如何更改 jtree 节点的背景颜色

Question

I am having a.netbeans project with jtree and DefaultMutableTreeNode. I have to search a node in the tree by its name and want to highlight it, for highlighting I think I will change the background color of the node.

For searching the node I made a func, `

public DefaultMutableTreeNode searchNode(DefaultMutableTreeNode treeRoot, String nodeStr) {
        DefaultMutableTreeNode node = null;
        Enumeration e = treeRoot.breadthFirstEnumeration();
        while (e.hasMoreElements()) {
          node = (DefaultMutableTreeNode) e.nextElement();
          if (nodeStr.equals(node.getUserObject().toString())) {
            return node;
          }
        }
        return null;
    }

now I can search a desired node by its name, DefaultMutableTreeNode searched = searchNode(root, "mynode");`

it gives me the node but now I am stuck how to highlight the searched node returned by this function, I need to make something like, searched.changeBackgroundColor(Color.RED); to highlight the searched node.

Please help me to do it. Thanks

Answer 1

The model, in this case DefaultMutableTreeNode , doesn't do its own rendering. It's just for storing data.

All rendering is done through implementations of TreeCellRenderer . There is one provided implementation, DefaultTreeCellRenderer .

The best way to go forward is to create a sub class of DefaultTreeCellRenderer , and override its getTreeCellRendererComponent method. For example:

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

    Component component = super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf, row, hasFocus);
    if (value == searched) {
        component.setBackground(Color.RED);
    }
    return component;
}