從一個jlist添加到另一個

Question

我一直在這里進行研究，並一直在尋找解決問題的方法。 我是Java的新手，所以我不了解所有語法。 我正在嘗試讓我的代碼使用jlist之間的按鈕將項目從一個jlist轉移到另一個jlist。 左側列表中包含開始的項目。 該代碼假定使用“添加”按鈕將項目從左側列表移至右側列表。 還假設使用“刪除”按鈕將添加到右側列表的所有項目移回左側列表。 我的代碼將項目從左側列表添加到右側列表，但不保存添加的項目。 我嘗試添加的下一項將替換舊項。 有人可以幫我嗎？ 以下是整個代碼。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.ListSelectionModel;

public class Window {

    private JFrame frame;

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    Window window = new Window();
                    window.frame.setVisible(true);
                }
                catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    public Window() {
        frame = new JFrame();
        frame.setBounds(100, 100, 450, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().setLayout(null);

        initialize();
    }

    public void initialize() {
        //Creating the Panel for Menu Bar       
        JPanel panel = new JPanel();
        panel.setBounds(0, 0, 434, 23);
        frame.getContentPane().add(panel);
        panel.setLayout(new BorderLayout(0, 0));
        //Creating the Menu File Bar
        JMenuBar bar = new JMenuBar();
        panel.add(bar, BorderLayout.NORTH);
        JMenu file = new JMenu("File");
        JMenuItem load = new JMenuItem("Load");
        JMenuItem save = new JMenuItem("Save");
        JMenuItem exit = new JMenuItem("Exit");
        file.add(load);
        file.add(save);
        file.add(exit);
        bar.add(file);

        //Populate Left List with part names    
        final DefaultListModel parts = new DefaultListModel();
        parts.addElement("Case");
        parts.addElement("Motherboard");
        parts.addElement("CPU");
        parts.addElement("GPU");
        parts.addElement("PSU");
        parts.addElement("RAM");
        parts.addElement("HDD");

        final JList leftList = new JList(parts);
        leftList.setBounds(10, 26, 142, 224);
        frame.getContentPane().add(leftList);

        //create right list 
        final DefaultListModel partSelected = new DefaultListModel();
        final JList rightList = new JList();
        rightList.setBounds(282, 26, 142, 224);
        frame.getContentPane().add(rightList);

        //add event to the button to move items from left list to right list
        JButton btnNewButton = new JButton(">>");
        btnNewButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {

                rightList.setListData(leftList.getSelectedValues());
                for (Object selectedValue : leftList.getSelectedValuesList()) {
                    partSelected.addElement(selectedValue);
                    parts.removeElement(selectedValue);
                    int iSelected = leftList.getSelectedIndex();
                    if (iSelected == -1) {
                        return;
                    }
                }
            }
        });
        btnNewButton.setBounds(172, 86, 89, 23);
        frame.getContentPane().add(btnNewButton);

        //Remove Button     
        JButton remove = new JButton("<<");
        remove.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {

                rightList.setListData(leftList.getSelectedValues());
                for (Object selectedValue : rightList.getSelectedValuesList()) {
                    parts.addElement(selectedValue);
                    int selected = rightList.getSelectedIndex();
                    if (selected == -1) {
                        return;
                    }
                    partSelected.removeElement(selectedValue);
                }
            }
        });
        remove.setBounds(172, 140, 89, 23);
        frame.getContentPane().add(remove);
    }
}

Answer 1

@ Prob1em我已經更新了您的代碼。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;

public class Window {

    private final JFrame frame;

    public static void main(String[] args) {
        EventQueue.invokeLater(() -> {
            Window window = new Window();
            window.frame.setVisible(true);

        });
    }

    public Window() {
        frame = new JFrame();
        frame.setBounds(100, 100, 450, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().setLayout(null);

        initialize();
    }

    public void initialize() {
        //Creating the Panel for Menu Bar       
        JPanel panel = new JPanel();
        panel.setBounds(0, 0, 434, 23);
        frame.getContentPane().add(panel);
        panel.setLayout(new BorderLayout(0, 0));
        //Creating the Menu File Bar
        JMenuBar bar = new JMenuBar();
        panel.add(bar, BorderLayout.NORTH);
        JMenu file = new JMenu("File");
        JMenuItem load = new JMenuItem("Load");
        JMenuItem save = new JMenuItem("Save");
        JMenuItem exit = new JMenuItem("Exit");
        file.add(load);
        file.add(save);
        file.add(exit);
        bar.add(file);

        //Populate Left List with part names    
        final DefaultListModel parts = new DefaultListModel();
        parts.addElement("Case");
        parts.addElement("Motherboard");
        parts.addElement("CPU");
        parts.addElement("GPU");
        parts.addElement("PSU");
        parts.addElement("RAM");
        parts.addElement("HDD");

        final JList leftList = new JList(parts);
        leftList.setBounds(10, 26, 142, 224);
        frame.getContentPane().add(leftList);

        //create right list 
        final DefaultListModel partSelected = new DefaultListModel();
        final JList rightList = new JList(partSelected);
        rightList.setBounds(282, 26, 142, 224);
        frame.getContentPane().add(rightList);

        //add event to the button to move items from left list to right list
        JButton btnNewButton = new JButton(">>");
        btnNewButton.addActionListener((ActionEvent arg0) -> {
//            rightList.setListData((Vector) leftList.getSelectedValue());
            for (Object selectedValue : leftList.getSelectedValuesList()) {
                partSelected.addElement(selectedValue);
                parts.removeElement(selectedValue);
                int iSelected = leftList.getSelectedIndex();
                if (iSelected == -1) {
                    return;
                }
            }
        });
        btnNewButton.setBounds(172, 86, 89, 23);
        frame.getContentPane().add(btnNewButton);

        //Remove Button     
        JButton remove = new JButton("<<");
        remove.addActionListener((ActionEvent arg0) -> {
//            rightList.setListData(leftList.getSelectedValues());
            for (Object selectedValue : rightList.getSelectedValuesList()) {
                parts.addElement(selectedValue);
                partSelected.removeElement(selectedValue);
                int selected = rightList.getSelectedIndex();
                if (selected == -1) {
                    return;
                }
            }
        });
        remove.setBounds(172, 140, 89, 23);
        frame.getContentPane().add(remove);
    }
}

順便說一句，為什么您要編寫rightList.setListData(leftList.getSelectedValues())及其在Java 8中也不推薦使用的方法，請遵循正確的命名約定，同時聲明變量，盡管我沒有在代碼中對其進行更改，但事件處理函數與Java 8 Lambda表達式 ，
希望這可以幫助