org.symbian.wrttools.doc.WRTKit/html/WRTKit_Using_buttons-GUID-8b14cec9-92cc-4bde-83c2-ad0a30a84942.html
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Using buttons</title>
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<h1 class="topictitle1">
Using buttons</h1>
<div>
<p>
You can let users trigger actions by placing a FormButton or
NavigationButton control in a view. Use FormButtons for actions that
start some process and NavigationButton controls for situations
where pressing the button should take the viewer to another view.
</p>
<div class="fignone" id="GUID-8B14CEC9-92CC-4BDE-83C2-AD0A30A84942__GUID-B008BB2B-C5B2-446D-BCED-2824528CF7CC"><a name="GUID-8B14CEC9-92CC-4BDE-83C2-AD0A30A84942__GUID-B008BB2B-C5B2-446D-BCED-2824528CF7CC"><!-- --></a><span class="figcap">Figure 1.
FormButton controls</span>
<br /><img src="FormButton_Controls_Screenshot_1.png" /><br />
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<p>
You can find out when a button has been pressed by registering a
callback function as an event listener to the button. The event type
for button presses is "ActionPerformed". You can use whatever name
you like for the callback function. The function is passed the event
object as an argument. A typical callback function looks like this:
</p>
<pre>
// Callback function for button presses.
function buttonPressed(event) {
// implement what happens when the button is pressed here
}
</pre>
<p>
Creating a button, registering the event listener and adding the
button to a view is demonstrated below. The example creates a
FormButton:
</p>
<pre>
// create button
var button = new FormButton("button1", "Press me!");
button.addEventListener("ActionPerformed", buttonPressed);
exampleView.addControl(button);
</pre>
<p>
Note that the example assumes that a view has already been created
and that the "exampleView" variable refers to that view. "button1"
is a unique identifier for the button that allows it to be identified
for example if several different controls are using a shared event
listener function. The event listener function could examine the event
object and check the identifier of the source control for the event.
</p>
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<div class="parentlink"><strong>Parent topic:</strong> <a href="WRTKit_Common_WRTKit_tasks-GUID-24870895-4449-4307-9a54-7c90f7b3905e.html">Common WRTKit tasks</a></div>
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