在Java Swing中，我有两个节点和一个TreePath。 一个节点包含“根”节点（我们称其为nodeA），它包含其下的所有内容。 第二个节点是“新”节点（我们称其为nodeB），它包含一个新节点。 我有一个TreePath，显示我要在nodeA中插入nodeB的位置。我正在尝试开发一个功能来做到这一点。有什么帮助吗？ 预先感谢！
Node A
~
Documents
-- text1.txt
-- text2.txt
Pictures
- text1.txt
我想将下面的节点插入“图片”文件夹
folder1
-- newtext1.txt
我的insertNodes函数：
private static void insertNodes
(DefaultMutableTreeNode root
,DefaultMutableTreeNode newNode
,String tp)
{
String[] elements = tp.split("/");
String treePath = "";
for (int i=0; i<elements.length-1; i++)
{
if (i == elements.length-2)
{
treePath += elements[i];
} else {
treePath += elements[i] + "/" ;
}
}
System.out.println("TreePath : " + treePath);
DefaultMutableTreeNode node = buildNodeFromString(treePath);
DefaultMutableTreeNode lastLeaf = node.getLastLeaf();
TreePath path = new TreePath(lastLeaf.getPath());
System.out.println("insertNodes-Path =" + path);
DefaultTreeModel model = new DefaultTreeModel(root);
DefaultMutableTreeNode pictureNode = (DefaultMutableTreeNode) path.getLastPathComponent();
pictureNode.add(newNode);
// Notify the model of the changes
model.nodesWereInserted(pictureNode, new int[]{pictureNode.getChildCount() - 1});
// The above way (you suggested) wipes out everything and just puts one "~" in the JTree
// The below line adds them all to the "~" direcotry
//root.add(newNode);
}
我的getFileStructure（在这里我称为insertNodes）
public static DefaultMutableTreeNode getFileStructure(FTPClient client,String workingPath,DefaultMutableTreeNode style )
{
try {
System.out.println("\n");
System.out.println("Working Path: " + workingPath);
FTPFile[] files = client.listFiles(workingPath);
DefaultMutableTreeNode node = buildNodeFromString(workingPath);
DefaultMutableTreeNode lastLeaf = node.getLastLeaf();
TreePath path = new TreePath(lastLeaf.getPath());
System.out.println("Path =" + path);
DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode)(path.getLastPathComponent());
System.out.println("Add to Node:" + selectedNode.toString());
for (FTPFile file : files) {
if (file.isDirectory())
{
// DefaultMutableTreeNode fileDirectory =new DefaultMutableTreeNode(file.getName());
// selectedNode.add(fileDirectory);
System.out.println("\t Folder Name: " + file.getName());
getFileStructure(client, workingPath + "/" + file.getName(),style);
} else {
DefaultMutableTreeNode root =new DefaultMutableTreeNode();
System.out.println("Filename: " + file.getName());
DefaultMutableTreeNode fileDirectory =new DefaultMutableTreeNode(file.getName());
selectedNode.add(fileDirectory);
System.out.println("Added to node = " + selectedNode.toString());
System.out.println("First Node = " + selectedNode.getFirstChild().toString());
System.out.println("Last Node = " + selectedNode.getLastChild().toString());
System.out.println("Num of Children = " + selectedNode.getLeafCount());
System.out.println("Depth Count= " + selectedNode.getDepth());
}
}
insertNodes(style,selectedNode,workingPath);
} catch (IOException ex) {
System.out.println("IOException:" + ex);
}
return style;
}
答案 0 :(得分：1)
好的，假设一些，假设您有一个TreeModel，看起来像这样……
DefaultMutableTreeNode root = new DefaultMutableTreeNode("~");
DefaultTreeModel model = new DefaultTreeModel(root);
DefaultMutableTreeNode docs = new DefaultMutableTreeNode("Documents");
docs.add(new DefaultMutableTreeNode("text1.txt"));
docs.add(new DefaultMutableTreeNode("text2.txt"));
root.add(docs);
DefaultMutableTreeNode pics = new DefaultMutableTreeNode("Pictures");
pics.add(new DefaultMutableTreeNode("text1.txt"));
root.add(pics);
这将生成一棵看起来像...的树
+ ~
+ Documents
- text1.txt
- text2.txt
+ Pictures
- text1.txt
然后，假设您知道要添加...
DefaultMutableTreeNode newFolder = new DefaultMutableTreeNode("folder1");
newFolder.add(new DefaultMutableTreeNode("text1.txt"));
到~/Pictures。
假设您在TreePath上有一个有效的[~, Pictures]，则可以简单地从路径中获取lastComponent，该路径将引用Pictures {{1} }，那么您可以简单地做类似...
TreeNode这将生成像...的树
DefaultMutableTreeNode pictureNode = (DefaultMutableTreeNode) treePathFromPicturesToRoot.getLastPathComponent();
pictureNode.add(newFolder);
// Notify the model of the changes
model.nodesWereInserted(pictureNode, new int[]{pictureNode.getChildCount() - 1});
现在，我不知道您+ ~
+ Documents
- text1.txt
- text2.txt
+ Pictures
- text1.txt
+ folder1
- text1.txt
的来源，但我认为这是由TreePath中实际存在的节点组成的有效路径，否则它将无法正常工作很好
现在，基于许多示例，如果这不能满足您的需求，那么您将需要提供Minimal, Complete, and Verifiable example，以便我们更好地了解您的问题
我使用以下代码构建了基本概念
TreeModel您的插入方法应该和...一样简单
import java.util.Enumeration;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;
public class Test {
public static void main(String[] args) {
DefaultMutableTreeNode root = new DefaultMutableTreeNode("~");
DefaultTreeModel model = new DefaultTreeModel(root);
DefaultMutableTreeNode docs = new DefaultMutableTreeNode("Documents");
docs.add(new DefaultMutableTreeNode("text1.txt"));
docs.add(new DefaultMutableTreeNode("text2.txt"));
root.add(docs);
DefaultMutableTreeNode pics = new DefaultMutableTreeNode("Pictures");
pics.add(new DefaultMutableTreeNode("text1.txt"));
root.add(pics);
describe(model);
DefaultMutableTreeNode newFolder = new DefaultMutableTreeNode("folder1");
newFolder.add(new DefaultMutableTreeNode("text1.txt"));
TreeNode[] pathToRoot = pics.getPath();
TreePath treePathFromPicturesToRoot = new TreePath(pathToRoot);
System.out.println(treePathFromPicturesToRoot);
DefaultMutableTreeNode pictureNode = (DefaultMutableTreeNode) treePathFromPicturesToRoot.getLastPathComponent();
pictureNode.add(newFolder);
model.nodesWereInserted(pictureNode, new int[]{pictureNode.getChildCount() - 1});
describe(model);
}
protected static void describe(DefaultTreeModel model) {
describe((DefaultMutableTreeNode) model.getRoot(), 0);
}
protected static void describe(DefaultMutableTreeNode node, int level) {
StringBuilder padding = new StringBuilder();
for (int index = 0; index < level; index++) {
padding.append(" ");
}
System.out.println(padding + "+ " + node);
padding.append(" ");
Enumeration<TreeNode> children = node.children();
while (children.hasMoreElements()) {
DefaultMutableTreeNode childNode = (DefaultMutableTreeNode) children.nextElement();
if (childNode.isLeaf()) {
System.out.println(padding + "- " + childNode);
} else {
describe(childNode, level + 1);
}
}
}
}
要基于private static void insertNodes(
DefaultTreeModel model,
DefaultMutableTreeNode parent,
DefaultMutableTreeNode newNode) {
parent.add(newNode);
model.nodesWereInserted(parent, new int[]{parent.getChildCount() - 1});
}
路径查找节点，您可以“执行” ...
String这意味着，根据我之前的示例，您可以执行以下操作...
protected static DefaultMutableTreeNode findNode(DefaultTreeModel model, String path) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) model.getRoot();
String[] parts = path.split("/");
if (node.getUserObject().toString().equals(parts[0])) {
return findNode(node, Arrays.copyOfRange(parts, 1, parts.length));
}
return null;
}
protected static DefaultMutableTreeNode findNode(DefaultMutableTreeNode node, String[] path) {
if (path.length == 0) {
return node;
}
Enumeration<TreeNode> children = node.children();
while (children.hasMoreElements()) {
DefaultMutableTreeNode child = (DefaultMutableTreeNode)children.nextElement();
if (child.getUserObject().toString().equals(path[0])) {
return findNode(node, Arrays.copyOfRange(path, 1, path.length));
}
}
return null;
}
DefaultMutableTreeNode newFolder = new DefaultMutableTreeNode("folder1");
newFolder.add(new DefaultMutableTreeNode("text1.txt"));
insertNodes(model, findNode(model, "~/Pictures"), newFolder);