<?xml version="1.0" encoding="utf-8"?>+
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<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->+
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<!-- This component and the accompanying materials are made available under the terms of the License +
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"Eclipse Public License v1.0" which accompanies this distribution, +
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and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->+
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<!-- Initial Contributors:+
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    Nokia Corporation - initial contribution.+
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Contributors: +
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-->+
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<!DOCTYPE concept+
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  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">+
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<concept id="GUID-6690CEFF-AE08-4881-AF52-70C097EB2871" xml:lang="en"><title>Unavailable+
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items</title><prolog><metadata><keywords/></metadata></prolog><conbody>+
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<p>Situations often occur where a certain function cannot be used. In these+
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cases, the corresponding items in the Options menu must either be hidden,+
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or there must be an error message given when the user tries to access a function+
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that cannot be accomplished. The Symbian user interface does+
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not use dimming of menu items.</p>+
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<p>This is a trade-off issue: removing unnecessary options makes the Options+
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menus shorter, but at the same time it changes the menu from situation to+
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situation, preventing users from learning the function locations. It may even+
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cause frustration if the users expect some function to be found in the menu,+
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but it is sometimes not there.</p>+
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<ul>+
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<li><p>In case the user has no reason to search for a certain function in+
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the given situation, it should be hidden. As an extreme example, the Delete+
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option is not needed when there are no items to be deleted. </p></li>+
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<li><p>If the user searches for a function, even though it cannot be used+
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in the current situation, it is often better to display the option and give+
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an appropriate message if the user tries to access that function.</p><p><ul>+
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<li><p>An example of this is Digital Rights Management (DRM) protected files:+
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for example, sending commands shall be visible in the user interface although+
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sending such a file would not be allowed. Appropriate DRM-specific notifications+
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are displayed if the user attempts to select one of the options that the user+
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is not allowed to perform on DRM-protected media objects. This is to facilitate+
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end-user's learning of the DRM concept.</p></li>+
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</ul></p></li>+
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</ul>+
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</conbody></concept>+
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