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 * {@link javax.swing.JTree#setRootVisible} and * {@link javax.swing.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 impratical 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
* @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)
*
*/
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 */
class LineListener implements PropertyChangeListener {
public void propertyChange(PropertyChangeEvent e) {
String name = e.getPropertyName();
if ( name.equals( LINE_STYLE ) ) {
decodeLineStyle(e.getNewValue());
}
}
} // end class PaletteListener
}