author | Dominic Pinkman <Dominic.Pinkman@Nokia.com> |
Tue, 30 Mar 2010 11:56:28 +0100 | |
changeset 5 | f345bda72bc4 |
parent 3 | 46218c8b8afa |
child 14 | 578be2adaf3e |
permissions | -rw-r--r-- |
5
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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<?xml version="1.0" encoding="utf-8"?> |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. --> |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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<!-- This component and the accompanying materials are made available under the terms of the License |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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"Eclipse Public License v1.0" which accompanies this distribution, |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". --> |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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<!-- Initial Contributors: |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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Nokia Corporation - initial contribution. |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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Contributors: |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
parents:
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--> |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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<!DOCTYPE concept |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd"> |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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<concept xml:lang="en" id="GUID-348E8B54-88D9-5D66-AD11-09131EC387F9"><title>Object Orientation Basics</title><prolog><metadata><keywords/></metadata></prolog><conbody><p>Symbian platform C++ uses the standard object-orientated idioms of encapsulation, inheritance, polymorphism and relationships. This page provides a brief summary of these idioms. </p> <section><title>Encapsulation</title> <p>Encapsulation is the art of exposing the aspects of a class that a user can see, but hiding the parts that should not be seen. C++ provides the <codeph>public</codeph> and <codeph>private</codeph> qualifiers to express this: </p> <codeblock id="GUID-078A33E1-511D-53AF-A3EA-E92AF6649153" xml:space="preserve">class TS |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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{ |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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public: |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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S(T1 aArg1, T2 aArg2); |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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void Use(T3 aArg1, T4 aArg2); |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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~S(); |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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private: |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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TInt iInt; |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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TText8 iText; |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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TReal iReal; |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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};</codeblock> <p>Often, functions are public, while data is private. This allows a choice of representations for a class. In practical OO programming, classes often have many private functions. For classes whose representation is a fairly basic property and whose functions would provide direct read/write access to member variables, it is quite acceptable to make data public. </p> </section> <section><title>Inheritance</title> <p>Inheritance is used to express an is-a relationship: for instance, “a button is-a bordered control”. This allows taxonomies of objects to be built up. In C++, inheritance is represented by derivation. </p> <codeblock id="GUID-D8E3EFDD-AF22-5FB1-87EA-4A61BE64A667" xml:space="preserve">class CEikButtonBase : public CEikBorderedControl |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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{ |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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// etc |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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};</codeblock> <p>Encapsulation is enhanced by the <codeph>protected</codeph> qualifier, which means effectively <codeph>private</codeph> for non-derived classes, but <codeph>public</codeph> for derived classes. </p> <p>Inheritance is often over-used by designers of object-oriented systems. Inheritance should not be used unless it is natural: for instance, no-one would dispute that a button is a bordered control. But in Smalltalk, a process is an ordered collection. Of what?! In cases like this, it is better for a class to <i>use</i> another class, rather than <i>derive</i> from it. </p> </section> <section><title>Polymorphism</title> <p>Polymorphism builds on inheritance to allow an <keyword>abstract</keyword> base class to be defined, from which <keyword>concrete</keyword> derived classes may inherit. But, these concrete objects may be used without knowing anything about them, other than that they are derived from the abstract base class. </p> <codeblock id="GUID-87BA8309-C6E7-5389-8A87-2BA8536F1B74" xml:space="preserve">Foo(CCoeControl* aControl) |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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{ |
f345bda72bc4
Week 12 contribution of PDK documentation_content. See release notes for details. Fixes Bug 2054, Bug 1583, Bug 381, Bug 390, Bug 463, Bug 1897, Bug 344, Bug 1319, Bug 394, Bug 1520, Bug 1522, Bug 1892"
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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aControl->Draw(); |
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Addition of the PDK content and example code for Documentation_content according to Feature bug 1607 and bug 1608
Dominic Pinkman <Dominic.Pinkman@Nokia.com>
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}</codeblock> <p>In the code above, for instance, the function knows that a control has a <codeph>Draw()</codeph> function, but it knows nothing about the type of control or how it is drawn. </p> </section> <section><title>Relationships</title> <p>In object oriented systems, the relationships between objects matter very much. Some examples from the Symbian platform include: </p> <ul><li id="GUID-68CCE95A-17AE-5809-B983-B8DE739BDD81"><p>the control environment (<codeph>CCoeEnv</codeph>) has-a window server session (<codeph>RWsSession</codeph>). The lifetime of the window server session is identical to that of the control environment. </p> </li> <li id="GUID-2EB9F004-D6BF-56C9-99F4-652230CE2393"><p>the app UI (<codeph>CEikAppUi</codeph>) uses-a document (<codeph>CEikDocument</codeph>). The document has independent existence: the app UI may come into being for a while, and then be destroyed, but throughout the app UI’s lifetime, it uses the document. </p> </li> </ul> <p>In these relationships, cardinality is important. An app UI uses only one document, and a control environment has only one window server session. But a dialog (<codeph>CEikDialog</codeph>) has any number of lines. </p> </section> </conbody></concept> |