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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>The 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 id="GUID-848D26F4-3875-4BF7-AAEC-476F709B9E6E"><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_d0e176040_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_d0e176051_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>
</related-links></concept>