Question

我的项目包含两部分：逻辑模块和gui界面。两者都将其引用发送给其他人。

当用户发送消息时，我有一个Key Listener。在这个监听器中，我在逻辑之前调用相同的gui更改，在逻辑之后调用相同的更改问题是两个更改都会在执行结束时同时显示。

如何实时强制进行GUI更新？

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Main {

    // Init DecisionEngine and GUIApplication
    private static final Logic _logic = new Logic();
    private static final GUI _gui = new GUI();

    public static void main(String[] args) {
        // Set DecisionEngine reference in GUIApplication and viceversa
        _gui.setLogicReference(_logic);
        _logic.setGUIRefecence(_gui);

        // User send a message
        _gui.textInput.addKeyListener(new KeyListener(){
            @Override public void keyPressed(KeyEvent e){
                if (e.getKeyCode() == KeyEvent.VK_ENTER) {

                    _gui.somethingChaged1();// CHANGE 1 GUI
                    _logic.thinking();// LOGIC PROCESSING (3sec)
                    _gui.somethingChaged2();// CHANGE 2 GUI

                    e.consume();// Stopping adding an Enter after message
                }
            }
            @Override public void keyTyped(KeyEvent e) {}
            @Override public void keyReleased(KeyEvent e) {}
        });
    }

    private static class Logic {
        GUI gui_ref;

        public Logic() {}
        private void setGUIRefecence(GUI _gui) {gui_ref = _gui;}
        private void thinking() {
            try {Thread.sleep(3000);} catch (InterruptedException ex) {}
        }
    }

    private static class GUI {

        Logic logic_ref;
        private JFrame frame;
        public  JTextArea textInput;
        private JLabel isTyping;

        public GUI() {

            frame = new JFrame();
            textInput = new javax.swing.JTextArea(5, 20);
            isTyping = new JLabel("Normal mode");

            frame.setSize(new Dimension(200,300));
            frame.add(textInput, BorderLayout.PAGE_START);
            frame.add(isTyping, BorderLayout.CENTER);
            frame.revalidate();
            frame.repaint();
            frame.setVisible(true);
        }

        private void setLogicReference(Logic _logic) {logic_ref = _logic;}
        private void somethingChaged1() {isTyping.setText("loading...");System.out.println("status changed in 'loading...'");}
        private void somethingChaged2() {isTyping.setText("is done.");System.out.println("status changed in 'is done.'");}
    }

}

Answer 1

为了澄清我在markbernard's answer中所做的评论，这是应该如何做的：

    @Override public void keyPressed(KeyEvent e){
        if (e.getKeyCode() == KeyEvent.VK_ENTER) {
            // Change the GUI from the EDT (current thread):
            _gui.somethingChaged1();

            // start a new Thread to do the long processing:
            Thread t = new Thread(new Runnable() {
              public void run() {
                _logic.thinking();// LOGIC PROCESSING (3sec)

                // when the processing in this new Thread is complete,
                // update the GUI again via the EDT:
                SwingUtilities.invokeLater(new Runnable(){
                  public void run() {
                    _gui.somethingChaged2();
                  }
                });
              }
            }, "Logic Code");
            t.start();

            e.consume();// Stopping adding an Enter after message
        }
    }

Answer 2

你的问题就在这里：

        @Override public void keyPressed(KeyEvent e){
            if (e.getKeyCode() == KeyEvent.VK_ENTER) {

                _gui.somethingChaged1();// CHANGE 1 GUI
                _logic.thinking();// LOGIC PROCESSING (3sec)
                _gui.somethingChaged2();// CHANGE 2 GUI

                e.consume();// Stopping adding an Enter after message
            }
        }

您正在事件派发线程中执行长时间运行的功能。 GUI在事件调度线程中更新，因此在您退出侦听器之前，不会看到GUI更改。试试这个：

        @Override public void keyPressed(KeyEvent e){
            if (e.getKeyCode() == KeyEvent.VK_ENTER) {
                Thread t = new Thread(new Runnable() {
                  _gui.somethingChaged1();// CHANGE 1 GUI
                  public void run() {
                    _logic.thinking();// LOGIC PROCESSING (3sec)
                    //Changed based on comment from daiscog
                    SwingUtilities.invokeLater(new Runnable() {
                      public void run() {
                        _gui.somethingChaged2();// CHANGE 2 GUI
                      }
                    });
                  }
                }, "Logic Code");
                t.start();

                e.consume();// Stopping adding an Enter after message
            }
        }

为线程命名也是一个很好的做法，所以如果你必须调试，你可以很容易地找到你创建的线程。

JFrame不会实时更新

2 个答案: