Java Swing Tips: Highlight entire JTree row on selection

2011/02/28

Highlight entire JTree row on selection

Code

final Color SELC = new Color(100,150,200);
JTree tree = new JTree() {
  @Override public void paintComponent(Graphics g) {
    g.setColor(getBackground());
    g.fillRect(0,0,getWidth(),getHeight());
    if(getSelectionCount()>0) {
      for(int i: getSelectionRows()) {
        Rectangle r = getRowBounds(i);
        g.setColor(SELC);
        g.fillRect(0, r.y, getWidth(), r.height);
      }
    }
    super.paintComponent(g);
    if(getLeadSelectionPath()!=null) {
      Rectangle r = getRowBounds(getRowForPath(getLeadSelectionPath()));
      g.setColor(SELC.darker());
      g.drawRect(0, r.y, getWidth()-1, r.height-1);
    }
  }
};
tree.setUI(new javax.swing.plaf.basic.BasicTreeUI() {
  @Override public Rectangle getPathBounds(JTree tree, TreePath path) {
    if(tree != null && treeState != null) {
      return getPathBounds(path, tree.getInsets(), new Rectangle());
    }
    return null;
  }
  private Rectangle getPathBounds(TreePath path, Insets insets, Rectangle bounds) {
    bounds = treeState.getBounds(path, bounds);
    if(bounds != null) {
      bounds.width = tree.getWidth();
      bounds.y += insets.top;
    }
    return bounds;
  }
});
tree.setOpaque(false);