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<concept id="GUID-BBBA5C6C-4E8B-513A-8FA1-C7A04C54C140" xml:lang="en"><title>Clipboard</title><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>Symbian platform supports the concept of cut, copy and paste by providing

a clipboard. An application can copy data to the clipboard and the same data

can then be pasted in by the same application or by any other application. </p>

<p>The clipboard is a resource which is shared by all applications. An application

must, therefore, hold the clipboard for the minimum time possible. </p>

<section><title>Cut, copy and paste</title> <p>The clipboard is encapsulated

by the <codeph>CClipboard</codeph> class. Applications use this class when

they place data on, or retrieve data from the clipboard. </p> <p>It is implemented

as a direct file store. When the data is placed on the clipboard, it is stored

in the clipboard's store as a stream or a network of streams. Every data type

placed on the clipboard is identified by a UID. This allows a pasting application

to identify the required data. </p> <p>It uses a stream dictionary to maintain

UID and stream ID pairs, and always makes the stream dictionary the root stream

of the store. </p> <p>The essential features of the <codeph>CClipboard</codeph> class

are shown in the following diagram: </p> <fig id="GUID-22419444-933C-5431-9717-CD332A17FCF2">

<title>              Clipboard class structure            </title>

<image href="GUID-15591211-58D3-56B6-868F-D34C30ED7A7A_d0e194125_href.png" placement="inline"/>

</fig> <p>Any type of data can be placed on the clipboard. When retrieving

data, applications check the UID in the stream dictionary to determine whether

there is any data relevant to them. The following diagram illustrates a typical

situation: </p> <fig id="GUID-3ABDDCDD-DBC9-5BD5-8448-8249F535FB06">

<title>              Clipboard store            </title>

<image href="GUID-F5B58B20-B85C-5BCD-B1EB-69CCE42DE6BB_d0e194136_href.png" placement="inline"/>

</fig> </section>

</conbody><related-links>

<link href="GUID-8C94EE15-82EA-4A95-9044-C3404F95BD51.dita"><linktext>Using

Clipboard</linktext></link>

<link href="GUID-B683496C-652E-5F48-924E-52D2FF3A78A7.dita"><linktext>Direct file

stores</linktext></link>

<link href="GUID-79F39C97-75E8-5DB1-B976-8FE76E6E60C9.dita"><linktext>Dictionary

stores</linktext></link>

<link href="GUID-AB705D21-87A3-5F32-A4B9-17B7593DD5C3.dita"><linktext>UID manipulation</linktext>

</link>