我正在制作一个游戏客户端/服务器，并且我有一个新线程更新客户端 GUI（使用 Swing）上的一些信息。我正在尝试使用 SwingUtilities，但它不起作用。另外，我听说 SwingUtilities 每次使用它时都会创建一个新线程，所以我也在寻找一种新方法（我有 10 个左右的 JTextField 需要更新）。有没有办法在不使用 SwingUtilities 的情况下做到这一点？这是我现在所拥有的。
SwingUtilities.invokeLater(
new Runnable() {
public void run()
{
Client.status.setText("status = "+status);
}
});
有趣的是，就在最近我遇到了一个类似的问题，所以为了解决这个问题，我使用了SwingUtilities.invokeAndWait(Runnable runnable)，这就是使我创建的SSCCE按预期工作的原因，尽管如果我将所有调用更改为invokeAndWait()使用invokeLater()，可以清楚地看到两者之间的区别。
Java Doc 的引用说：
Causes doRun.run() to be executed synchronously on the AWT event dispatching thread.
This call blocks until all pending AWT events have been processed and
(then) doRun.run() returns. This method should be used when an application thread
needs to update the GUI.
这是我作为SSCCE制作的一个小程序，用于表示冒泡排序动画：
import javax.swing.*;
public class BubbleSortFrame extends JFrame
{
private BubbleSortView contentPane;
private void displayGUI()
{
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
contentPane = new BubbleSortView();
setContentPane(contentPane);
pack();
setLocationByPlatform(true);
setVisible(true);
}
public static void main(String... args)
{
SwingUtilities.invokeLater(new Runnable()
{
@Override
public void run()
{
new BubbleSortFrame().displayGUI();
}
});
}
}
import java.awt.*;
import java.awt.event.*;
import java.lang.reflect.InvocationTargetException;
import javax.swing.*;
public class BubbleSortView extends JPanel
{
private JLabel sizeLabel;
private JTextField sizeField;
private JTextField[] vField;
private JLabel[] vLabel;
private JButton startButton, createButton;
private int size;
private JPanel createPanel, animationPanel;
private BubbleSort bubbleSort;
public BubbleSortView()
{
size = 5;
displayAndCreateGUI();
}
private void displayAndCreateGUI()
{
setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
setOpaque(true);
setBackground(Color.WHITE);
JPanel basePanel = new JPanel();
basePanel.setLayout(new GridLayout(2, 1, 5, 5));
basePanel.setOpaque(true);
basePanel.setBackground(Color.WHITE);
JPanel topPanel = new JPanel();
topPanel.setOpaque(true);
topPanel.setBackground(Color.WHITE);
topPanel.setBorder(
BorderFactory.createTitledBorder("Input : "));
topPanel.setLayout(new GridLayout(2, 1, 5, 5));
/*
* This will act as the area
* for taking the input for
* number of elements in an Array.
*/
JPanel sizePanel = new JPanel();
sizePanel.setOpaque(true);
sizePanel.setBackground(Color.WHITE);
sizeLabel = new JLabel("Enter Number of Elements : ");
sizeField = new JTextField(10);
createButton = new JButton("CREATE");
/*
* This will act as the area
* where we will specify the values
* for each index in an Array.
*/
createPanel = new JPanel();
createPanel.setOpaque(true);
createPanel.setBackground(Color.WHITE);
createPanel.setBorder(
BorderFactory.createTitledBorder("Please Enter values for an Array : "));
createPanel.setVisible(false);
animationPanel = new JPanel();
animationPanel.setOpaque(true);
animationPanel.setBackground(Color.WHITE);
animationPanel.setBorder(
BorderFactory.createTitledBorder("Animation : "));
animationPanel.setVisible(false);
createButton.addActionListener(new ActionListener()
{
@Override
public void actionPerformed(ActionEvent ae)
{
if (sizeField.getDocument().getLength() > 0)
{
size = Integer.parseInt(sizeField.getText());
vField = new JTextField[size];
createPanel.setVisible(true);
for (int i = 0; i < size; i++)
{
vField[i] = new JTextField(5);
/*
* Adding the Listener to the
* last JTextField on the Right
* Side.
*/
if (i == (size - 1))
{
vField[i].addActionListener(new ActionListener()
{
@Override
public void actionPerformed(ActionEvent ae)
{
animationPanel.setLayout(
new GridLayout(1, size, 2, 2));
animationPanel.setVisible(true);
vLabel = new JLabel[size];
for (int i = 0; i < size; i++)
{
vLabel[i] = new JLabel(
vField[i].getText(), JLabel.CENTER);
vLabel[i].setOpaque(true);
vLabel[i].setBackground(Color.YELLOW);
vLabel[i].setForeground(Color.RED);
animationPanel.add(vLabel[i]);
}
animationPanel.revalidate();
animationPanel.repaint();
bubbleSort = new BubbleSort(vLabel, size);
Thread t = new Thread(bubbleSort);
t.start();
}
});
}
createPanel.add(vField[i]);
}
createPanel.revalidate();
createPanel.repaint();
createButton.setEnabled(false);
}
else
size = 5;
}
});
sizePanel.add(sizeLabel);
sizePanel.add(sizeField);
sizePanel.add(createButton);
/*
* Initializing JTextField Array
* so that it can be first presented
* to the USER to take input for
* 5 values.
*/
//for (int i = 0; i < size; i++)
// vField[i] = new JTextField(5);
topPanel.add(sizePanel);
topPanel.add(createPanel);
basePanel.add(topPanel);
basePanel.add(animationPanel);
add(basePanel);
}
private class BubbleSort implements Runnable
{
private int[] arr;
private JLabel[] vLabel;
private int size;
private int pass;
public BubbleSort(JLabel[] label, int size)
{
vLabel = label;
this.size = size;
pass = 1;
for (int i = 0; i < size; i++)
System.out.print("" + vLabel[i].getText() + "\t");
System.out.println("");
}
@Override
public void run()
{
try
{
bubbleSorting();
}
catch (InvocationTargetException ite)
{
ite.printStackTrace();
}
catch(InterruptedException ie)
{
ie.printStackTrace();
}
}
private void bubbleSorting()
throws InterruptedException, InvocationTargetException
{
while (pass < size)
{
for (int i = 0; i < (size - pass); i++)
{
final int j = i;
SwingUtilities.invokeAndWait(new Runnable()
{
@Override
public void run()
{
vLabel[j].setBackground(Color.RED);
vLabel[j].setForeground(Color.WHITE);
vLabel[j + 1].setBackground(Color.RED);
vLabel[j + 1].setForeground(Color.WHITE);
}
});
try
{
Thread.sleep(1500);
}
catch(InterruptedException ie)
{
ie.printStackTrace();
}
int left = Integer.parseInt(vLabel[i].getText());
int right = Integer.parseInt(vLabel[i + 1].getText());
if (left > right)
{
String temp = vLabel[i].getText();
vLabel[i].setText(vLabel[i + 1].getText());
vLabel[i + 1].setText(temp);
}
SwingUtilities.invokeAndWait(new Runnable()
{
@Override
public void run()
{
vLabel[j].setBackground(Color.YELLOW);
vLabel[j].setForeground(Color.RED);
vLabel[j + 1].setBackground(Color.YELLOW);
vLabel[j + 1].setForeground(Color.RED);
}
});
}
System.out.println("Pass : " + pass + "\tSize : " + size);
SwingUtilities.invokeAndWait(new Runnable()
{
@Override
public void run()
{
vLabel[size - pass].setBackground(Color.GREEN);
vLabel[size - pass].setForeground(Color.BLUE);
}
});
pass++;
}
SwingUtilities.invokeAndWait(new Runnable()
{
@Override
public void run()
{
vLabel[0].setBackground(Color.GREEN);
vLabel[0].setForeground(Color.BLUE);
}
});
}
}
}
我不知道您从哪里听说过“ SwingUtilities 创建一个新线程”，但我认为您要么误解了，要么被错误地告知。 SwingUtilities.invokeLater将Runnable放在事件调度程序队列的末尾。然后队列在它自己的线程上下文中（及时）处理这个事件，调用Run，没有为这个进程创建“新”线程。
至于你的问题。
您可能需要validate()（并且可能repaint()）调用字段父容器以鼓励它更新；）
不，没有任何其他方法可以跨线程同步 UI，这就是SwingUtilities