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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:

Descriptions of supported hints: Angled, Horizontal, and None
Hint Description
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 class="striped"> * <caption>Descriptions of supported hints: Angled, Horizontal, and None * </caption> * <thead> * <tr> * <th scope="col">Hint * <th scope="col">Description * </thead> * <tbody> * <tr> * <th scope="row">Angled * <td>A line is drawn connecting the child to the parent. For handling of * the root node refer to {@link JTree#setRootVisible} and * {@link JTree#setShowsRootHandles}. * <tr> * <th scope="row">Horizontal * <td>A horizontal line is drawn dividing the children of the root node. * <tr> * <th scope="row">None * <td>Do not draw any visual indication between nodes. * </tbody> * </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();
Constructs the MetalTreeUI.
Params:
  • x – a component
Returns:the instance of the MetalTreeUI
/** * Constructs the {@code MetalTreeUI}. * * @param x a component * @return the instance of the {@code MetalTreeUI} */
public static ComponentUI createUI(JComponent x) { return new MetalTreeUI(); }
Constructs the MetalTreeUI.
/** * Constructs the {@code 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); }
Converts between the string passed into the client property and the internal representation (currently and int)
Params:
  • lineStyleFlag – a flag
/** * Converts between the string passed into the client property * and the internal representation (currently and int) * * @param lineStyleFlag a flag */
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; } } }
Returns true if a point with X coordinate mouseX and Y coordinate mouseY is in expanded control.
Params:
  • row – a row
  • rowLevel – a row level
  • mouseX – X coordinate
  • mouseY – Y coordinate
Returns:true if a point with X coordinate mouseX and Y coordinate mouseY is in expanded control.
/** * Returns {@code true} if a point with X coordinate {@code mouseX} * and Y coordinate {@code mouseY} is in expanded control. * * @param row a row * @param rowLevel a row level * @param mouseX X coordinate * @param mouseY Y coordinate * @return {@code true} if a point with X coordinate {@code mouseX} * and Y coordinate {@code mouseY} is in expanded control. */
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); } }
Paints the horizontal separators.
Params:
  • g – an instance of Graphics
  • c – a component
/** * Paints the horizontal separators. * * @param g an instance of {@code Graphics} * @param c a component */
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 }