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<concept id="GUID-21DAC50D-7737-42B6-BBDA-E12E8779741B" xml:lang="en"><title>Feedback</title><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>Visual feedback is the most important sensory feedback when entering characters

on screen. Visual feedback can be, for example, button effects, color changes,

status indicators, touch/release state changes, or clearing the screen when

transitioning to next screen.</p>

<p>With audio feedback, lower clicks and tones are preferred over loud beeps,

though most people turn audio feedback off anyway.</p>

<p>Vibration is used as tactile feedback for touch screen interaction or input.

Tactile feedback gives the user an immediate response that the touch event

has been registered.</p>

<p>With the Symbian touch UI, tactile feedback is used in the following situations:</p>

<ul>

<li><p><b>Sensors: </b>a tap on the device by hand provides tactile feedback

to the user in case of a successful interaction.</p></li>

<li><p><b>Touch interaction (touch screen):</b> to indicate to the user that

an interaction event has been successful. For example, when the user presses

a button on the touch screen</p></li>

</ul>

<p><note>Tactile feedback is included in those common UI components where

it has been seen as beneficial. When creating new applications and designing

custom components, tactile feedback is to be included where found useful.

For example, in any button type of UI component, the tactile feedback is naturally

beneficial.</note></p>

<p>In your application, you can use the following feedback types, defined

in <codeph>TTouchLogicalFeedback</codeph>:</p>

<table id="GUID-6FF24F72-C352-4027-AA5D-2D34EBFA00F4">

<tgroup cols="2"><colspec colname="col1"/><colspec colname="col2"/>

<tbody>

<row>

<entry><p><codeph>ETouchFeedbackNone</codeph></p></entry>

<entry><p>Used for disabling feedback in some areas of the application window

while using the area registry.</p></entry>

</row>

<row>

<entry><p><codeph>ETouchFeedbackBasic</codeph></p></entry>

<entry><p>Used as a default feedback for stylus touch down events. For example,

when the mobile device user taps a button or tab.</p></entry>

</row>

<row>

<entry><p><codeph>ETouchFeedbackSensitive</codeph></p></entry>

<entry><p>Provides sensitive feedback in situations when:<ul>

<li><p>the triggering action is not very important (for example, change of

focus in a list).</p></li>

<li><p>there can be a large number of feedback instances within a short time

(for example, text selection which gives feedback on every new selected character).</p></li>

</ul> It is also used for scrolling and dragging.</p></entry>

</row>

</tbody>

</tgroup>

</table>

<p>To use vibration or audio feedback in your application:</p>

<ol>

<li id="GUID-791E80D6-6935-4202-81E0-BA7392A9E1B3"><p>Include <codeph>touchfeedback.lib</codeph> in

your <codeph>.mmp</codeph> file.</p></li>

<li id="GUID-A185188F-F37B-440B-8213-214D77CF3B8B"><p>Include <parmname>touchfeedback.h</parmname>.</p></li>

<li id="GUID-6455F4C1-AEA6-4C30-8E9B-DF9950558E17"><itemgroup><p>To enable

tactile feedback for your application, add the following code.</p><codeblock xml:space="preserve">MTouchFeedback* feedback = MTouchFeedback::Instance();

feedback-&gt;SetFeedbackEnabledForThisApp(ETrue); // enabling feedback is optional  </codeblock><p>Do

not delete the pointer in the controller destructor.</p></itemgroup></li>

<li id="GUID-FC1B810B-99F4-44E5-82DC-46686D6D4198"><itemgroup><p>To use tactile

feedback when a mobile device user points at a control, add the following

code.</p><codeblock xml:space="preserve">void CMyContainerControl::HandlePointerEventL(const TPointerEvent&amp; aPointerEvent)

    {

    // Feedback is always played at pointer down event

    if(aPointerEvent.iType == TPointerEvent::EButton1Down)

        {

        MTouchFeedback* feedback = MTouchFeedback::Instance();  

        if (feedback) 

             { 

             feedback->InstantFeedback(ETouchFeedbackBasic);  

             }  

        }

    // Your other pointer event handling code here

</codeblock></itemgroup></li>

<li id="GUID-A26D8717-1839-4132-98C4-5C09086BB361"><itemgroup><p>To enable

automatic feedback triggering in a specific area of a UI component, add</p><codeblock xml:space="preserve">feedback-&gt;SetFeedbackArea( this, 

                           1, // area Id

                           TRect( 0,0,20,20 ), 

                           ETouchFeedbackBasic, 

                           ETouchEventStylusDown );

</codeblock></itemgroup></li>

</ol>

<note><ul>

<li><p>To use tactile feedback in an application, additional platform security

capabilities are not required.</p></li>

<li><p>Applications themselves do not need to generate feedback effects, unless

they are using custom components. The feedback is generated by components

that the applications use.</p></li>

</ul></note>

<p>For more information, see <xref href="GUID-581A8E4B-12BE-41C0-A20E-3087A80FEECF.dita">Tactile

feedback</xref>.</p>