Question

我有2个窗口。一个得到一个空的JList，另一个得到一个按钮。因此，每当我按下按钮时，我都希望将值添加到列表中。这是我的代码，但没有完成：

窗口1

final DefaultListModel<String> favouriteNames = new DefaultListModel<String>();
JList namesList = new JList(favouriteNames);

窗口2

public class button extends JFrame {

private JList namesList;
private DefaultListModel<String> favouriteNames;

this.namesList = namesList;

 JButton addThis = new JButton("Add");
 addThis.addActionListener(new ActionListener(){
   public void actionPerformed(ActionEvent e) {
          favouriteNames.addElement("Jack");
   }
 });
}
}

Answer 1

在构造函数中将DefaultListModel的实例传递给Window 2.

编辑添加：以下是在构造函数中传递实例的方法。

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.SwingUtilities;

public class ButtonFrame implements Runnable {

    private JFrame              frame;

    private DefaultListModel    favouriteNames;

    public ButtonFrame(final DefaultListModel favouriteNames) {
        this.favouriteNames = favouriteNames;
    }

    @Override
    public void run() {
        frame = new JFrame();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        JButton addThis = new JButton("Add");
        addThis.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                favouriteNames.addElement("Jack");
            }
        });

        frame.add(addThis);
        frame.pack();
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new ButtonFrame(new DefaultListModel()));
    }

}

Answer 2

我制作了一个更简单的程序版本，但仍有问题，我相信ActionPerformed会发送数据，但JList无法识别它，或者基本上没想到会收到它。所以这就是我到目前为止所做的。所以这是我的研究和尝试的一点，也许它提供了有关问题的更多细节。

主窗口：

public class main {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        JFrame frame = new ClassA();
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);

    }

}

ClassA的：

public class ClassA extends JFrame {

        DefaultListModel<String> myList;
        JList list;

        public ClassA() {

        setSize(300,200);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new JPanel();
        panel.setLayout(new GridLayout(2,1));

        myList = new DefaultListModel<String>();
        list = new JList(myList);


        //ClassB sendsText = new ClassB(myList, list);

        JButton find = new JButton("Find");
        find.addActionListener(new ActionListener(){

            public void actionPerformed(ActionEvent e) {
                new ClassB().setVisible(true);
            }

        });


        add(panel);
        panel.add(find);
        panel.add(list);
    }

}

ClassB的：

public class ClassB extends JFrame {

    DefaultListModel<String> myList;
    JList list;
    public ClassB(DefaultListModel<String> myList, JList list){
        this.myList = myList;
        this.list = list;
    }


    public ClassB() {
        setSize(300,200);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JPanel panel = new JPanel();
        panel.setLayout(new GridLayout(2,1));

        JButton addMe = new JButton("Add Me");
        addMe.addActionListener(new ActionListener(){

            public void actionPerformed(ActionEvent e) {
                myList.addElement("Danial");

            }

        });

        add(panel);
        panel.add(addMe);
    }

}

如何从另一个窗口向JList添加项目

2 个答案: