How to highlight a node of JTree with diffrent colour when node is selected

How to highlight a node of JTree with diffrent colour when node is selected by mouse click.  As soon as mouse is clicked on the node, node should be selected (highlighted) with diffrent colour.

Siddhartha
beraAsked:
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fmaritatoCommented:
You have to make a customized cell renderer for your tree.
I have attached an example for you. Note that you must specify
a paint method, because simply using the setBackground method
for JLabel does not work. Also note that you can specify any color
you want by changing the SelectedBackgroundColor variable.
In your main program call tree.setCellRenderer(thisRenderer);

Example:

import com.sun.java.swing.JLabel;
import com.sun.java.swing.Icon;
import com.sun.java.swing.UIManager;
import com.sun.java.swing.JTree;
import com.sun.java.swing.tree.TreeCellRenderer;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Component;

public class CDSTreeCellRenderer extends JLabel
  implements TreeCellRenderer {
 
  // Folder Icons
  private Icon  closedIcon = UIManager.getIcon("Tree.openIcon");
  private Icon  openIcon   = UIManager.getIcon("Tree.closedIcon");

  // Is this node selected?
  private boolean selected;

  // Important Colors
  private Color SelectedBackgroundColor =
    UIManager.getColor("Tree.backgroundSelectionColor");
  private  Color SelectedForegroundColor =
    UIManager.getColor("Tree.textSelectionColor");  
  private  Color NonSelectedBackgroundColor =
    UIManager.getColor("Tree.backgroundNonSelectionColor");
  private  Color NonSelectedForegroundColor =
    UIManager.getColor("Tree.textNonSelectionColor");
  private  Color BorderSelectionColor =
    UIManager.getColor("Tree.borderSelectionColor");
 
  /**********************************************************************/
  public CDSTreeCellRenderer() {
   
  }

  /**********************************************************************/
  public Component getTreeCellRendererComponent(JTree   tree,
                                    Object  value,
                                    boolean selected,
                                    boolean expanded,
                                    boolean leaf,
                                    int     row,
                                    boolean hasFocus) {

    String stringValue  = tree.convertValueToText(value,
                                      selected,
                                      expanded,
                                      leaf,
                                      row,
                                      hasFocus);
    setText(stringValue);
    if (expanded) {
      setIcon(openIcon);
    } else {
      setIcon(closedIcon);
    }

    if(selected) {
      setForeground(SelectedForegroundColor);
    } else {
      setForeground(NonSelectedForegroundColor);
    }

    this.selected = selected;
   
    return this;
  }

  /**********************************************************************/
  public void paint (Graphics g) {
   
    if (selected) {
      g.setColor(SelectedBackgroundColor);
    } else {
      g.setColor(NonSelectedBackgroundColor);      
    }

    Icon currentI = getIcon();

    if (currentI != null && getText() != null) {
      int offset = (currentI.getIconWidth() + getIconTextGap());
      g.fillRect(offset,
             0,
             getWidth() - 1 - offset,
             getHeight() - 1);
    } else {
      g.fillRect(0,
             0,
             getWidth() - 1,
             getHeight() - 1);
    }
     
    if (selected) {
      g.setColor(BorderSelectionColor);
      g.drawRect(0,
             0,
             getWidth() - 1,
             getHeight() - 1);
    }

    super.paint(g);
  }
}
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