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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package javax.swing.plaf.metal;

import javax.swing.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;
import java.beans.*;
import java.io.*;
import java.util.*;
import javax.swing.plaf.*;
import javax.swing.tree.*;

import javax.swing.plaf.basic.*;

The metal look and feel implementation of TreeUI.

MetalTreeUI allows for configuring how to
visually render the spacing and delineation between nodes. The following
hints are supported:

 

   
Angled
   
A line is drawn connecting the child to the parent. For handling of the root node refer to JTree.setRootVisible and JTree.setShowsRootHandles. 
 
 

    
Horizontal
    
A horizontal line is drawn dividing the children of the root node.
 
 

     
None
     
Do not draw any visual indication between nodes.
 


As it is typically impractical to obtain the TreeUI from
the JTree and cast to an instance of MetalTreeUI
you enable this property via the client property
JTree.lineStyle. For example, to switch to
Horizontal style you would do:
tree.putClientProperty("JTree.lineStyle", "Horizontal");

The default is Angled.
Author:
Tom Santos, Steve Wilson (value add stuff)/**
 * The metal look and feel implementation of <code>TreeUI</code>.
 * <p>
 * <code>MetalTreeUI</code> allows for configuring how to
 * visually render the spacing and delineation between nodes. The following
 * hints are supported:
 *
 * <table summary="Descriptions of supported hints: Angled, Horizontal, and None">
 *  <tr>
 *    <th><p style="text-align:left">Angled</p></th>
 *    <td>A line is drawn connecting the child to the parent. For handling
 *          of the root node refer to
 *          {@link javax.swing.JTree#setRootVisible} and
 *          {@link javax.swing.JTree#setShowsRootHandles}.
 *    </td>
 *  </tr>
 *  <tr>
 *     <th><p style="text-align:left">Horizontal</p></th>
 *     <td>A horizontal line is drawn dividing the children of the root node.</td>
 *  </tr>
 *  <tr>
 *      <th><p style="text-align:left">None</p></th>
 *      <td>Do not draw any visual indication between nodes.</td>
 *  </tr>
 * </table>
 *
 * <p>
 * As it is typically impractical to obtain the <code>TreeUI</code> from
 * the <code>JTree</code> and cast to an instance of <code>MetalTreeUI</code>
 * you enable this property via the client property
 * <code>JTree.lineStyle</code>. For example, to switch to
 * <code>Horizontal</code> style you would do:
 * <code>tree.putClientProperty("JTree.lineStyle", "Horizontal");</code>
 * <p>
 * The default is <code>Angled</code>.
 *
 * @author Tom Santos
 * @author Steve Wilson (value add stuff)
 */
public class MetalTreeUI extends BasicTreeUI {

    private static Color lineColor;

    private static final String LINE_STYLE = "JTree.lineStyle";

    private static final String LEG_LINE_STYLE_STRING = "Angled";
    private static final String HORIZ_STYLE_STRING = "Horizontal";
    private static final String NO_STYLE_STRING = "None";

    private static final int LEG_LINE_STYLE = 2;
    private static final int HORIZ_LINE_STYLE = 1;
    private static final int NO_LINE_STYLE = 0;

    private int lineStyle = LEG_LINE_STYLE;
    private PropertyChangeListener lineStyleListener = new LineListener();

    // Boilerplate
    public static ComponentUI createUI(JComponent x) {
        return new MetalTreeUI();
    }

    public MetalTreeUI()
    {
        super();
    }

    protected int getHorizontalLegBuffer()
      {
          return 3;
      }

    public void installUI( JComponent c ) {
        super.installUI( c );
        lineColor = UIManager.getColor( "Tree.line" );

        Object lineStyleFlag = c.getClientProperty( LINE_STYLE );
        decodeLineStyle(lineStyleFlag);
        c.addPropertyChangeListener(lineStyleListener);

    }

    public void uninstallUI( JComponent c) {
         c.removePropertyChangeListener(lineStyleListener);
         super.uninstallUI(c);
    }

    
this function converts between the string passed into the client property
and the internal representation (currently and int)
/** this function converts between the string passed into the client property
      * and the internal representation (currently and int)
      *
      */
    protected void decodeLineStyle(Object lineStyleFlag) {
      if ( lineStyleFlag == null ||
                    lineStyleFlag.equals(LEG_LINE_STYLE_STRING)){
        lineStyle = LEG_LINE_STYLE; // default case
      } else {
          if ( lineStyleFlag.equals(NO_STYLE_STRING) ) {
              lineStyle = NO_LINE_STYLE;
          } else if ( lineStyleFlag.equals(HORIZ_STYLE_STRING) ) {
              lineStyle = HORIZ_LINE_STYLE;
          }
      }

    }

    protected boolean isLocationInExpandControl(int row, int rowLevel,
                                                int mouseX, int mouseY) {
        if(tree != null && !isLeaf(row)) {
            int                     boxWidth;

            if(getExpandedIcon() != null)
                boxWidth = getExpandedIcon().getIconWidth() + 6;
            else
                boxWidth = 8;

            Insets i = tree.getInsets();
            int    boxLeftX = (i != null) ? i.left : 0;


            boxLeftX += (((rowLevel + depthOffset - 1) * totalChildIndent) +
                        getLeftChildIndent()) - boxWidth/2;

            int boxRightX = boxLeftX + boxWidth;

            return mouseX >= boxLeftX && mouseX <= boxRightX;
        }
        return false;
    }

    public void paint(Graphics g, JComponent c) {
        super.paint( g, c );


        // Paint the lines
        if (lineStyle == HORIZ_LINE_STYLE && !largeModel) {
            paintHorizontalSeparators(g,c);
        }
    }

    protected void paintHorizontalSeparators(Graphics g, JComponent c) {
        g.setColor( lineColor );

        Rectangle clipBounds = g.getClipBounds();

        int beginRow = getRowForPath(tree, getClosestPathForLocation
                                     (tree, 0, clipBounds.y));
        int endRow = getRowForPath(tree, getClosestPathForLocation
                             (tree, 0, clipBounds.y + clipBounds.height - 1));

        if ( beginRow <= -1 || endRow <= -1 ) {
            return;
        }

        for ( int i = beginRow; i <= endRow; ++i ) {
            TreePath        path = getPathForRow(tree, i);

            if(path != null && path.getPathCount() == 2) {
                Rectangle       rowBounds = getPathBounds(tree,getPathForRow
                                                          (tree, i));

                // Draw a line at the top
                if(rowBounds != null)
                    g.drawLine(clipBounds.x, rowBounds.y,
                               clipBounds.x + clipBounds.width, rowBounds.y);
            }
        }

    }

    protected void paintVerticalPartOfLeg(Graphics g, Rectangle clipBounds,
                                          Insets insets, TreePath path) {
        if (lineStyle == LEG_LINE_STYLE) {
            super.paintVerticalPartOfLeg(g, clipBounds, insets, path);
        }
    }

    protected void paintHorizontalPartOfLeg(Graphics g, Rectangle clipBounds,
                                            Insets insets, Rectangle bounds,
                                            TreePath path, int row,
                                            boolean isExpanded,
                                            boolean hasBeenExpanded, boolean
                                            isLeaf) {
        if (lineStyle == LEG_LINE_STYLE) {
            super.paintHorizontalPartOfLeg(g, clipBounds, insets, bounds,
                                           path, row, isExpanded,
                                           hasBeenExpanded, isLeaf);
        }
    }

    
This class listens for changes in line style /** This class listens for changes in line style */
    class LineListener implements PropertyChangeListener {
        public void propertyChange(PropertyChangeEvent e) {
            String name = e.getPropertyName();
            if ( name.equals( LINE_STYLE ) ) {
                decodeLineStyle(e.getNewValue());
            }
        }
    } // end class PaletteListener

}