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41 lines
1.6 KiB
41 lines
1.6 KiB
14 years ago
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<h2><a name="abstract">Abstract</a></h2>
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<p>
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Abstract classes are used as base classes. You cannot create
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an instance of an abstract class directly - you need to subclass
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it. In the subclass, you need to overload <i>all</i> of the
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class's <a href="#purevirtual">pure virtual</a> methods. These
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are marked as "pure virtual" in these docs, and are also indicated
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by a " = 0" at the end of the method declaration.
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</p>
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<p>
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If your subclass doesn't overload the pure virtual methods in the
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abstract base class, you won't be able to create an instance of it.
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</p>
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<h2><a name="purevirtual">pure virtual</a></h2>
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<p>
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Pure virtual methods are members of an <a href="#abstract">abstract</a>
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class (they're what makes the class abstract in the first place). Pure
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virtual methods are nothing more than place holders - there is no code
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associated with them
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</p>
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<h2><a name="variables">variables</a></h2>
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<p>
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Class variables can be read and written from Python. Global or static
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variables are <i>read only</i>. Variables that are "protected" or.
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"private" in C++ are not implemented.
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</p>
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<h2><a name="slots">slots</a></h2>
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<p>
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When using Qt or KDE in C++, methods involving connections to slots
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take 2 arguments: a QObject 'receiver' and a char* 'slot' name. In Python
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you only need to provide a single value - the name of a Python callable
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method or function which will be connected to a signal. The method or
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function does not need to be in the class where it is reference, and does
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not have to be in a class at all. There are other options - see the
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"Signals and Slots" documentation for more information.
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</p>
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