Diva.java Source code

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Here is the source code for Diva.java

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/*
* Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
*   - Redistributions of source code must retain the above copyright
*     notice, this list of conditions and the following disclaimer.
*
*   - Redistributions in binary form must reproduce the above copyright
*     notice, this list of conditions and the following disclaimer in the
*     documentation and/or other materials provided with the distribution.
*
*   - Neither the name of Oracle or the names of its
*     contributors may be used to endorse or promote products derived
*     from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.plaf.LayerUI;

public class Diva {
    public static void main(String[] args) {
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createUI();
            }
        });
    }

    public static void createUI() {
        JFrame f = new JFrame("Diva");

        LayerUI<JPanel> layerUI = new SpotlightLayerUI();
        JPanel panel = createPanel();
        JLayer<JPanel> jlayer = new JLayer<JPanel>(panel, layerUI);

        f.add(jlayer);

        f.setSize(300, 200);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    private static JPanel createPanel() {
        JPanel p = new JPanel();

        ButtonGroup entreeGroup = new ButtonGroup();
        JRadioButton radioButton;
        p.add(radioButton = new JRadioButton("Beef", true));
        entreeGroup.add(radioButton);
        p.add(radioButton = new JRadioButton("Chicken"));
        entreeGroup.add(radioButton);
        p.add(radioButton = new JRadioButton("Vegetable"));
        entreeGroup.add(radioButton);

        p.add(new JCheckBox("Ketchup"));
        p.add(new JCheckBox("Mustard"));
        p.add(new JCheckBox("Pickles"));

        p.add(new JLabel("Special requests:"));
        p.add(new JTextField(20));

        JButton orderButton = new JButton("Place Order");
        p.add(orderButton);

        return p;
    }
}

class SpotlightLayerUI extends LayerUI<JPanel> {
    private boolean mActive;
    private int mX, mY;

    @Override
    public void installUI(JComponent c) {
        super.installUI(c);
        JLayer jlayer = (JLayer) c;
        jlayer.setLayerEventMask(AWTEvent.MOUSE_EVENT_MASK | AWTEvent.MOUSE_MOTION_EVENT_MASK);
    }

    @Override
    public void uninstallUI(JComponent c) {
        JLayer jlayer = (JLayer) c;
        jlayer.setLayerEventMask(0);
        super.uninstallUI(c);
    }

    @Override
    public void paint(Graphics g, JComponent c) {
        Graphics2D g2 = (Graphics2D) g.create();

        // Paint the view.
        super.paint(g2, c);

        if (mActive) {
            // Create a radial gradient, transparent in the middle.
            java.awt.geom.Point2D center = new java.awt.geom.Point2D.Float(mX, mY);
            float radius = 72;
            float[] dist = { 0.0f, 1.0f };
            Color[] colors = { new Color(0.0f, 0.0f, 0.0f, 0.0f), Color.BLACK };
            RadialGradientPaint p = new RadialGradientPaint(center, radius, dist, colors);
            g2.setPaint(p);
            g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, .6f));
            g2.fillRect(0, 0, c.getWidth(), c.getHeight());
        }

        g2.dispose();
    }

    @Override
    protected void processMouseEvent(MouseEvent e, JLayer l) {
        if (e.getID() == MouseEvent.MOUSE_ENTERED)
            mActive = true;
        if (e.getID() == MouseEvent.MOUSE_EXITED)
            mActive = false;
        l.repaint();
    }

    @Override
    protected void processMouseMotionEvent(MouseEvent e, JLayer l) {
        Point p = SwingUtilities.convertPoint(e.getComponent(), e.getPoint(), l);
        mX = p.x;
        mY = p.y;
        l.repaint();
    }
}