java - 增加另一个 JFrame 中存在的 JTextField 数量

Question

因此，如果我单击第一帧中存在的按钮，则另一个第二帧中存在的 JTextField 中的数字会增加。

第一帧包含 JButton，第二帧包含 JTextField。

请帮忙。

Answer 1

尝试下面的源代码:

import java.awt.Font;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.SwingWorker;

public class FirstFrame extends JFrame {
    private static final long serialVersionUID = 1L;

    private SecondFrame secondFrame;
    private boolean flag = new Boolean(false);
    private volatile Integer number;

    @SuppressWarnings("unused")
    private SwingWorker<Void, Void> swingWorker;

    public FirstFrame() {
        init();
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new FirstFrame();
            }
        });
    }

    private void init() {
        setTitle("First Frame");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        getContentPane().setLayout(new GridLayout(2, 1));
        setBounds(500, 300, 250, 110);

        final JButton increaseBtn = new JButton("Increase Number");
        final JButton start = new JButton("Start");
        final JButton stop = new JButton("Stop");

        stop.setEnabled(false);

        JPanel panel = new JPanel();

        increaseBtn.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent evt) {
                if (!flag) {
                    number = secondFrame.getNumber();
                    secondFrame.setNumber(number + 1);
                }
            }
        });

        start.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent evt) {
                flag = true;
                startContinuousIncreasing();
                start.setEnabled(false);
                stop.setEnabled(true);
                increaseBtn.setEnabled(false);
            }
        });

        stop.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent evt) {
                flag = false;
                stop.setEnabled(false);
                start.setEnabled(true);
                increaseBtn.setEnabled(true);
            }
        });

        getContentPane().add(increaseBtn);
        getContentPane().add(panel);

        panel.add(start);
        panel.add(stop);

        setVisible(true);
        secondFrame = SecondFrame.getSecondFrame();
        increaseBtn.requestFocus();
    }

    private void startContinuousIncreasing() {
        swingWorker = new SwingWorker<Void, Void>() {
            @Override
            protected Void doInBackground() throws Exception {
                while (flag) {
                    number = secondFrame.getNumber();
                    secondFrame.setNumber(number + 1);
                }
                return null;
            }
        };
        swingWorker.execute();
    }

}

class SecondFrame extends JFrame {
    private static final long serialVersionUID = 1L;

    private static Integer number;
    private JTextField textField;
    private static SecondFrame secondFrame;

    private SecondFrame() {
        init();
    }

    public synchronized static SecondFrame getSecondFrame() {
        if (secondFrame == null)
            secondFrame = new SecondFrame();
        return secondFrame;
    }

    private void init() {
        setTitle("Second Frame");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        getContentPane().setLayout(new GridLayout(1, 1));
        setBounds(500, 412, 250, 70);

        number = new Integer(0);

        textField = new JTextField(String.valueOf(number));
        textField.setFont(new Font("Dialog", Font.BOLD + Font.ITALIC, 22));
        getContentPane().add(textField);

        setVisible(true);
    }

    public synchronized Integer getNumber() {
        return number;
    }

    public synchronized void setNumber(Integer num) {
        try {
            number = num;
            this.textField.setText(String.valueOf(number));
        } catch (NumberFormatException nfe) {
            number = 0;
            this.textField.setText(String.valueOf(number));
        }
    }
}