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                <ol class="chapter"><li class="chapter-item expanded affix "><a href="title-page.html">The Concur UI Framework</a></li><li class="chapter-item expanded affix "><a href="ch00-00-introduction.html">Introduction</a></li><li class="chapter-item expanded "><a href="ch01-00-getting-started.html"><strong aria-hidden="true">1.</strong> Getting Started</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch01-01-installation.html"><strong aria-hidden="true">1.1.</strong> Installation</a></li><li class="chapter-item expanded "><a href="ch01-02-first-concur-program.html"><strong aria-hidden="true">1.2.</strong> Your first Concur program!</a></li></ol></li><li class="chapter-item expanded "><a href="ch02-00-quick-tour.html"><strong aria-hidden="true">2.</strong> A Quick Tour of Concur</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch02-01-anatomy-of-a-widget.html"><strong aria-hidden="true">2.1.</strong> Anatomy of a Widget</a></li><li class="chapter-item expanded "><a href="ch02-02-widget-return-types.html"><strong aria-hidden="true">2.2.</strong> Widget Return Types</a></li><li class="chapter-item expanded "><a href="ch02-03-composing-widgets.html"><strong aria-hidden="true">2.3.</strong> Composing Widgets</a></li><li class="chapter-item expanded "><a href="ch02-04-event-handling.html"><strong aria-hidden="true">2.4.</strong> Event Handling</a></li><li class="chapter-item expanded "><a href="ch02-05-modifying-dom-on-events.html"><strong aria-hidden="true">2.5.</strong> Modifying DOM on Events</a></li><li class="chapter-item expanded "><a href="ch02-06-handling-multiple-events.html" class="active"><strong aria-hidden="true">2.6.</strong> Handling Multiple Events</a></li><li class="chapter-item expanded "><a href="ch02-07-composing-widgets-with-events.html"><strong aria-hidden="true">2.7.</strong> Composing Widgets with Events</a></li><li class="chapter-item expanded "><a href="ch02-08-input-output.html"><strong aria-hidden="true">2.8.</strong> Input Output</a></li></ol></li><li class="chapter-item expanded "><a href="ch03-00-architectural-notes.html"><strong aria-hidden="true">3.</strong> Architectural Notes</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch03-01-replicating-elm-architecture.html"><strong aria-hidden="true">3.1.</strong> Replicating Elm Architecture</a></li><li class="chapter-item expanded "><a href="ch03-02-plan-for-composability-by-breaking-down-components.html"><strong aria-hidden="true">3.2.</strong> Plan for Composability by Breaking Down Components</a></li><li class="chapter-item expanded "><a href="ch03-03-composing-never-ending-widgets.html"><strong aria-hidden="true">3.3.</strong> Composing Never Ending Widgets</a></li></ol></li><li class="chapter-item expanded "><a href="ch04-00-signals.html"><strong aria-hidden="true">4.</strong> Signals</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch04-01-introduction-to-signals.html"><strong aria-hidden="true">4.1.</strong> Introduction</a></li><li class="chapter-item expanded "><a href="ch04-02-your-first-signal.html"><strong aria-hidden="true">4.2.</strong> Your First Signal</a></li><li class="chapter-item expanded "><a href="ch04-03-introduction-to-signals.html"><strong aria-hidden="true">4.3.</strong> Converting Display Widgets</a></li><li class="chapter-item expanded "><a href="ch04-04-signal-composition.html"><strong aria-hidden="true">4.4.</strong> Signal Composition</a></li><li class="chapter-item expanded "><a href="ch04-05-signal-example.html"><strong aria-hidden="true">4.5.</strong> Signal Example</a></li><li class="chapter-item expanded "><a href="ch04-06-some-notes-on-signal-usage.html"><strong aria-hidden="true">4.6.</strong> Some Notes on Signal Usage</a></li></ol></li><li class="chapter-item expanded "><a href="ch05-00-faqs.html"><strong aria-hidden="true">5.</strong> FAQs</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="ch05-01-why-concur.html"><strong aria-hidden="true">5.1.</strong> Why the Concur Model</a></li><li class="chapter-item expanded "><a href="ch05-02-jumping-into-the-middle-of-widgets.html"><strong aria-hidden="true">5.2.</strong> Jumping Into the Middle of Widgets</a></li></ol></li></ol>
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                        <h1><a class="header" href="#handling-multiple-events" id="handling-multiple-events">Handling Multiple Events</a></h1>
<p>You can have mutliple event handlers on the same widget easily.</p>
<p>Here's an example of an input element with both change and focus handlers.</p>
<pre><code class="language-purescript">data Action = Changed String | Focused

inputWidget :: Widget HTML Action
inputWidget = input [(Changed &lt;&lt;&lt; unsafeTargetValue) &lt;$&gt; onChange, Focused &lt;$ onFocus]
</code></pre>
<p>(The <code>unsafeTargetValue</code> is equivalent to <code>event.target.value</code> in Javascript. It's literally defined as <code>(unsafeCoerce e).target.value</code>. It's &quot;unsafe&quot; because it can't statically guarantee that the onChange handler has been called on a target with a value. We are considering implementing a better more-typesafe API for getting the target value.)</p>
<p>Here <code>inputWidget</code> will return an <code>Action</code>, whenever the text is changed, or when it receives focus.</p>
<p>You don't need an action data type if you decide to process the action in line. For example, if you maintain a state -</p>
<pre><code class="language-purescript">type State = {focusCount:: Int, currentText :: String}

inputWidget :: State -&gt; Widget HTML State
inputWidget st = input [st {focusCount = st.focusCount+1} &lt;$ onFocus
                       , ((\s -&gt; st {currentText = s}) &lt;&lt;&lt; unsafeTargetValue) &lt;$&gt; onChange]
</code></pre>
<p>Now <code>inputWidget</code> will return the new application state whenever the text is changed or whenever it receives focus.</p>

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