basicsplitpanedivider.java

gcc的组建

/* BasicSplitPaneDivider.java --
   Copyright (C) 2003, 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
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Classpath is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
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
conditions of the GNU General Public License cover the whole
combination.

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
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */


package javax.swing.plaf.basic;

import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Insets;
import java.awt.LayoutManager;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.JButton;
import javax.swing.JSplitPane;
import javax.swing.SwingConstants;
import javax.swing.border.Border;

/**
 * The divider that separates the two parts of a JSplitPane in the Basic look
 * and feel.
 * 
 * <p>
 * Implementation status: We do not have a real implementation yet. Currently,
 * it is mostly a stub to allow compiling other parts of the
 * javax.swing.plaf.basic package, although some parts are already
 * functional.
 * </p>
 *
 * @author Sascha Brawer (brawer_AT_dandelis.ch)
 */
public class BasicSplitPaneDivider extends Container
  implements PropertyChangeListener
{
  /**
   * Determined using the <code>serialver</code> tool of Apple/Sun JDK 1.3.1
   * on MacOS X 10.1.5.
   */
  static final long serialVersionUID = 1463404307042803342L;

  /**
   * The width and height of the little buttons for showing and hiding parts
   * of a JSplitPane in a single mouse click.
   */
  protected static final int ONE_TOUCH_SIZE = 6;

  /** The distance the one touch buttons will sit from the divider's edges. */
  protected static final int ONE_TOUCH_OFFSET = 2;

  /**
   * An object that performs the tasks associated with an ongoing drag
   * operation, or <code>null</code> if the user is currently not dragging
   * the divider.
   */
  protected DragController dragger;

  /**
   * The delegate object that is responsible for the UI of the
   * <code>JSplitPane</code> that contains this divider.
   */
  protected BasicSplitPaneUI splitPaneUI;

  /** The thickness of the divider in pixels. */
  protected int dividerSize;

  /** A divider that is used for layout purposes. */
  protected Component hiddenDivider;

  /** The JSplitPane containing this divider. */
  protected JSplitPane splitPane;

  /**
   * The listener for handling mouse events from both the divider and the
   * containing <code>JSplitPane</code>.
   * 
   * <p>
   * The reason for also handling MouseEvents from the containing
   * <code>JSplitPane</code> is that users should be able to start a drag
   * gesture from inside the JSplitPane, but slightly outisde the divider.
   * </p>
   */
  protected MouseHandler mouseHandler = new MouseHandler();

  /**
   * The current orientation of the containing <code>JSplitPane</code>, which
   * is either {@link javax.swing.JSplitPane#HORIZONTAL_SPLIT} or {@link
   * javax.swing.JSplitPane#VERTICAL_SPLIT}.
   */
  protected int orientation;

  /**
   * The button for showing and hiding the left (or top) component of the
   * <code>JSplitPane</code>.
   */
  protected JButton leftButton;

  /**
   * The button for showing and hiding the right (or bottom) component of the
   * <code>JSplitPane</code>.
   */
  protected JButton rightButton;

  /**
   * The border of this divider. Typically, this will be an instance of {@link
   * javax.swing.plaf.basic.BasicBorders.SplitPaneDividerBorder}.
   *
   * @see #getBorder()
   * @see #setBorder(javax.swing.border.Border)
   */
  private Border border;

  // This is not a pixel count.
  // This int should be able to take 3 values.
  // left (top), middle, right(bottom)
  //    0          1          2

  /**
   * Keeps track of where the divider should be placed when using one touch
   * expand buttons.
   * This is package-private to avoid an accessor method.
   */
  transient int currentDividerLocation = 1;

  /** DOCUMENT ME! */
  private transient Border tmpBorder = new Border()
    {
      public Insets getBorderInsets(Component c)
      {
	return new Insets(2, 2, 2, 2);
      }

      public boolean isBorderOpaque()
      {
	return false;
      }

      public void paintBorder(Component c, Graphics g, int x, int y,
                              int width, int height)
      {
	Color saved = g.getColor();
	g.setColor(Color.BLACK);

	g.drawRect(x + 2, y + 2, width - 4, height - 4);

	g.setColor(saved);
      }
    };

  /**
   * Constructs a new divider.
   *
   * @param ui the UI delegate of the enclosing <code>JSplitPane</code>.
   */
  public BasicSplitPaneDivider(BasicSplitPaneUI ui)
  {
    setLayout(new DividerLayout());
    setBasicSplitPaneUI(ui);
    setDividerSize(splitPane.getDividerSize());
    setBorder(tmpBorder);
  }

  /**
   * Sets the delegate object that is responsible for the UI of the {@link
   * javax.swing.JSplitPane} containing this divider.
   *
   * @param newUI the UI delegate, or <code>null</code> to release the
   *        connection to the current delegate.
   */
  public void setBasicSplitPaneUI(BasicSplitPaneUI newUI)
  {
    /* Remove the connection to the existing JSplitPane. */
    if (splitPane != null)
      {
	splitPane.removePropertyChangeListener(this);
	splitPane.removeMouseListener(mouseHandler);
	splitPane.removeMouseMotionListener(mouseHandler);
	removeMouseListener(mouseHandler);
	removeMouseMotionListener(mouseHandler);
	splitPane = null;
	hiddenDivider = null;
      }

    /* Establish the connection to the new JSplitPane. */
    splitPaneUI = newUI;
    if (splitPaneUI != null)
      splitPane = newUI.getSplitPane();
    if (splitPane != null)
      {
	splitPane.addPropertyChangeListener(this);
	splitPane.addMouseListener(mouseHandler);
	splitPane.addMouseMotionListener(mouseHandler);
	addMouseListener(mouseHandler);
	addMouseMotionListener(mouseHandler);
	hiddenDivider = splitPaneUI.getNonContinuousLayoutDivider();
	orientation = splitPane.getOrientation();
	oneTouchExpandableChanged();
      }
  }

  /**
   * Returns the delegate object that is responsible for the UI of the {@link
   * javax.swing.JSplitPane} containing this divider.
   *
   * @return The UI for the JSplitPane.
   */
  public BasicSplitPaneUI getBasicSplitPaneUI()
  {
    return splitPaneUI;
  }

  /**
   * Sets the thickness of the divider.
   *
   * @param newSize the new width or height in pixels.
   */
  public void setDividerSize(int newSize)
  {
    this.dividerSize = newSize;
  }

  /**
   * Retrieves the thickness of the divider.
   *
   * @return The thickness of the divider.
   */
  public int getDividerSize()
  {
    return dividerSize;
  }

  /**
   * Sets the border of this divider.
   *
   * @param border the new border. Typically, this will be an instance of
   *        {@link
   *        javax.swing.plaf.basic.BasicBorders.SplitPaneBorder}.
   *
   * @since 1.3
   */
  public void setBorder(Border border)
  {
    if (border != this.border)
      {
	Border oldValue = this.border;
	this.border = border;
	firePropertyChange("border", oldValue, border);
      }
  }

  /**
   * Retrieves the border of this divider.
   *
   * @return the current border, or <code>null</code> if no border has been
   *         set.
   *
   * @since 1.3
   */
  public Border getBorder()
  {
    return border;
  }

  /**
   * Retrieves the insets of the divider. If a border has been installed on
   * the divider, the result of calling its <code>getBorderInsets</code>
   * method is returned. Otherwise, the inherited implementation will be
   * invoked.
   *
   * @see javax.swing.border.Border#getBorderInsets(java.awt.Component)
   */
  public Insets getInsets()
  {
    if (border != null)
      return border.getBorderInsets(this);
    else
      return super.getInsets();
  }

  /**
   * Returns the preferred size of this divider, which is
   * <code>dividerSize</code> by <code>dividerSize</code> pixels.
   *
   * @return The preferred size of the divider.
   */
  public Dimension getPreferredSize()
  {
    return getLayout().preferredLayoutSize(this);
  }

  /**
   * Returns the minimal size of this divider, which is
   * <code>dividerSize</code> by <code>dividerSize</code> pixels.
   *
   * @return The minimal size of the divider.
   */
  public Dimension getMinimumSize()
  {
    return getPreferredSize();
  }

  /**
   * Processes events from the <code>JSplitPane</code> that contains this
   * divider.
   *
   * @param e The PropertyChangeEvent.
   */
  public void propertyChange(PropertyChangeEvent e)
  {
    if (e.getPropertyName().equals(JSplitPane.ONE_TOUCH_EXPANDABLE_PROPERTY))
      oneTouchExpandableChanged();
    else if (e.getPropertyName().equals(JSplitPane.ORIENTATION_PROPERTY))
      {
	orientation = splitPane.getOrientation();
	if (splitPane.isOneTouchExpandable())
	  {
	    layout();
	    repaint();
	  }
      }
    else if (e.getPropertyName().equals(JSplitPane.DIVIDER_SIZE_PROPERTY))
      dividerSize = splitPane.getDividerSize();
  }

  /**
   * Paints the divider by painting its border.
   *
   * @param g The Graphics Object to paint with.
   */
  public void paint(Graphics g)
  {
    Dimension dividerSize;

    super.paint(g);
    if (border != null)
      {
	dividerSize = getSize();
	border.paintBorder(this, g, 0, 0, dividerSize.width, dividerSize.height);
      }
  }

  /**
   * Reacts to changes of the <code>oneToughExpandable</code> property of the
   * containing <code>JSplitPane</code>.
   */
  protected void oneTouchExpandableChanged()
  {
    if (splitPane.isOneTouchExpandable())
      {
	leftButton = createLeftOneTouchButton();
	rightButton = createRightOneTouchButton();
	add(leftButton);
	add(rightButton);

	leftButton.addMouseListener(mouseHandler);
	rightButton.addMouseListener(mouseHandler);

	// Set it to 1.
	currentDividerLocation = 1;
      }
    else
      {
	if (leftButton != null && rightButton != null)
	  {
	    leftButton.removeMouseListener(mouseHandler);
	    rightButton.removeMouseListener(mouseHandler);

	    remove(leftButton);
	    remove(rightButton);
	    leftButton = null;
	    rightButton = null;
	  }
      }
    layout();
    repaint();
  }

  /**
   * Creates a button for showing and hiding the left (or top) part of a
   * <code>JSplitPane</code>.
   *
   * @return The left one touch button.
   */
  protected JButton createLeftOneTouchButton()
  {
    int dir = SwingConstants.WEST;
    if (orientation == JSplitPane.VERTICAL_SPLIT)
      dir = SwingConstants.NORTH;
    JButton button = new BasicArrowButton(dir);
    button.setBorder(null);

    return button;
  }

  /**
   * Creates a button for showing and hiding the right (or bottom) part of a
   * <code>JSplitPane</code>.
   *
   * @return The right one touch button.
   */
  protected JButton createRightOneTouchButton()
  {
    int dir = SwingConstants.EAST;
    if (orientation == JSplitPane.VERTICAL_SPLIT)
      dir = SwingConstants.SOUTH;
    JButton button = new BasicArrowButton(dir);
    button.setBorder(null);
    return button;
  }

  /**
   * Prepares the divider for dragging by calling the
   * <code>startDragging</code> method of the UI delegate of the enclosing
   * <code>JSplitPane</code>.
   *
   * @see BasicSplitPaneUI#startDragging()
   */
  protected void prepareForDragging()