basiclistui.java

gcc的组建

/* BasicListUI.java --
   Copyright (C) 2002, 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.Component;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ComponentAdapter;
import java.awt.event.ComponentEvent;
import java.awt.event.ComponentListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.awt.event.MouseEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.AbstractAction;
import javax.swing.ActionMap;
import javax.swing.CellRendererPane;
import javax.swing.DefaultListSelectionModel;
import javax.swing.InputMap;
import javax.swing.JComponent;
import javax.swing.JList;
import javax.swing.JViewport;
import javax.swing.KeyStroke;
import javax.swing.ListCellRenderer;
import javax.swing.ListModel;
import javax.swing.ListSelectionModel;
import javax.swing.LookAndFeel;
import javax.swing.UIDefaults;
import javax.swing.UIManager;
import javax.swing.event.ListDataEvent;
import javax.swing.event.ListDataListener;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.event.MouseInputListener;
import javax.swing.plaf.ActionMapUIResource;
import javax.swing.plaf.ComponentUI;
import javax.swing.plaf.InputMapUIResource;
import javax.swing.plaf.ListUI;

/**
 * The Basic Look and Feel UI delegate for the 
 * JList.
 */
public class BasicListUI extends ListUI
{

  /**
   * A helper class which listens for {@link ComponentEvent}s from
   * the JList.
   */
  private class ComponentHandler extends ComponentAdapter {

    /**
     * Called when the component is hidden. Invalidates the internal
     * layout.
     */
    public void componentResized(ComponentEvent ev) {
      BasicListUI.this.damageLayout();
    }
  }

  /**
   * A helper class which listens for {@link FocusEvent}s
   * from the JList.
   */
  public class FocusHandler implements FocusListener
  {
    /**
     * Called when the JList acquires focus.
     *
     * @param e The FocusEvent representing focus acquisition
     */
    public void focusGained(FocusEvent e)
    {
      repaintCellFocus();
    }

    /**
     * Called when the JList loses focus.
     *
     * @param e The FocusEvent representing focus loss
     */
    public void focusLost(FocusEvent e)
    {
      repaintCellFocus();
    }

    /**
     * Helper method to repaint the focused cell's 
     * lost or acquired focus state.
     */
    protected void repaintCellFocus()
    {
      // TODO: Implement this properly.
    }
  }

  /**
   * A helper class which listens for {@link ListDataEvent}s generated by
   * the {@link JList}'s {@link ListModel}.
   *
   * @see javax.swing.JList#getModel()
   */
  public class ListDataHandler implements ListDataListener
  {
    /**
     * Called when a general change has happened in the model which cannot
     * be represented in terms of a simple addition or deletion.
     *
     * @param e The event representing the change
     */
    public void contentsChanged(ListDataEvent e)
    {
      BasicListUI.this.damageLayout();
    }

    /**
     * Called when an interval of objects has been added to the model.
     *
     * @param e The event representing the addition
     */
    public void intervalAdded(ListDataEvent e)
    {
      BasicListUI.this.damageLayout();
    }

    /**
     * Called when an inteval of objects has been removed from the model.
     *
     * @param e The event representing the removal
     */
    public void intervalRemoved(ListDataEvent e)
    {
      BasicListUI.this.damageLayout();
    }
  }

  /**
   * A helper class which listens for {@link ListSelectionEvent}s
   * from the {@link JList}'s {@link ListSelectionModel}.
   */
  public class ListSelectionHandler implements ListSelectionListener
  {
    /**
     * Called when the list selection changes.  
     *
     * @param e The event representing the change
     */
    public void valueChanged(ListSelectionEvent e)
    {
      int index1 = e.getFirstIndex();
      int index2 = e.getLastIndex();
      Rectangle damaged = getCellBounds(list, index1, index2);
      list.repaint(damaged);
    }
  }

  /**
   * This class is used to mimmic the behaviour of the JDK when registering
   * keyboard actions.  It is the same as the private class used in JComponent
   * for the same reason.  This class receives an action event and dispatches
   * it to the true receiver after altering the actionCommand property of the
   * event.
   */
  private static class ActionListenerProxy
    extends AbstractAction
  {
    ActionListener target;
    String bindingCommandName;

    public ActionListenerProxy(ActionListener li, 
                               String cmd)
    {
      target = li;
      bindingCommandName = cmd;
    }

    public void actionPerformed(ActionEvent e)
    {
      ActionEvent derivedEvent = new ActionEvent(e.getSource(),
                                                 e.getID(),
                                                 bindingCommandName,
                                                 e.getModifiers());
      target.actionPerformed(derivedEvent);
    }
  }
  
  class ListAction extends AbstractAction
  {
    public void actionPerformed (ActionEvent e)
    {
      int lead = list.getLeadSelectionIndex();
      int max = list.getModel().getSize() - 1;
      DefaultListSelectionModel selModel = (DefaultListSelectionModel)list.getSelectionModel();
      String command = e.getActionCommand();
      // Do nothing if list is empty
      if (max == -1)
        return;
      
      if (command.equals("selectNextRow"))
        {
          selectNextIndex();
        }
      else if (command.equals("selectPreviousRow"))
        {
          selectPreviousIndex();
        }
      else if (command.equals("clearSelection"))
        {
          list.clearSelection();
        }
      else if (command.equals("selectAll"))
        {
          list.setSelectionInterval(0, max);
          // this next line is to restore the lead selection index to the old
          // position, because select-all should not change the lead index
          list.addSelectionInterval(lead, lead);
        }
      else if (command.equals("selectLastRow"))
        {
          list.setSelectedIndex(list.getModel().getSize() - 1); 
        }
      else if (command.equals("selectLastRowChangeLead"))
        {
          selModel.moveLeadSelectionIndex(list.getModel().getSize() - 1);
        }
      else if (command.equals("scrollDownExtendSelection"))
        {
          int target;
          if (lead == list.getLastVisibleIndex())
            {
              target = Math.min
                (max, lead + (list.getLastVisibleIndex() -
                    list.getFirstVisibleIndex() + 1));
            }
          else
            target = list.getLastVisibleIndex();
          selModel.setLeadSelectionIndex(target);
        }
      else if (command.equals("scrollDownChangeLead"))
        {
          int target;
          if (lead == list.getLastVisibleIndex())
            {
              target = Math.min
                (max, lead + (list.getLastVisibleIndex() -
                    list.getFirstVisibleIndex() + 1));
            }
          else
            target = list.getLastVisibleIndex();
          selModel.moveLeadSelectionIndex(target);
        }
      else if (command.equals("scrollUpExtendSelection"))
        {
          int target;
          if (lead == list.getFirstVisibleIndex())
            {
              target = Math.max 
                (0, lead - (list.getLastVisibleIndex() - 
                    list.getFirstVisibleIndex() + 1));
            }
          else
            target = list.getFirstVisibleIndex();
          selModel.setLeadSelectionIndex(target);
        }
      else if (command.equals("scrollUpChangeLead"))
        {
          int target;
          if (lead == list.getFirstVisibleIndex())
            {
              target = Math.max 
                (0, lead - (list.getLastVisibleIndex() - 
                    list.getFirstVisibleIndex() + 1));
            }
          else
            target = list.getFirstVisibleIndex();
          selModel.moveLeadSelectionIndex(target);
        }
      else if (command.equals("selectNextRowExtendSelection"))
        {
          selModel.setLeadSelectionIndex(Math.min(lead + 1,max));
        }
      else if (command.equals("selectFirstRow"))
        {
          list.setSelectedIndex(0);
        }
      else if (command.equals("selectFirstRowChangeLead"))
          {
            selModel.moveLeadSelectionIndex(0);
          }
      else if (command.equals("selectFirstRowExtendSelection"))
        {
          selModel.setLeadSelectionIndex(0);
        }
      else if (command.equals("selectPreviousRowExtendSelection"))
        {
          selModel.setLeadSelectionIndex(Math.max(0,lead - 1));
        }
      else if (command.equals("scrollUp"))
        {
          int target;
          if (lead == list.getFirstVisibleIndex())
            {
              target = Math.max 
                (0, lead - (list.getLastVisibleIndex() - 
                    list.getFirstVisibleIndex() + 1));
            }
          else
            target = list.getFirstVisibleIndex();
          list.setSelectedIndex(target);          
        }
      else if (command.equals("selectLastRowExtendSelection"))
        {
          selModel.setLeadSelectionIndex(list.getModel().getSize() - 1);
        }
      else if (command.equals("scrollDown"))
        {
          int target;
          if (lead == list.getLastVisibleIndex())
            {
              target = Math.min
                (max, lead + (list.getLastVisibleIndex() -
                    list.getFirstVisibleIndex() + 1));
            }
          else
            target = list.getLastVisibleIndex();
          list.setSelectedIndex(target);
        }
      else if (command.equals("selectNextRowChangeLead"))
          {
            if (selModel.getSelectionMode() != ListSelectionModel.MULTIPLE_INTERVAL_SELECTION)
              selectNextIndex();
            else
              {
                selModel.moveLeadSelectionIndex(Math.min(max, lead + 1));
              }
          }
      else if (command.equals("selectPreviousRowChangeLead"))
        {
          if (selModel.getSelectionMode() != ListSelectionModel.MULTIPLE_INTERVAL_SELECTION)
            selectPreviousIndex();
          else
            {
              selModel.moveLeadSelectionIndex(Math.max(0, lead - 1));
            }
        }      
      else if (command.equals("addToSelection"))
        {
          list.addSelectionInterval(lead, lead);
        }
      else if (command.equals("extendTo"))
        {
          selModel.setSelectionInterval(selModel.getAnchorSelectionIndex(),
                                        lead);
        }
      else if (command.equals("toggleAndAnchor"))
        {
          if (!list.isSelectedIndex(lead))
            list.addSelectionInterval(lead, lead);
          else
            list.removeSelectionInterval(lead, lead);
          selModel.setAnchorSelectionIndex(lead);
        }
      else 
        {
          // DEBUG: uncomment the following line to print out 
          // key bindings that aren't implemented yet
          
          // System.out.println ("not implemented: "+e.getActionCommand());
        }
      
      list.ensureIndexIsVisible(list.getLeadSelectionIndex());
    }
  }
     
  /**
   * A helper class which listens for {@link MouseEvent}s 
   * from the {@link JList}.
   */
  public class MouseInputHandler implements MouseInputListener
  {
    /**
     * Called when a mouse button press/release cycle completes
     * on the {@link JList}
     *
     * @param event The event representing the mouse click
     */
    public void mouseClicked(MouseEvent event)
    {
      Point click = event.getPoint();
      int index = locationToIndex(list, click);
      if (index == -1)
        return;
      if (event.isShiftDown())
        {
          if (list.getSelectionMode() == ListSelectionModel.SINGLE_SELECTION)
            list.setSelectedIndex(index);
          else if (list.getSelectionMode() == 
                   ListSelectionModel.SINGLE_INTERVAL_SELECTION)
            // COMPAT: the IBM VM is compatible with the following line of code.
            // However, compliance with Sun's VM would correspond to replacing 
            // getAnchorSelectionIndex() with getLeadSelectionIndex().This is 
            // both unnatural and contradictory to the way they handle other 
            // similar UI interactions.
            list.setSelectionInterval(list.getAnchorSelectionIndex(), index);
          else
            // COMPAT: both Sun and IBM are compatible instead with:
            // list.setSelectionInterval
            //     (list.getLeadSelectionIndex(),index);
            // Note that for IBM this is contradictory to what they did in 
            // the above situation for SINGLE_INTERVAL_SELECTION.  
            // The most natural thing to do is the following: