FloatablePanel.java

/*
 *  Tiled Map Editor, (c) 2004-2006
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  Adam Turk <aturk@biggeruniverse.com>
 *  Bjorn Lindeijer <bjorn@lindeijer.nl>
 */

package tiled.mapeditor.widget;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.event.ActionEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.prefs.Preferences;

import javax.swing.AbstractAction;
import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSplitPane;
import javax.swing.border.EmptyBorder;

import tiled.util.TiledConfiguration;

/**
 * A floatable panel. The panel has a titlebar which displays the panel title
 * plus a small button which can be used to turn the panel into a frame. When
 * the frame is closed the panel is restored.
 *
 * // todo: Prettify the user interface
 *
 * @version $Id$
 */
public class FloatablePanel extends JPanel
{
    /**
	 * 
	 */
	private static final long serialVersionUID = -5919167759758549835L;
	private final JLabel titleLabel;
    private JDialog frame;
    private final JComponent child;
    private final Frame parent;
    private final Preferences prefs;
    private int dividerSize;

    /**
     * Constructs a floatable panel with the given title. When the panel is
     * floated, it is placed in a {@link JDialog} with <code>parent</code> as
     * its parent.
     *
     * @param parent the parent of the child
     * @param child the child component
     * @param title the title of this panel
     * @param preferencesId the unique identifier for this panel
     */
    public FloatablePanel(Frame parent, JComponent child, String title,
                          String preferencesId) {
        this.child = child;
        this.parent = parent;
        titleLabel = new JLabel(title);
        prefs = TiledConfiguration.node("dock/" + preferencesId);

        final JButton floatButton = new JButton("Float");
        floatButton.setAction(new AbstractAction() {
            /**
			 * 
			 */
			private static final long serialVersionUID = -8816527727997693543L;

			public void actionPerformed(ActionEvent e) {
                setFloating(true);
            }
        });

        JPanel topPanel = new HeaderPanel(new BorderLayout());
        topPanel.add(titleLabel, BorderLayout.WEST);
        topPanel.add(floatButton, BorderLayout.EAST);

        // Start in non-floating state
        // todo: Immediately restore floating state when found in preferences
        setLayout(new BorderLayout());
        add(topPanel, BorderLayout.NORTH);
        add(child, BorderLayout.CENTER);
        dividerSize = 0;
        frame = null;
    }

    private void setFloating(boolean floating) {
        final JSplitPane splitPane = (JSplitPane) getParent();

        if (frame != null && !floating) {
            // Store the floating frame position and size
            prefs.putInt("width", frame.getWidth());
            prefs.putInt("height", frame.getHeight());
            prefs.putInt("x", frame.getX());
            prefs.putInt("y", frame.getY());

            // De-float the child
            frame.getContentPane().remove(child);
            frame.dispose();
            frame = null;
            child.setBorder(null);
            add(child, BorderLayout.CENTER);
            setVisible(true);

            // Restore the old divider location
            final int dividerLocation = prefs.getInt("dividerLocation", 0);
            splitPane.setDividerSize(dividerSize);
            splitPane.setDividerLocation(dividerLocation);
        }
        else if (frame == null && floating)
        {
            // Remember the current divider size
            dividerSize = splitPane.getDividerSize();

            // Store the divider location in the preferences
            prefs.putInt("dividerLocation", splitPane.getDividerLocation());

            // Hide this panel and remove our child panel
            setVisible(false);
            remove(child);
            splitPane.setDividerSize(0);

            child.setBorder(new EmptyBorder(5, 5, 5, 5));

            // Float the child
            frame = new JDialog(parent, titleLabel.getText());
            frame.getContentPane().add(child);
            frame.addWindowListener(new WindowAdapter() {
                @Override
				public void windowClosing(WindowEvent e) {
                    setFloating(false);
                }
            });

            // Restore the floating frame position and size
            final int lastFrameWidth = prefs.getInt("width", 0);
            final int lastFrameHeight = prefs.getInt("height", 0);
            final int lastFrameX = prefs.getInt("x", 0);
            final int lastFrameY = prefs.getInt("y", 0);

            if (lastFrameWidth > 0)
            {
                frame.setSize(lastFrameWidth, lastFrameHeight);
                frame.setLocation(lastFrameX, lastFrameY);
            }
            else
            {
                frame.pack();
                frame.setLocationRelativeTo(parent);
            }
            frame.setVisible(true);
        }
    }

    /**
     * Restore the state from the preferences.
     */
    public void restore() {
        final int dividerLocation = prefs.getInt("dividerLocation", 0);
        final boolean floating = prefs.getBoolean("floating", false);

        if (floating) {
            setFloating(true);
        } else if (dividerLocation > 0) {
            final JSplitPane splitPane = (JSplitPane) getParent();
            splitPane.setDividerLocation(dividerLocation);
        }
    }

    /**
     * Save the state to the preferences.
     */
    public void save() {
        prefs.putBoolean("floating", frame != null);

        if (frame != null) {
            prefs.putInt("width", frame.getWidth());
            prefs.putInt("height", frame.getHeight());
            prefs.putInt("x", frame.getX());
            prefs.putInt("y", frame.getY());
        } else {
            final JSplitPane splitPane = (JSplitPane) getParent();
            prefs.putInt("dividerLocation", splitPane.getDividerLocation());
        }
    }

    /**
     * Sets a new title for this panel.
     * @param title the new title
     */
    public void setTitle(String title) {
        titleLabel.setText(title);

        if (frame != null)
        {
            frame.setTitle(title);
        }
    }

    /**
     * The panel that holds the title label and float button.
     */
    private class HeaderPanel extends JPanel
    {
        /**
		 * 
		 */
		private static final long serialVersionUID = -5026843945529334230L;

		public HeaderPanel(BorderLayout borderLayout) {
            super(borderLayout);
            setBorder(BorderFactory.createEmptyBorder(1, 4, 2, 1));
        }

        @Override
		protected void paintComponent(Graphics g) {
            Color backgroundColor = new Color(200, 200, 240);
            g.setColor(backgroundColor);
            ((Graphics2D) g).fill(g.getClip());
            g.setColor(backgroundColor.darker());
            g.drawLine(0, getHeight() - 1, getWidth() - 1, getHeight() - 1);
        }
    }
}