/src/mpv5/ui/beans/ExpandablePanel.java

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

/*
 * ExpandablePanel.java
 *
 * Created on Aug 17, 2010, 4:10:12 PM
 */
package mpv5.ui.beans;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.RenderingHints;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.font.FontRenderContext;
import java.awt.font.LineMetrics;
import java.awt.image.BufferedImage;
import javax.swing.JLabel;
import javax.swing.JPanel;

/**
 *
 * @author andreas.weber
 */
public class ExpandablePanel extends javax.swing.JPanel {

    public ExpandablePanel() {
        this("+", new JPanel());
    }

    public JPanel getContentPane() {
        return contentPanel_;
    }

    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">//GEN-BEGIN:initComponents
    private void initComponents() {

        setName("Form"); // NOI18N
        setLayout(new java.awt.BorderLayout());
    }// </editor-fold>//GEN-END:initComponents
    // Variables declaration - do not modify//GEN-BEGIN:variables
    // End of variables declaration//GEN-END:variables
    private boolean selected;
    private JPanel contentPanel_;
    private HeaderPanel headerPanel_;

    private class HeaderPanel extends JPanel implements MouseListener {

        private String text_;
        private Font font;
        private BufferedImage open, closed;
        final int OFFSET = 30, PAD = 5;

        public HeaderPanel(String text) {
            addMouseListener(this);
            text_ = text;
            font = new Font("sans-serif", Font.PLAIN, 12);
            // setRequestFocusEnabled(true);
            setPreferredSize(new Dimension(200, 20));
            int w = getWidth();
            int h = getHeight();

            /*try {
            open = ImageIO.read(new File("images/arrow_down_mini.png"));
            closed = ImageIO.read(new File("images/arrow_right_mini.png"));
            } catch (IOException e) {
            e.printStackTrace();
            }*/

        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2 = (Graphics2D) g;
            g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                    RenderingHints.VALUE_ANTIALIAS_ON);
            int h = getHeight();
            /*if (selected)
            g2.drawImage(open, PAD, 0, h, h, this);
            else
            g2.drawImage(closed, PAD, 0, h, h, this);
             */ // Uncomment once you have your own images
            g2.setFont(font);
            FontRenderContext frc = g2.getFontRenderContext();
            LineMetrics lm = font.getLineMetrics(text_, frc);
            float height = lm.getAscent() + lm.getDescent();
            float x = OFFSET;
            float y = (h + height) / 2 - lm.getDescent();
            g2.drawString(text_, x, y);
        }

        public void mouseClicked(MouseEvent e) {
            toggleSelection();
        }

        public void mouseEntered(MouseEvent e) {
        }

        public void mouseExited(MouseEvent e) {
        }

        public void mousePressed(MouseEvent e) {
        }

        public void mouseReleased(MouseEvent e) {
        }
    }

    public ExpandablePanel(String text, JPanel content) {
        super(new GridBagLayout());
        GridBagConstraints gbc = new GridBagConstraints();
        gbc.insets = new Insets(1, 3, 0, 3);
        gbc.weightx = 1.0;
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridwidth = GridBagConstraints.REMAINDER;

        selected = false;
        headerPanel_ = new HeaderPanel(text);

        setBackground(new Color(200, 200, 220));
        contentPanel_ = content;

        add(headerPanel_, gbc);
        add(contentPanel_, gbc);
        contentPanel_.setVisible(false);

        JLabel padding = new JLabel();
        gbc.weighty = 1.0;
        add(padding, gbc);

    }

    public void toggleSelection() {
        selected = !selected;

        if (contentPanel_.isShowing()) {
            contentPanel_.setVisible(false);
        } else {
            contentPanel_.setVisible(true);
        }

        validate();
        headerPanel_.repaint();
    }
}