Images and OO

"Andrew" <andrew@THRWHITE.remove-dii-this>
Wed, 27 Apr 2011 15:29:09 GMT

I am writing a very simple programs which displays a different coloured
target depending on what colour has been selected (using a combo box).

I have an abstract class called Target and three classes called GreenTarget,
RedTarget and YellowTarget which all extend Target.
Each subclass has a method called getColourIndex which returns an integer
relating to the correct coloured target to load in the images array.

To select the colour and return the correct subclass, I have used the
following code.

class Test extends Panel implements ActionListener
        String colour;
        Choice ch = new Choice();
        Target t;
        int colourIndex;
        Button display = new Button("Display");
        Image[] images = new Image[3];

                // Load Images


         public void actionPerformed(ActionEvent evt)
                 colour = ch.getSelectedItem();

                       t = new RedTarget();
                       t = new YellowTarget();
                       t = new GreenTarget();

                 colourIndex = t.getColourIndex();
        public void paint(Graphics g)

How could this code be better? How can I rearrange the code so that I am not
asking for raw data (the image indexes) from the subclasses?
Should I pass the Graphics object in the paint() method to one of the
Also, should the images be loaded in the init() method or should each
subclass load their own image?

I hope someone can help because I am always having this problem.
I have read the MVC pattern but I am finding it hard to understand.

Hope someone can help me

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