Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.Color;
import java.awt.Cursor;
import java.awt.Graphics;
import java.awt.Polygon;
import java.awt.Rectangle;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;

import javax.swing.JComponent;
import javax.swing.JFrame;

public class Main {
    public static void main(String[] argv) {
        JFrame f = new JFrame();
        f.setSize(400, 300);
        Polygon p = new Polygon();
        p.addPoint(10, 10);
        p.addPoint(100, 300);
        p.addPoint(300, 300);
        p.addPoint(10, 10);

        PolygonButton btn = new PolygonButton(p, "button");
        f.getContentPane().add(btn);
        WindowListener wndCloser = new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        };
        f.addWindowListener(wndCloser);
        f.setVisible(true);
    }
}

class PolygonButton extends JComponent implements MouseListener, MouseMotionListener {
    static public Color ACTIVE_COLOR = Color.red;

    static public Color INACTIVE_COLOR = Color.darkGray;

    protected String text;

    protected Polygon polygon;

    protected Rectangle rectangle;

    protected boolean isActive;

    protected static PolygonButton button;

    public PolygonButton(Polygon p, String text) {
        polygon = p;
        setText(text);

        setOpaque(false);

        addMouseListener(this);
        addMouseMotionListener(this);

        rectangle = new Rectangle(polygon.getBounds()); // Bug alert!
        rectangle.grow(1, 1);

        setBounds(rectangle);
        polygon.translate(-rectangle.x, -rectangle.y);
    }

    public void setText(String t) {
        text = t;
    }

    public String getText() {
        return text;
    }

    public void mouseMoved(MouseEvent e) {
        if (!rectangle.contains(e.getX(), e.getY()) || e.isConsumed()) {
            if (isActive) {
                isActive = false;
                repaint();
            }
            return; // quickly return, if outside our rectangle
        }

        int x = e.getX() - rectangle.x;
        int y = e.getY() - rectangle.y;
        boolean active = polygon.contains(x, y);

        if (isActive != active)
            setState(active);
        if (active)
            e.consume();
    }

    public void mouseDragged(MouseEvent e) {
    }

    protected void setState(boolean active) {
        isActive = active;
        repaint();
        if (active) {
            if (button != null)
                button.setState(false);
            setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
        } else {
            button = null;
            setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
        }
    }

    public void mouseClicked(MouseEvent e) {
    }

    public void mousePressed(MouseEvent e) {
    }

    public void mouseReleased(MouseEvent e) {
    }

    public void mouseExited(MouseEvent e) {
        mouseMoved(e);
    }

    public void mouseEntered(MouseEvent e) {
        mouseMoved(e);
    }

    public void paint(Graphics g) {
        g.setColor(isActive ? ACTIVE_COLOR : INACTIVE_COLOR);
        g.drawPolygon(polygon);
    }

}