Java TreeCeleditor的fireEditingStopped（）方法

我有一些swing教程中的示例代码。在代码中，我们向面板添加一个JTree，然后定制渲染和编辑树。我们希望树的叶子是JCheckbox，所以用户可以选中或取消选中每一个

作为一个自定义TreeCellEditor，我创建了一个实现TreeCellEditor并扩展AbstractCellEditor的类，因此在我的类中，我只覆盖这些树方法：

public boolean isCellEditable(EventObject e)
public Object getCellEditorValue()
public Component getTreeCellEditorComponent(JTree arg0, Object arg1, boolean arg2, boolean arg3, boolean arg4, int arg5)

在最后一个类中，它检查用户是否尝试编辑叶，它调用复选框的ItemListener中的fireEditingStopped（）方法（叶被呈现为复选框）。是威德！我们仍然没有编辑任何内容，fire编辑停止了！那么这个方法到底是什么呢

脚注：我们将每个叶的UserObject设置为ServerInfo类的一个实例，其中有3个字段：name、id和checked

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.MouseEvent;
import java.util.EventObject;

import javax.swing.AbstractCellEditor;
import javax.swing.ImageIcon;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTree;
import javax.swing.SwingUtilities;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.TreeCellEditor;
import javax.swing.tree.TreeCellRenderer;
import javax.swing.tree.TreePath;


public class Main extends JFrame{
    private MPanel mPanel;

    public Main() {
        mPanel = new MPanel();
        this.setSize(400,400);
        this.setLayout(new BorderLayout());
        this.add(mPanel,BorderLayout.CENTER);
        this.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new Main();
            }
        });
    }
}
class MPanel extends JPanel{
    private JTree serverTree;
    public MPanel() {
        serverTree = new JTree(createTree());
        serverTree.setCellRenderer(new ServerTreeCellRenderer());
        serverTree.setCellEditor(new ServerTreeCellEditor());
        this.setLayout(new BorderLayout());
        this.add(serverTree, BorderLayout.CENTER);
    }
    private DefaultMutableTreeNode createTree() {
        DefaultMutableTreeNode top = new DefaultMutableTreeNode("Servers");

        DefaultMutableTreeNode branch1 = new DefaultMutableTreeNode("USA");
        DefaultMutableTreeNode server1 = new DefaultMutableTreeNode(new ServerInfo("New York",1,true));

        branch1.add(server1);

        DefaultMutableTreeNode branch2 = new DefaultMutableTreeNode("UK");
        DefaultMutableTreeNode server4 = new DefaultMutableTreeNode(new ServerInfo("London", 4, false));
        branch2.add(server4);

        top.add(branch1);
        top.add(branch2);

        return top;
    }
}
////////////////////////////////////////////
class ServerInfo{
    private String name;
    private int id;
    private boolean selected;
    public ServerInfo(String name, int id, boolean selected) {
        this.name = name;
        this.id = id;
        this.selected=selected;
    }
    public String getName() {
        return name;
    }
    public boolean isChecked() {
        return selected;
    }
    public void setChecked(boolean selected) {
        this.selected = selected;
    }

    public String toString() {
        return id + " : " + name + "-->" + selected;
    }
}
////////////////////////////////
class ServerTreeCellRenderer implements TreeCellRenderer {
    private JCheckBox leafRenderer;
    private DefaultTreeCellRenderer nonLeafNode;

    public ServerTreeCellRenderer() {
    }

    @Override
    public Component getTreeCellRendererComponent(JTree tree, Object node, boolean selected, boolean expanded,
            boolean leaf, int row, boolean hasFocus) {
        DefaultMutableTreeNode theNode = (DefaultMutableTreeNode)node;

        if(leaf) {
            ServerInfo info = (ServerInfo)theNode.getUserObject();
            leafRenderer = new JCheckBox(info.getName());
            leafRenderer.setSelected(info.isChecked());
            return leafRenderer;
        }else {
            nonLeafNode = new DefaultTreeCellRenderer();
            //nonLeafNode.setClosedIcon(new ImageIcon(getClass().getResource("/images/earthplus.gif")));
            //nonLeafNode.setOpenIcon(new ImageIcon(getClass().getResource("/images/earth.gif")));
            return nonLeafNode.getTreeCellRendererComponent(tree, node, selected, expanded, leaf, row, hasFocus);
        }
    }
}
/////////////////////////////////////////

class ServerTreeCellEditor extends AbstractCellEditor implements TreeCellEditor {
    private ServerTreeCellRenderer renderer;
    private ServerInfo info;
    private JCheckBox checkBox;

    @Override
    public Object getCellEditorValue() {
        info.setChecked(checkBox.isSelected());
        return info;
    }

    @Override
    public boolean isCellEditable(EventObject e) {
        if(!(e instanceof MouseEvent)) return false;
        MouseEvent me = (MouseEvent)e;
        JTree tree = (JTree)e.getSource();
        TreePath path = tree.getPathForLocation(me.getX(),me.getY());
        if(path==null) return false;
        Object lastComp = path.getLastPathComponent();
        if(lastComp==null) return false;
        DefaultMutableTreeNode node = (DefaultMutableTreeNode )lastComp;
        return node.isLeaf();
    }


    @Override
    public Component getTreeCellEditorComponent(JTree tree, Object value, boolean isSelected, boolean expanded, boolean leaf,int row) {

        Component comp = renderer.getTreeCellRendererComponent(tree,value,isSelected,expanded,leaf,row, true);
        if(leaf){
            DefaultMutableTreeNode treeNode=(DefaultMutableTreeNode)value;
            info = (ServerInfo)treeNode.getUserObject();
            checkBox = (JCheckBox)comp;
            ItemListener itemListener = new ItemListener(){
                public void itemStateChanged(ItemEvent e){
                    fireEditingStopped();
                    checkBox.removeItemListener(this);
                }
            };
            checkBox.addItemListener(itemListener);
        }
        return comp;
    }
}

---

你能发布一个可复制的最小示例吗？@vincenzopalazzo我能，但在我的代码中我不能编辑复选框，我想这可能是因为这个fireEditingStopped方法！无论如何，我在这里放了一个可运行的最小代码，谢谢

ItemListener

，当

JCheckBox

的状态更改（选中/取消选中）时，将调用

ItemListener

，我个人会使用

ActionListener

，副作用更少，但这就是我。因此，在调用

itemStateChanged

时，您已经编辑了值的状态，因此调用stop editing是一项有效的任务，这将迫使

JTree

调用

getCellEditorValue

并修改模型状态。好吧，您会因为这一点而讨厌您自己（我知道当我意识到这一点时，我不禁呻吟）。添加

serverTree.setEditable（true）给你
MPanel
构造函数。这将使表格可编辑-但您将在编辑器中得到一个
NullPointerException
，但我很确定您应该能够修复它；）@非常感谢