JTree with JCheckbox 收藏

JTree with JCheckbox 收藏
一个使JTree节点有JCheckbox外观的类
   分类：那段代码

这是刚刚写完的，一个使JTree节点有JCheckbox外观的类。
最近的工作需要，对项目的菜单加入权限设置。
所以打算用树型控件来进行操作，没办法，只好改造swing的JTree了。
网上有个JTree with CheckBoxes的例子

总觉得比较麻烦，正好自己有时间，还是自己写一个吧。
 
代码在下面，贴出来分享一下，没什么时间写文档，大概看一下吧。
基本上就是用一个HashMap记录状态
用一个TreeSelectionListener修改状态
再就是用Renderer修改外观
还有就是也用到了三态的JCheckbox类
这是连接
总体上不是很麻烦，感觉比JTree with CheckBoxes的例子简单多了
只是里面写起来有点饶，呵呵
有更好的方法欢迎提出来讨论，有空我会继续完善的。
 
//MyTreeWithCheckbox.java
 
import javax.swing.JTree;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreeNode;
import java.awt.Component;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.TreePath;
import java.util.*;
/**
 * 自己写的一个使JTree节点有JCheckbox外观的类
 * 用了泛型，所以要jdk1.5编译，之前jdk版本的话把集合类写法改回去就可以了
 *

 * @version 1.0 12/06/2006
 * @author Thatboy
 */
public class MyTreeWithCheckbox {
 //用一个HashMap来保存每个节点的选择状态
    private HashMap hm = new HashMap();
    public MyTreeWithCheckbox(JTree jTree) {
        DefaultMutableTreeNode root = (DefaultMutableTreeNode) jTree.getModel().getRoot();
        for (Enumeration em = root.depthFirstEnumeration(); em.hasMoreElements(); ) {
            hm.put((DefaultMutableTreeNode) em.nextElement(), TristateCheckBox.NOT_SELECTED);
        }
        jTree.setCellRenderer(new MyTreeWithCheckboxRenderer());
        jTree.addTreeSelectionListener(new MyTreeWithCheckboxSelectionListener());
    }
  
    /** 返回所有选中的路径 */
    public TreePath[] getSelectionPaths() {
        Iterator it = hm.keySet().iterator();
        ArrayList al = new ArrayList();
        while (it.hasNext()) {
            DefaultMutableTreeNode o = (DefaultMutableTreeNode) it.next();
            if (o.isLeaf() && ((TristateCheckBox.State) hm.get(o)).equals(TristateCheckBox.SELECTED)) {
                al.add(new TreePath(o.getPath()));
            }
        }
        return (TreePath[]) al.toArray(new TreePath[0]);
    }
    class MyTreeWithCheckboxSelectionListener implements TreeSelectionListener {
        public void valueChanged(TreeSelectionEvent e) {
            JTree jTree = (JTree) (e.getSource());
            DefaultMutableTreeNode node = (DefaultMutableTreeNode) jTree.getLastSelectedPathComponent();
            if (node == null) {
                return;
            }
            // 修改当前节点的状态
            if (((TristateCheckBox.State) hm.get(node)).equals(TristateCheckBox.SELECTED)) {
                hm.put(node, TristateCheckBox.NOT_SELECTED);
            } else {
                hm.put(node, TristateCheckBox.SELECTED);
            }
            updateAllParentNodes(node);
            updateAllChildNodes(node);
            jTree.setSelectionPath(null);
            jTree.repaint();
        }
      
        /** 用递归方法修改从当前节点到根节点的所有节点的状态*/
        public void updateAllParentNodes(DefaultMutableTreeNode node) {
            TristateCheckBox.State status = (TristateCheckBox.State) hm.get(node);
            if (node.isRoot()) {
                return;
            }
            hm.put(node.getParent(), status);
            for (Enumeration em = node.getParent().children(); em.hasMoreElements(); ) {
                DefaultMutableTreeNode tn = (DefaultMutableTreeNode) em.nextElement();
                if (!((TristateCheckBox.State) hm.get(tn)).equals(status)) {
                    hm.put(node.getParent(), TristateCheckBox.DONT_CARE);
                    break;
                }
            }
            updateAllParentNodes((DefaultMutableTreeNode) node.getParent());
        }
      
        /** 用递归方法修改以当前节点为根的子树的所有节点的状态*/
        public void updateAllChildNodes(DefaultMutableTreeNode node) {
            TristateCheckBox.State status = (TristateCheckBox.State) hm.get(node);
            for (Enumeration em = node.depthFirstEnumeration(); em.hasMoreElements(); ) {
                DefaultMutableTreeNode tn = (DefaultMutableTreeNode) em.nextElement();
                hm.put(tn, status);
            }
        }
    }
    class MyTreeWithCheckboxRenderer extends DefaultTreeCellRenderer {
  private static final long serialVersionUID = 1L;
  public Component getTreeCellRendererComponent(JTree tree, Object value, boolean selected,
                boolean expanded, boolean leaf, int row, boolean hasFocus) {
            TristateCheckBox checkBox = new TristateCheckBox(value.toString());
            checkBox.setOpaque(false);
            DefaultMutableTreeNode node = (DefaultMutableTreeNode) value;
            checkBox.setState(((TristateCheckBox.State) hm.get(node)));
            return checkBox;
        }
    }
}
 
//顺便写个测试代码吧 TreeDemo.java
 
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import java.awt.BorderLayout;
public class TreeDemo extends JPanel {
 private JTree tree;
 
 public TreeDemo() {
  this.setLayout(new BorderLayout());
  tree = new JTree();
  //用MyTreeWithCheckbox来实现用JCheckbox做节点的JTree
  new MyTreeWithCheckbox(tree);
  JScrollPane treeView = new JScrollPane(tree);
  treeView.setPreferredSize(new Dimension(500, 400));
  add(treeView);
 }
 private static void createAndShowGUI() {
  JFrame frame = new JFrame("TreeDemo");
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  TreeDemo newContentPane = new TreeDemo();
  newContentPane.setOpaque(true);
  frame.setContentPane(newContentPane);
  frame.pack();
  frame.setVisible(true);
 }
 public static void main(String[] args) {
  javax.swing.SwingUtilities.invokeLater(new Runnable() {
   public void run() {
    createAndShowGUI();
   }
  });
 }
}

本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/xuekui8291/archive/2009/05/11/4168093.aspx