Panther Painter 

An interactive Java applet

Select a shape, color, and size (such as 200), then press the "Go" button.

(Code by C. Liu; comments by Thomas Albert)

The HTML source for this web page contains an applet:
<applet code="coloredShapes.class" width="500" height="300">
</applet>

Source Code for coloredShapes.java

// colorShapes.java is a Java 1.1 applet that allows the user to specify a
// shape, color, and size for an object that appears on the canvas when
// the user presses the "Go" button.

import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.math.*;

public class coloredShapes extends Applet{
    Button b1;    // For the "Go" button.
    TextField tf;    // For user to specify the size.
    Choice shape,color; 
    Label label1,label2,label3;    // Labels for shape, color, size.

    myCanvas mc;

    class myCanvas extends Canvas{   // Innerclass of coloredShapes. 
        int x;    // Declare the variable for the size.

        public myCanvas()    // Constructor for the canvas that displays the shape.
        {
        }

    public void paint(Graphics g)
    {
        // Get the size the user types in the text field.
        int x=Integer.parseInt(tf.getText()); 
        int[] xcoord={x/2,x,0}; // Radius of circle uses x/2.
        int[] ycoord={0,x,x};
        if((color.getSelectedItem()).equals("Blue"))
        g.setColor(Color.blue);
        if((color.getSelectedItem()).equals("Green"))
        g.setColor(Color.green);
        if((color.getSelectedItem()).equals("Red"))
        g.setColor(Color.red);

        if((shape.getSelectedItem()).equals("Circle"))
        g.fillOval(0, 0, x, x); // Start circle in top left.

        if((shape.getSelectedItem()).equals("Triangle"))
        g.fillPolygon(xcoord,ycoord,3); 

        if((shape.getSelectedItem()).equals("Square"))
        g.fillRect(0, 0, x, x);
    }
}

    public void init(){ // The user interface.
        setLayout(new BorderLayout());
        b1=new Button("Go");
        tf=new TextField("0",7);
        mc=new myCanvas(); 
        shape=new Choice();
        shape.add("Circle");
        shape.add("Triangle");
        shape.add("Square"); 
        color=new Choice();
        color.add("Blue");
        color.add("Green");
        color.add("Red");
        label1=new Label("Shape");
        label2=new Label("Color");
        label3=new Label("Size");
        Panel p=new Panel();
        p.add(label1);
        p.add(shape);
        p.add(label2);
        p.add(color);
        p.add(label3);
        p.add(tf);
        p.add(b1);
        add("Center",mc);
        add("South",p);
        b1.addActionListener(new B());   // Capture the event when user presses the "Go" button.
    }

        class B implements ActionListener{ // Innerclass of coloredShapes. 
            public void actionPerformed(ActionEvent e)
        {
            // When the user presses the "Go" button, repaint.
            mc.repaint(); 
        }
    }
}

Last update: October 21, 2000