CMSC 202 Computer Science II, Spring 2007, Section 010x

Lecture 15: Inheritance

Thursday 03/29, 2007

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Assigned Reading:   

Slides As Shown:

• Announcements, etc: [slide view] [print view]

• Inheritance : [slide view] [print view]

• GTKmm : [slide view] [print view]

Topics Covered:

• Answered some questions about Project 3.
• Continued discussion on class derivation and inheritance. In particular, we discussed how C++ handles compatibility between derived class objects and base class objects. We derived a ColorCube class from the Cube class which in turn was derived from the Box class (see previous lecture).

  Programs shown:

  • Simple use of ColorCube, showing order of construction, destruction, and use of base class methods.
    cctest.cpp, cctest.txt.

  • Passing a derived object to a function with base class reference parameters.
    cctest2.cpp, cctest2.txt.

  • Passing a derived object to a function with base class value parameters.
    cctest3.cpp, cctest3.txt.

  • Same as cctest3.cpp, but bar3() is compiled separately.
    ccsep4.cpp, cctest4.cpp, cctest4.txt.

  • Checking out how assignment works, or doesn't.
    cctest5.cpp, cctest5.txt.

  • Checking out pointers and dereferencing.
    cctest6.cpp, cctest6.txt.

  • C++ lets you do BAAAAD things with arrays of objects.
    cctest7.cpp, cctest7.txt.

  • Checking out function overloading and inheritance.
    cctest8.cpp, cctest8.txt.

• Looked briefly at a Unix Graphical User Interface (GUI) tool kit called GTKmm. This tool kit is set up so you create customized windows using class derivation. The "real life" inheritance hierarchy is rather complicated. The programs shown won't compile unless you have gtkmm and associated libraries installed. The programs are here, but you are much better off looking at the GTKmm tutorial.