如何解决 JTree 中的显示问题？

Question

我是编程初学者。我想创建总指挥官应用程序。我没有更大的问题，但我无法解决。

要打印我的树，我使用从 JTreeModel 实现的类 TreeConstructor 中的函数 getChild()。它工作得很好，但它不仅打印文件名，还打印文件或目录的所有路径。我想过创建 myJTree 类，该类将从 JTree 类扩展并覆盖打印节点的函数，但实际上我不知道这个函数和她的名字在哪里。

类 TreeConstructor 实现 TreeModel {

//To constructor we need to give path
//From where it it starts painting a tree
protected File root;
public TreeConstructor(File root) { this.root = root; }

//Giving root of a tree
@Override
public Object getRoot() {
    return root;
}

//Function to change root 
public void rootChanger(Object parent) {
    this.root = (File)parent;
}

@Override
public Object getChild(Object parent, int index) {
    String[] children = ((File)parent).list();
    if((children.length<=index)||(children == null))return null;
    return new File((File)parent,children[index]);
}

@Override
public int getChildCount(Object parent) {
    String[] children = ((File)parent).list();
    if(children == null) return 0;
    return children.length;
}

@Override
public boolean isLeaf(Object node) {  return ((File)node).isFile(); }

@Override
public int getIndexOfChild(Object parent, Object child) {
       String[] children = ((File)parent).list();
        if (children == null) return -1;
        String childname = ((File)child).getName();
        for(int i = 0; i < children.length; i++) {
          if (childname.equals(children[i])) return i;
        }
        return -1;
}

@Override
public void valueForPathChanged(TreePath path, Object newValue) {}

@Override
public void addTreeModelListener(TreeModelListener l) {}

@Override
public void removeTreeModelListener(TreeModelListener l) {}

这是我的应用程序： https://i.stack.imgur.com/6AsiV.jpg

我会感谢你的帮助丹尼尔

Answer 1

如果没有进一步的代码示例，我建议您查找以下内容：

1. 使用搜索功能，你不是第一个遇到这个问题的:)

Java JTree from directory (shows full path instead of just the name of the file)

1. 编写自己的渲染器

根据您的实现，这可能是编写自己的 Render 的最简单方法

https://www.logicbig.com/tutorials/java-swing/jtree-renderer.html

Answer 2

如前所述，您需要自己的渲染器。像这样的：

public class FileTreeRenderer extends DefaultTreeCellRenderer {
    @Override
    public Component getTreeCellRendererComponent(JTree tree, Object value, boolean sel, boolean expanded,
            boolean leaf, int row, boolean hasFocus) {
        super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf, row, hasFocus);
        if (value instanceof File) {
            setText(((File) value).getName());
        }
        return this;
    }

}

然后你需要将渲染器设置到你的树中

tree.setCellRenderer(new FileTreeRenderer());

还必须实现 TreeModel 接口中定义的方法，以提供 JTree 的正确工作。特别是添加/删除TreeModelListener。它们用于在您的模型更改时（例如，当用户重命名节点时）提供通知树的可能性。

Answer 3

public class Panels extends JPanel{

    File f1 = new File("C:\\Users");

    public TreeConstructor model = new TreeConstructor(f1);

    public JTree tree = new JTree(model);

    public JTextField pathPlace = new JTextField(100);

    JScrollPane scrollPane = new JScrollPane(tree);

    Panels(){

        pathPlace.setText("C:\\Users");

        tree.addMouseListener(new MouseListener() {

            @Override
            public void mouseClicked(MouseEvent e) {
                if(e.getClickCount()==2) {      
                    System.out.println();
                    repaintingTree(pathPlace, tree, model);
                }
            }

            @Override
            public void mousePressed(MouseEvent e) {
                // TODO Auto-generated method stub

            }

            @Override
            public void mouseReleased(MouseEvent e) {
                // TODO Auto-generated method stub

            }

            @Override
            public void mouseEntered(MouseEvent e) {
                // TODO Auto-generated method stub

            }

            @Override
            public void mouseExited(MouseEvent e) {
                // TODO Auto-generated method stub

            }
        });

        pathPlace.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {

                repaintingTree(pathPlace, tree, model, pathPlace.getText());

            }
        });

        setLayout(new BorderLayout());
        add(scrollPane);
        add(pathPlace,BorderLayout.NORTH);
    }

    public static void repaintingTree(JTextField pathPlace, JTree tree, TreeConstructor model){
        File place = new File(tree.getLastSelectedPathComponent().toString());
        if(place.isDirectory()) {
            pathPlace.setText(tree.getLastSelectedPathComponent().toString());
            model = new TreeConstructor(place);
            tree.setModel(model);
            tree.repaint();
    }}

    public static void repaintingTree(JTextField pathPlace, JTree tree, TreeConstructor model, String path){
        File place = new File(path);
        if(place.isDirectory()) {
            pathPlace.setText(path);
            model = new TreeConstructor(place);
            tree.setModel(model);
            tree.repaint();
            }
        else {
            JOptionPane.showMessageDialog(null, "Wrong directory");
        }
    }

这是我使用 JTree 的代码 我可以使用您的代码来渲染吗？ 我不明白：/