我有一个可编辑的秋天树，我想保存并加载这里是我的代码
public class Muddassir extends Application
{
private BorderPane root;
TreeView<String> tree;
TreeItem<String> module,unite,translateA ,translateB,rotate;
@Override
public void start(Stage primaryStage) throws Exception
{
root = new BorderPane();
root.setLeft(getLeftHBox());
root.setTop(getTop());
Scene scene = new Scene(root, 900, 500);
primaryStage.setTitle("BorderPane");
primaryStage.setScene(scene);
primaryStage.show();
}
private VBox getLeftHBox()
{
TreeItem<String> rootnode = new TreeItem<String>("Library");
rootnode.setExpanded(true);
module = makeBranch("module",rootnode);
makeBranch("Parameter X",module);
unite = makeBranch("unite",module);
makeBranch("Parameter uX",unite);
translateA = makeBranch("translateA",unite);
makeBranch("Parameter taX",translateA);
translateB = makeBranch("translateB",unite);
makeBranch("Parameter tbX",translateB);
rotate = makeBranch("rotate",translateB);
makeBranch("Parameter RX",rotate);
tree= new TreeView<>(rootnode);
tree.setEditable(true);
tree.setCellFactory(TextFieldTreeCell.forTreeView());
VBox vbox =new VBox(10);
vbox.setPadding(new Insets(5));
Text text= new Text("Fall tree");
text.setFont(Font.font("I", FontWeight.BOLD,16));
vbox.getChildren().addAll(text,tree);
return vbox;
}
private TreeItem<String> makeBranch(String title, TreeItem<String> parent) {
TreeItem<String>item = new TreeItem<>(title);
item.setExpanded(true);
parent.getChildren().add(item);
return item;
}
private Parent getTop() {
TextField fieldName = new TextField();
Button btSave = new Button("Save");
btSave.setOnAction(event -> {
SaveData data = new SaveData();
// data.name = ((TreeView<String>) tree).getText();
data.name = fieldName.getText();
try {
Function.save(data, "Javafx.save");
}
catch (Exception e) {
e.printStackTrace();
}
});
Button btLoad = new Button("Load");
btLoad.setOnAction(event -> {
try {
SaveData data = (SaveData) Function.load("Javafx.save");
//((TreeItems<String>)tree).setText(data.name);
fieldName.setText(data.name);
}
catch (Exception e) {
e.printStackTrace();
}
});
HBox hb= new HBox(5,fieldName,btSave,btLoad);
hb.setPadding(new Insets(5));
return hb;
}
public static void main(String[] args)
{
Application.launch(args);
}
}
功能类是
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.nio.file.Files;
import java.nio.file.Paths;
public class Function {
public static void save(Serializable data, String fileName) throws Exception {
try (ObjectOutputStream oos = new ObjectOutputStream(Files.newOutputStream(Paths.get(fileName)))) {
oos.writeObject(data);
}
}
public static Object load(String fileName) throws Exception {
try (ObjectInputStream ois = new ObjectInputStream(Files.newInputStream(Paths.get(fileName)))) {
return ois.readObject();
}
}
}
SaveData Class是
import javafx.scene.control.TreeView;
public class SaveData implements java.io.Serializable{
private static final long serialVersionUID = 1L;
public String name;
}
我想编辑树并进行更改，保存更改，下次执行后，我应该更改结果。由于我不太了解数据库所以我想出了这个方法来保存文件中的更改并加载该文件。
问题是我可以在文本字段中保存和加载文本，但我无法在树中保存和加载更改。
我想保存树中的更改，并在下次执行时加载这些更改。我试过但失败了。任何提示都没问题。
谢谢。
答案 0 :(得分：1)
您可以使用我刚创建的这款应用。它可以帮助您提出更好的解决方案。这个应用程序只处理两个深（见下文）或更少的树。您可以使其递归以使其处理任何深度。用于保存树的递归算法可以保存任何深度的树。非递归的loadTree方法只能处理2的深度。
-root depth-0
-child 1 depth-1
-child 1a depth-2
-child 2 depth-1
-child 3 depth-1
-child 3a depth-2
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TreeItem;
import javafx.scene.control.TreeView;
import javafx.scene.control.cell.TextFieldTreeCell;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
/**
*
* @author blj0011
*/
public class JavaFXApplication94 extends Application
{
@Override
public void start(Stage primaryStage)
{
TreeItem<String> treeRoot = new TreeItem("Node 0");
TreeItem<String> item1 = new TreeItem("Node 1");
TreeItem<String> item1Child = new TreeItem("Node 1a");
item1.getChildren().add(item1Child);
TreeItem<String> item2 = new TreeItem("Node 2");
TreeItem<String> item2Child = new TreeItem("Node 2a");
item2.getChildren().add(item2Child);
TreeItem<String> item3 = new TreeItem("Node 3");
treeRoot.setExpanded(true);
treeRoot.getChildren().addAll(item1, item2, item3);
TreeView<String> treeView = new TreeView(treeRoot);
treeView.setEditable(true);
treeView.setCellFactory(TextFieldTreeCell.forTreeView());
Button btn = new Button("Save TreeView");
btn.setOnAction(new EventHandler<ActionEvent>()
{
@Override
public void handle(ActionEvent event)
{
//If the file exist delete it and save new info
File file = new File("tree_structure.txt");
if(file.exists()) {
file.delete();
}
saveParentAndChildren(treeRoot, "root");
}
});
Button btn2 = new Button("Load TreeView");
btn2.setOnAction(new EventHandler<ActionEvent>()
{
@Override
public void handle(ActionEvent event)
{
//Load the tree structure into the old treeView
treeView.setRoot(loadTree());
}
});
StackPane root = new StackPane();
VBox vbox = new VBox();
vbox.getChildren().add(treeView);
vbox.getChildren().add(btn);
vbox.getChildren().add(btn2);
root.getChildren().add(vbox);
Scene scene = new Scene(root, 300, 250);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* @param args the command line arguments
*/
public static void main(String[] args)
{
launch(args);
}
static private void saveParentAndChildren(TreeItem<String> root, String parent){
System.out.println("Current Parent :" + root.getValue());
try(PrintWriter writer = new PrintWriter(new FileOutputStream(new File("tree_structure.txt"),true /* append = true */))){
writer.println(root.getValue() + "=" + parent);
for(TreeItem<String> child: root.getChildren()){
if(child.getChildren().isEmpty()){
writer.println(child.getValue() + "=" + root.getValue());
} else {
saveParentAndChildren(child, root.getValue());
}
}
}
catch (FileNotFoundException ex) {
Logger.getLogger(JavaFXApplication94.class.getName()).log(Level.SEVERE, null, ex);
}
}
static private TreeItem loadTree(){
TreeItem root = null;
HashMap<String, String> treeStructure = new HashMap();
File file = new File("tree_structure.txt");
try(BufferedReader br = new BufferedReader(new FileReader(file)))
{
String st;
while((st=br.readLine()) != null){
String[] splitLine = st.split("=");
treeStructure.put(splitLine[0], splitLine[1]);
}
root = getChildrenNodes(treeStructure, "root").get(0);//This gets the root node
List<TreeItem> parentItems = getChildrenNodes(treeStructure, root.getValue().toString());//get the root's children
//if the root has children get every child's children if they have some.
if(parentItems.size() > 0)
{
root.getChildren().addAll(parentItems);
for(TreeItem item : parentItems)
{
item.getChildren().addAll(getChildrenNodes(treeStructure, item.getValue().toString()));
}
}
}
catch (IOException ex) {
Logger.getLogger(JavaFXApplication94.class.getName()).log(Level.SEVERE, null, ex);
}
return root;
}
static private List<TreeItem> getChildrenNodes(HashMap<String, String> hMap, String parent)
{
List<TreeItem> children = new ArrayList();
for (Map.Entry<String, String> entry : hMap.entrySet())
{
if(entry.getValue().equals(parent))
{
System.out.println(entry.getKey() + "/" + entry.getValue());
children.add(new TreeItem(entry.getKey()));
}
}
return children;
}
}