire focus.</span>
</h4>
<pre class="prettyprint"><code class="example demo-code"><!DOCTYPE html>
<html>
<head>
<style>span {display:none;}</style>
<script src="http://code.jquery.com/jquery-1.7rc2.js"></script>
</head>
<body>
<p><input type="text" /> <span>focus fire</span></p>
<p><input type="password" /> <span>focus fire</span></p>
<script>
$("input").focus(function () {
$(this).next("span").css('display','inline').fadeOut(1000);
});
</script>
</body>
</html></code></pre>
<h4>Demo:</h4>
<div class="demo code-demo"></div>
</div>
<div id="example-1">
<h4>Example: <span class="desc">To stop people from writing in text input boxes, try:</span>
</h4>
<pre class="prettyprint"><code class="example">$("input[type=text]").focus(function(){
$(this).blur();
});</code></pre>
</div>
<div id="example-2">
<h4>Example: <span class="desc">To focus on a login input box with id 'login' on page startup, try:</span>
</h4>
<pre class="prettyprint"><code class="example">$(document).ready(function(){
$("#login").focus();
});</code></pre>
</div>
</div>
</div>
</div>
</div>
</body></html>
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