path: root/libjava/javax/swing/plaf/basic/BasicDesktopIconUI.java

/* BasicDesktopIconUI.java --
   Copyright (C) 2004, 2005 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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terms of your choice, provided that you also meet, for each linked
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package javax.swing.plaf.basic;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyVetoException;

import javax.swing.Icon;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JDesktopPane;
import javax.swing.JInternalFrame;
import javax.swing.JInternalFrame.JDesktopIcon;
import javax.swing.SwingConstants;
import javax.swing.border.Border;
import javax.swing.event.MouseInputAdapter;
import javax.swing.event.MouseInputListener;
import javax.swing.plaf.ComponentUI;
import javax.swing.plaf.DesktopIconUI;

/**
 * This class acts as the UI delegate for JDesktopIcons for the Basic look and feel.
 */
public class BasicDesktopIconUI extends DesktopIconUI
{
  /**
   * This helper class handles mouse events that occur on the JDesktopIcon.
   */
  public class MouseInputHandler extends MouseInputAdapter
  {
    /** The x offset from the MouseEvent coordinates to the top left corner. */
    private transient int xOffset;

    /** The y offset fromt he MouseEvent coordinates to the top left corner. */
    private transient int yOffset;

    /** A cached value of the JDesktopPane that parents this JDesktopIcon. */
    private transient JDesktopPane pane;

    /**
     * This method is called when the mouse is dragged in the JDesktopIcon.
     *
     * @param e The MouseEvent.
     */
    public void mouseDragged(MouseEvent e)
    {
      Rectangle b = desktopIcon.getBounds();

      moveAndRepaint(desktopIcon, b.x + e.getX() - xOffset,
                     b.y + e.getY() - yOffset, b.width, b.height);
    }

    /**
     * This method is called when the mouse is moved in the JDesktopIcon.
     *
     * @param e The MouseEvent.
     */
    public void mouseMoved(MouseEvent e)
    {
      // Nothing to do.
    }

    /**
     * This method is called when the mouse is pressed in the JDesktopIcon.
     *
     * @param e The MouseEvent.
     */
    public void mousePressed(MouseEvent e)
    {
      xOffset = e.getX();
      yOffset = e.getY();
      pane = frame.getDesktopPane();
      if (pane != null)
	pane.getDesktopManager().beginDraggingFrame(desktopIcon);
    }

    /**
     * This method is called when the mouse is released in the JDesktopIcon.
     *
     * @param e The MouseEvent.
     */
    public void mouseReleased(MouseEvent e)
    {
      if (pane != null)
	pane.getDesktopManager().endDraggingFrame(desktopIcon);
      xOffset = 0;
      yOffset = 0;
    }

    /**
     * This method moves and repaints the JDesktopIcon to the given bounds.
     *
     * @param f The JComponent to move and repaint.
     * @param newX The new x coordinate.
     * @param newY The new y coordinate.
     * @param newWidth The new width.
     * @param newHeight The new height.
     */
    public void moveAndRepaint(JComponent f, int newX, int newY, int newWidth,
                               int newHeight)
    {
      if (pane != null)
	pane.getDesktopManager().dragFrame(f, newX, newY);
      else
	desktopIcon.setBounds(newX, newY, newWidth, newHeight);
    }
  }

  /**
   * This class acts as the border for the JDesktopIcon.
   */
  private class DesktopIconBorder implements Border
  {
    /** The left inset value. */
    int left = 10;

    /** The top inset value. */
    int top = 4;

    /** The right inset value. */
    int right = top;

    /** The bottom inset value. */
    int bottom = top;

    /**
     * This method returns the insets of the border.
     *
     * @param c The Component to find border insets for.
     *
     * @return The border insets.
     */
    public Insets getBorderInsets(Component c)
    {
      return new Insets(top, left, bottom, right);
    }

    /**
     * This method returns whether the border is opaque.
     *
     * @return Whether the border is opaque.
     */
    public boolean isBorderOpaque()
    {
      return true;
    }

    /**
     * This method paints the border.
     *
     * @param c The Component the border is in.
     * @param g The Graphics object to paint with.
     * @param x The x coordinate of the Component.
     * @param y The y coordinate of the Component.
     * @param width The width of the Component.
     * @param height The height of the Component.
     */
    public void paintBorder(Component c, Graphics g, int x, int y, int width,
                            int height)
    {
      g.translate(x, y);
      Color saved = g.getColor();

      g.setColor(Color.LIGHT_GRAY);

      g.fillRect(0, 0, left, height);
      g.fillRect(0, 0, width, top);
      g.fillRect(0, height - bottom, width, bottom);
      g.fillRect(width - right, 0, right, height);

      g.setColor(Color.BLACK);
      g.drawRect(0, 0, width - 1, height - 1);

      int fHeight = height / 4;
      int hLeft = left / 2;

      g.setColor(Color.BLACK);
      g.fillRect(hLeft, fHeight, 2, 2);
      g.fillRect(hLeft, fHeight * 2, 2, 2);
      g.fillRect(hLeft, fHeight * 3, 2, 2);

      g.setColor(saved);
      g.translate(-x, -y);
    }
  }

  /** The static width and height of the iconSize. */
  private static final int iconSize = 16;

  /**
   * This class represents the default frame icon when none
   * is supplied by the JInternalFrame.
   */
  static class InternalFrameDefaultMenuIcon implements Icon
  {
    /**
     * This returns the icon height.
     *
     * @return The icon height.
     */
    public int getIconHeight()
    {
      return iconSize;
    }

    /**
     * This returns the icon width.
     *
     * @return The icon width.
     */
    public int getIconWidth()
    {
      return iconSize;
    }

    /**
     * This method paints the icon.
     *
     * @param c The Component this icon belongs to.
     * @param g The Graphics object to paint with.
     * @param x The x coordinate to paint at.
     * @param y The y coordinate to paint at.
     */
    public void paintIcon(Component c, Graphics g, int x, int y)
    {
      g.translate(x, y);
      Color saved = g.getColor();

      g.setColor(Color.BLUE);
      g.fillRect(0, 0, iconSize, (int) ((double) iconSize / 3) + 1);

      g.setColor(Color.WHITE);
      g.fillRect(0, (int) ((double) iconSize / 3), iconSize, iconSize * 5 / 6);

      g.setColor(Color.GRAY);
      g.drawRect(0, 0, iconSize, iconSize);

      g.setColor(saved);
      g.translate(-x, -y);
    }
  }

  /** The default JDesktopIcon width. */
  private static final int iconWidth = 160;

  /** The default JDesktopIcon height */
  private static final int iconHeight = 35;

  /** The JDesktopIcon this UI delegate represents. */
  protected JDesktopIcon desktopIcon;

  /** The JInternalFrame associated with the JDesktopIcon. */
  protected JInternalFrame frame;

  /** The MouseListener responsible for reacting to MouseEvents on the JDesktopIcon. */
  private transient MouseInputListener mouseHandler;

  /** The Button in the JDesktopIcon responsible for deiconifying it.
   * This is package-private to avoid an accessor method. */
  transient BoundButton button;

  /** The PropertyChangeListener listening to the JDesktopIcon. */
  private transient PropertyChangeListener propertyHandler;
  
  /** The default icon used when no frame icon is given by the JInternalFrame. */
  static Icon defaultIcon = new InternalFrameDefaultMenuIcon();

  /**
   * This is a helper class that is used in JDesktopIcon and gives the Button a predetermined size.
   */
  private class BoundButton extends JButton
  {
    /**
     * Creates a new BoundButton object.
     *
     * @param title The title of the button.
     */
    public BoundButton(String title)
    {
      super(title);
    }

    /**
     * This method returns a standard size (based on the defaults of the JDesktopIcon) and the insets.
     *
     * @return The preferred size of the JDesktopIcon.
     */
    public Dimension getPreferredSize()
    {
      Insets insets = desktopIcon.getInsets();
      return new Dimension(iconWidth - insets.left - insets.right,
                           iconHeight - insets.top - insets.bottom);
    }

    /**
     * This method returns the minimum size of the button.
     *
     * @return The minimum size of the button.
     */
    public Dimension getMinimumSize()
    {
      return getPreferredSize();
    }

    /**
     * This method returns the maximum size of the button.
     *
     * @return The maximum size of the button.
     */
    public Dimension getMaximumSize()
    {
      return getPreferredSize();
    }
  }

  /**
   * Creates a new BasicDesktopIconUI object.
   */
  public BasicDesktopIconUI()
  {
  }

  /**
   * This method creates a new BasicDesktopIconUI for the given JComponent.
   *
   * @param c The JComponent to create a UI for.
   *
   * @return A new BasicDesktopIconUI.
   */
  public static ComponentUI createUI(JComponent c)
  {
    return new BasicDesktopIconUI();
  }

  /**
   * This method installs the UI for the given JComponent.
   *
   * @param c The JComponent to install this UI for.
   */
  public void installUI(JComponent c)
  {
    if (c instanceof JDesktopIcon)
      {
	desktopIcon = (JDesktopIcon) c;
	desktopIcon.setLayout(new BorderLayout());
	frame = desktopIcon.getInternalFrame();

	installDefaults();
	installComponents();
	installListeners();

	desktopIcon.setOpaque(true);
      }
  }

  /**
   * This method uninstalls the UI for the given JComponent.
   *
   * @param c The JComponent to uninstall this UI for.
   */
  public void uninstallUI(JComponent c)
  {
    desktopIcon.setOpaque(false);
    
    uninstallListeners();
    uninstallComponents();
    uninstallDefaults();
    
    frame = null;
    desktopIcon.setLayout(null);
    desktopIcon = null;
  }

  /**
   * This method installs the necessary sub components for the JDesktopIcon.
   */
  protected void installComponents()
  {
    // Try to create a button based on what the frame's
    // state is currently
    button = new BoundButton(frame.getTitle());
    button.setHorizontalAlignment(SwingConstants.LEFT);
    button.setHorizontalTextPosition(SwingConstants.TRAILING);

    Icon use = frame.getFrameIcon();
    if (use == null)
      use = defaultIcon;
    button.setIcon(use);

    desktopIcon.add(button, SwingConstants.CENTER);
  }

  /**
   * This method uninstalls the sub components for the JDesktopIcon.
   */
  protected void uninstallComponents()
  {
    desktopIcon.remove(button);
    
    button = null;
  }

  /**
   * This method installs the listeners needed by this UI.
   */
  protected void installListeners()
  {
    mouseHandler = createMouseInputListener();

    desktopIcon.addMouseMotionListener(mouseHandler);
    desktopIcon.addMouseListener(mouseHandler);

    propertyHandler = new PropertyChangeListener()
        {
	  public void propertyChange(PropertyChangeEvent e)
	  {
	    if (e.getPropertyName().equals(JInternalFrame.TITLE_PROPERTY))
	      button.setText(desktopIcon.getInternalFrame().getTitle());
	    else if (e.getPropertyName().equals(JInternalFrame.FRAME_ICON_PROPERTY))
	      {
		Icon use = desktopIcon.getInternalFrame().getFrameIcon();
		if (use == null)
		  use = defaultIcon;
		button.setIcon(use);
	      }
	    desktopIcon.revalidate();
	    desktopIcon.repaint();
	  }
        };
    frame.addPropertyChangeListener(propertyHandler);

    button.addActionListener(new ActionListener()
        {
	  public void actionPerformed(ActionEvent e)
	  {
            deiconize();
	  }
        });
  }

  /**
   * This method uninstalls the listeners needed by the UI.
   */
  protected void uninstallListeners()
  {
    // button is nulled so no need to remove it.
    
    frame.removePropertyChangeListener(propertyHandler);
    propertyHandler = null;
    
    desktopIcon.removeMouseMotionListener(mouseHandler);
    desktopIcon.removeMouseListener(mouseHandler);
  }

  /**
   * This method installs the defaults for the JDesktopIcon.
   */
  protected void installDefaults()
  {
    // FIXME: Move border to defaults.
    desktopIcon.setBorder(new DesktopIconBorder());  
  }

  /**
   * This method uninstalls the defaults for the JDesktopIcon.
   */
  protected void uninstallDefaults()
  {
    desktopIcon.setBorder(null);
  }

  /**
   * This method creates a new MouseInputListener for the JDesktopIcon.
   *
   * @return A new MouseInputListener.
   */
  protected MouseInputListener createMouseInputListener()
  {
    return new MouseInputHandler();
  }

  /**
   * This method returns the preferred size for the given JComponent.
   *
   * @param c The JComponent to find a preferred size for.
   *
   * @return The preferred size.
   */
  public Dimension getPreferredSize(JComponent c)
  {
    return new Dimension(iconWidth, iconHeight);
  }

  /**
   * This method returns the minimum size for the given JComponent.
   *
   * @param c The JComponent to find a minimum size for.
   *
   * @return The minimum size.
   */
  public Dimension getMinimumSize(JComponent c)
  {
    return getPreferredSize(c);
  }

  /**
   * This method returns the maximum size for the given JComponent.
   *
   * @param c The JComponent to find a maximum size for.
   *
   * @return The maximum size.
   */
  public Dimension getMaximumSize(JComponent c)
  {
    return getPreferredSize(c);
  }

  /**
   * This method returns the insets of the given JComponent.
   *
   * @param c The JComponent to find insets for.
   *
   * @return The insets of the given JComponent.
   */
  public Insets getInsets(JComponent c)
  {
    return c.getInsets();
  }

  /**
   * This method deiconizes the JInternalFrame associated with the JDesktopIcon.
   */
  public void deiconize() 
  {
    try
    {
      frame.setIcon(false);
    }
    catch (PropertyVetoException pve)
    {
    }
  }
}