JavaFX-向父节点添加节点时的奇怪行为

Question

我创建了一个简单的应用程序来模拟JAVAFX的动态节点创建。这个应用程序能够通过单击“新建”按钮在用户需要的时候创建一个新窗口。用户可以通过单击“添加任务”按钮，然后单击对话框窗口上的“添加”按钮，将标题窗格的新节点添加到窗口中。

我想修复一个意外行为。此应用程序仅将新节点（在本例中为TitledPane）添加到最后创建的窗口。并且上一个窗口上的所有节点都将消失。

你可以看下面的视频来更好地理解我的意思。

视频

https://youtu.be/eaWmu3zuuhE

NETBEANS项目

以防你想玩它。

https://drive.google.com/file/d/0B4Sbb8Ym-lcZLUIyWHV5ZXRSZE0/view?usp=sharing

代码：

任务列表。Java语言

package taskslist;


import javafx.application.Application;
import javafx.scene.Parent;
import javafx.stage.Stage;

public class TasksList extends Application {

    DisplayWhich display = new DisplayWhich();
    Stage primaryStage;
    Parent startWindow;

    @Override
    public void start(Stage primaryStage) throws Exception {
        this.primaryStage = primaryStage;
        initStart();
    }

    private void initStart(){  
             display.showDialogWindow();
    }   

    public static void main(String[] args) {
        launch(args);
    }

}

列表。Java语言

package taskslist.view;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ScrollPane;
import javafx.scene.control.TextField;
import javafx.scene.control.TitledPane;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.HBox;
import javafx.scene.layout.VBox;
import javafx.stage.Modality;
import javafx.stage.Stage;
import taskslist.DisplayWhich;

public class TheList extends BorderPane {
    public static VBox listWrapper;
    public static ScrollPane listScroller;
    public ObservableList<TitledPane> tasks;
    private List<String> titles = new ArrayList<>();

    public TheList(){
        tasks = FXCollections.observableArrayList();
        listWrapper = new VBox(5);
        listScroller = new ScrollPane(listWrapper);  
    }

    public void setTitles(String... title){
        titles = Arrays.asList(title);
    }

    public List<String> getTitles(){
        return titles;
    }

    public void loadSavedList(){                                                  
        for(int i=0; i<getTitles().size();i++){ 
            String ttlString = getTitles().get(i);
            this.createTask(ttlString);            
        }        
        // Display Tasks
        listWrapper.getChildren().addAll(this.tasks);
    }

    // Dialong for adding a new task and also editing a task
    private void addTaskDialog(){        
        GridPane container = new GridPane();
        Scene scene = new Scene(container, 150, 50);
        Stage addNewTask = new Stage();
        addNewTask.initModality(Modality.APPLICATION_MODAL);
        addNewTask.setTitle("Add Task");  

        TextField title = new TextField();                                                                                        

        Button confirm = new Button("Add");                                                      

        // Create Task
        confirm.setOnAction((ev) -> {
            String ttlString = title.getText();                   
            this.createTask(ttlString);             
            listWrapper.getChildren().clear();
            listWrapper.getChildren().addAll(this.tasks);           
            addNewTask.close();                     
        }); 

        container.add(title, 0, 1);       
        container.add(confirm, 0, 5);  

        addNewTask.setScene(scene);
        addNewTask.showAndWait();
    }


    // Assemble all this.tasks list components
    public void render(){       
        setCenter(listScroller);
        loadSavedList();
        Button newProject = new Button("New");                                                                    
        Button addTask = new Button("Add Task");

        BorderPane listBottom = new BorderPane();
        HBox bottomLeft = new HBox();
        bottomLeft.getChildren().add(newProject);
        listBottom.setLeft(bottomLeft);                
        HBox bottomRight = new HBox();
        bottomRight.getChildren().add(addTask);
        listBottom.setRight(bottomRight);  

        newProject.setOnAction((evt) -> {
            DisplayWhich display = new DisplayWhich();
            display.showDialogWindow();
        });

        addTask.setOnAction((e) -> {
            addTaskDialog();
        });    

        setBottom(listBottom);
    }

    // Cteate task from strings
    private void createTask(String... strings){
        String taskTitle = strings.length > 0 ? strings[0] : "";
        TitledPane task = new TitledPane();
        task.setPrefWidth(647);
        task.setExpanded(false);
        task.setText(taskTitle);        
        this.tasks.add(task);            
    }    
}

NewDialog.java

package taskslist.view;

import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.Parent;
import javafx.scene.control.Button;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Stage;
import taskslist.DisplayWhich;

public class NewDialog {
    DisplayWhich display = new DisplayWhich();
    Stage stage = new Stage();
    Parent startWindow = new AnchorPane();

    @FXML
    private Button cancelNew;
    @FXML
    private Button confirmCreation;
    /**
     * Initializes the controller class.
     */
    @FXML
    private void initialize() {
    }  

    @FXML
    private void cancelNewCreation(ActionEvent event) {
       ((Stage)cancelNew.getScene().getWindow()).close();
    }

    @FXML
    private void confirmCreateNew(ActionEvent event) {
        ((Stage)confirmCreation.getScene().getWindow()).close();        
        TheList wrap = new TheList();
        TheWindow window = new TheWindow();
        window.makeWindow(wrap); 
        wrap.setTitles("one", "two", "three", "four");
        wrap.render();
    }          
}

显示哪个。Java语言

package taskslist;

import java.io.IOException;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Modality;
import javafx.stage.Stage;
import taskslist.view.TheList;

public class DisplayWhich {
    Stage stage = new Stage();
    Parent startWindow = new AnchorPane(); 

    public DisplayWhich(){}

    public Stage showDialogWindow(){ 
        try {
            stage.initModality(Modality.APPLICATION_MODAL);
            stage.setTitle("Create New Project");
            FXMLLoader loader = new FXMLLoader();
            loader.setLocation(getClass().getResource("/taskslist/view/newDialog.fxml"));        
            startWindow = loader.load();            
            Scene scene = new Scene(startWindow);            
            stage.setScene(scene);
            stage.setOnCloseRequest((event) -> {
                System.out.println("test");
            });
            stage.showAndWait();
        } catch (IOException ex) {
            ex.printStackTrace();
        }   
        return stage;
    }
}

窗户。Java语言

package taskslist.view;

import javafx.scene.Scene;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;

public class TheWindow {
    public TheWindow(){}

    public void makeWindow(BorderPane group) {
        Stage mainWindow = new Stage();
        Scene scene = new Scene(group, 650, 550);
        mainWindow.setScene(scene);
        mainWindow.setTitle("Task List");
        mainWindow.centerOnScreen();        
        mainWindow.show();
    }    
}

为什么会发生这种奇怪的行为，以及如何修复它，使其仅将新节点添加到单击的“添加任务”按钮所在的同一窗口中？

Answer 1

这些字段不应是静态的：

public static VBox listWrapper;
public static ScrollPane listScroller;