JTree中为什么将setRootVisiable(false)后整个tree都不显示了（附代码）

[sunshangjun]

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;



public class TestTree extends JFrame {
public TestTree(){
root=new DefaultMutableTreeNode("root");
tree=new JTree(root);
model=(DefaultTreeModel)tree.getModel();
tree.setVisible(true);
child=new DefaultMutableTreeNode("Color");
child.add(new DefaultMutableTreeNode("blue"));
child.add(new DefaultMutableTreeNode("violet"));
child.add(new DefaultMutableTreeNode("red"));
root.add(child);
setLayout(new BorderLayout());
add(tree,BorderLayout.CENTER);
setVisible(true);
}
private JTree tree;
private DefaultTreeModel model;
private DefaultMutableTreeNode root,child;
}

[aaa2003gf]

根节点不可见,所以都不见了.

[zhuokai]

测试了一下，可以设置根节点不可见，子节点可见的：
import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;

public class TreeTest extends JFrame
{
public TreeTest()
{
root = new DefaultMutableTreeNode("root");
tree = new JTree(root);
model = (DefaultTreeModel) tree.getModel();
tree.setVisible(true);
child = new DefaultMutableTreeNode("Color");
child.add(new DefaultMutableTreeNode("blue"));
child.add(new DefaultMutableTreeNode("violet"));
child.add(new DefaultMutableTreeNode("red"));
root.add(child);

setLayout(new BorderLayout());
add(tree, BorderLayout.CENTER);

tree.expandRow(0);
tree.setRootVisible(false);
}
public static void main(String[] args)
{
JFrame tree = new TreeTest();
tree.setSize(200,100);
tree.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
tree.setVisible(true);
}

private JTree tree;

private DefaultTreeModel model;

private DefaultMutableTreeNode root, child;
}


详见：C:\Program Files\Java\jdk1.5.0_05\demo\jfc\SampleTree\src

[IamHades]

试试getContent().add(new JScollPane(tree),BorderLayout.CENTER);
代替你的add(tree,BorderLayout.CENTER);