更新 JFrame 并使用 Thread.sleep() [重复]
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【中文标题】更新 JFrame 并使用 Thread.sleep() [重复]【英文标题】：Updating JFrame and using Thread.sleep() [duplicate] 【发布时间】：2014-04-29 12:55:05 【问题描述】：我一直在努力解决一个我现在不太了解的奇怪问题（我对线程的了解很少）：
我有一个 JFrame 类，它应该使用 JButtons 来代表队列中的客户。有一个名为simulate() 的方法，本质上，每次调用它时都会向JFrame 添加一个新的JButton。我想在每次调用后重复调用该方法并短暂暂停。为此，我尝试了以下方法：
private void goButtonActionPerformed(java.awt.event.ActionEvent evt)
try
for(int i = 0; i < sim.length ; i++)
simulate();
Thread.sleep(500);
catch (Exception e)
但程序只是等到循环完成更新 JFrame（即，几秒钟后突然出现五个客户，而不是每半秒到达一个）。有什么问题？我是否导致错误的线程进入睡眠状态？我可以使用 wait() 吗？
完整的程序真的很长，但如果有帮助，我会在此处包含它：
package homeworkfour;
import java.awt.Color;
import java.awt.Component;
import java.util.ArrayList;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JButton;
import javax.swing.JTextField;
public class GUI extends javax.swing.JFrame
final private int w = 60, h = 20;
ArrayList<Integer> busy = new ArrayList<>();
ArrayList<Integer> linePositions;
ArrayList<Integer> kioskPositions;
public Simulator sim = new Simulator();
private boolean fastMode = false;
public GUI()
initComponents();
busy.add(-1);//BEFORE -1 IS BROKEN KIOSKS, AFTER IS FIXERS
this.getContentPane().setBackground(new Color(255,240,240));//reddish background? maybe
this.setVisible(false);
private void simulate(boolean fastMode) throws InterruptedException
ArrayList<Integer> feedback;
int spaces = (int)((double)(375 - (sim.num_cashiers * w))/(double)sim.num_cashiers);
int kspaces = (int)((double)(375 - (sim.num_kiosks * w))/(double)sim.num_kiosks);
feedback = sim.simulate();
if(feedback.get(0)!=0)//a customer spawned, add a button!!
JButton cButton = buildButton();
System.out.println(feedback.get(0));
boolean kiosk = feedback.get(0) < 0;//these
feedback.set(0, Math.abs(feedback.get(0)));//lines
int lineNumber = feedback.get(0)%100;//parse
int waitTime = feedback.get(0)/100;//feedback[0]
cButton.setText(String.valueOf(waitTime));
cButton.setVisible(true);
//System.out.println("cSpawn~");
if(!kiosk)
cButton.setBounds((spaces/2)+(lineNumber*(spaces+w)), linePositions.get(lineNumber), w, h);
linePositions.set(lineNumber, linePositions.get(lineNumber)+35);
else//they joined a kiosk
cButton.setBounds(375 + (kspaces/2)+(lineNumber*(kspaces+w)),kioskPositions.get(lineNumber),w,h);
kioskPositions.set(lineNumber,kioskPositions.get(lineNumber)+35);
this.add(cButton);
//System.out.println(cButton.getBounds().getLocation().toString());
if(feedback.get(1)!=0)//hey someone finished this turn!
sim.totalTimeWaited+=feedback.get(1);
//we will remove their button in another block(:
for (int i = 2,value = feedback.get(i); value != -1; i++, value = feedback.get(i)) //goes through all cashiers who lose a customer
remove(getComponentAt((spaces/2)+(value*(spaces+w)), 65));
reButton(i);
for (int i = feedback.indexOf(-1)+1, value = feedback.get(i); value!= -2; i++,value = feedback.get(i))//kiosks...
remove(getComponentAt(375 + (kspaces/2)+(value*(kspaces+w)),65));
reButton(-i);
for (int i = feedback.indexOf(-2)+1, value = feedback.get(i); value!=-3;i++,value = feedback.get(i))//goes through broken kiosks
busy.add(0,value);
getComponentAt(375+(kspaces/2)+(value*kspaces+w), 30).setBackground(Color.red);
for (int i = feedback.indexOf(-3)+1, value = feedback.get(i); value!=-4;i++,value = feedback.get(i))//goes through fixer dudes
busy.add(busy.indexOf(-1)+1,value);
getComponentAt((spaces/2)+(value*spaces+w), 30).setBackground(Color.red);
for (int i = 0; i < sim.num_cashiers; i++)
if(sim.cashiers[i].getRepairTime()==0)
getComponentAt((spaces/2)+(i*spaces+w), 30).setBackground(Color.black);
for (int i = 0; i < sim.num_kiosks; i++)
if(!sim.kiosks[i].broken)
getComponentAt((kspaces/2)+(i*kspaces+w), 30).setBackground(Color.black);
jLabel1.setText("Time = "+sim.time);
jLabel3.setText("Orders = "+sim.orders);
revalidate();
repaint();
Thread.sleep(300);
private void reButton(int line)
int y = 65;
int x;
Component c;
int spaces = (int)((double)(375 - (sim.num_cashiers * w))/(double)sim.num_cashiers);
int kspaces = (int)((double)(375 - (sim.num_kiosks * w))/(double)sim.num_kiosks);
if(line>0)//ITS A CASHIER LINE
x = ((spaces/2)+(line*(spaces+w)));
for(;getComponentAt(x,y)!=null;y+=35)
getComponentAt(x,y).setLocation(x, y-35);
else//ITS A KIOSK LINE
x = (375 + (kspaces/2)+(-line*(kspaces+w)));
for(;getComponentAt(x,y)!=null;y+=35)
getComponentAt(x,y).setLocation(x, y-35);
revalidate();
repaint();
private JButton buildButton()
JButton button = new JButton();
button.setContentAreaFilled(false);
button.setOpaque(true);
button.setBorderPainted(false);
button.setForeground(Color.black);
button.setBackground(Color.white);
button.setVisible(true);
return button;
public void buildLines()
JButton temp;
linePositions = new ArrayList<>(sim.num_cashiers);
kioskPositions = new ArrayList<>(sim.num_kiosks);
for (int i = 0; i < sim.num_cashiers; i++)
linePositions.add(65);
for (int i = 0; i < sim.num_kiosks; i++)
kioskPositions.add(65);
//System.out.println(linePositions.size());
for (int i = 0; i < sim.num_cashiers; i++) //sets up cashier buttons
temp = buildButton();
int spaces = (int)((double)(375 - (sim.num_cashiers * w))/(double)sim.num_cashiers);
temp.setBounds((spaces/2)+(i*(spaces+w)),30,w,h);
temp.setText("~C~");
temp.setBackground(Color.darkGray);
temp.setForeground(Color.white);
this.add(temp);
for (int i = 0; i < sim.num_kiosks; i++) //sets up cashier buttons
temp = buildButton();
int spaces = (int)((double)(375 - (sim.num_kiosks * w))/(double)sim.num_kiosks);
temp.setBounds((375+(spaces/2))+(i*(spaces+w)),30,w,h);
temp.setText("~K~");
temp.setBackground(Color.darkGray);
temp.setForeground(Color.white);
this.add(temp);
/**
* This method is called from within the constructor to initialize the form.
* WARNING: Do NOT modify this code. The content of this method is always
* regenerated by the Form Editor.
*/
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">
private void initComponents()
jPanel1 = new javax.swing.JPanel();
fastModeButton = new javax.swing.JToggleButton();
jButton1 = new javax.swing.JButton();
jLabel1 = new javax.swing.JLabel();
jLabel3 = new javax.swing.JLabel();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
setTitle("CSE214HW4");
setBackground(new java.awt.Color(255, 230, 230));
setPreferredSize(new java.awt.Dimension(750, 435));
jPanel1.setBackground(new java.awt.Color(230, 230, 255));
jPanel1.setMinimumSize(new java.awt.Dimension(100, 30));
fastModeButton.setText("Toggle Fast Mode");
fastModeButton.setMaximumSize(new java.awt.Dimension(140, 20));
fastModeButton.setMinimumSize(new java.awt.Dimension(140, 20));
fastModeButton.addActionListener(new java.awt.event.ActionListener()
public void actionPerformed(java.awt.event.ActionEvent evt)
fastModeButtonActionPerformed(evt);
);
jButton1.setText("Simulate");
jButton1.addActionListener(new java.awt.event.ActionListener()
public void actionPerformed(java.awt.event.ActionEvent evt)
jButton1ActionPerformed(evt);
);
jLabel1.setFont(new java.awt.Font("Lucida Console", 0, 20)); // NOI18N
jLabel1.setText("Time = 0");
jLabel3.setFont(new java.awt.Font("Lucida Console", 0, 20)); // NOI18N
jLabel3.setText("Orders = 0");
javax.swing.GroupLayout jPanel1Layout = new javax.swing.GroupLayout(jPanel1);
jPanel1.setLayout(jPanel1Layout);
jPanel1Layout.setHorizontalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createSequentialGroup()
.addContainerGap()
.addComponent(jLabel1, javax.swing.GroupLayout.PREFERRED_SIZE, 130, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 13, Short.MAX_VALUE)
.addComponent(jLabel3, javax.swing.GroupLayout.PREFERRED_SIZE, 130, javax.swing.GroupLayout.PREFERRED_SIZE)
.addGap(206, 206, 206)
.addComponent(fastModeButton, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
.addComponent(jButton1)
.addContainerGap())
);
jPanel1Layout.setVerticalGroup(
jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createSequentialGroup()
.addContainerGap()
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(fastModeButton, javax.swing.GroupLayout.DEFAULT_SIZE, 22, Short.MAX_VALUE)
.addComponent(jButton1, javax.swing.GroupLayout.PREFERRED_SIZE, 20, javax.swing.GroupLayout.PREFERRED_SIZE))
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, jPanel1Layout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
.addComponent(jLabel3, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
.addComponent(jLabel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)))
.addContainerGap())
);
javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
getContentPane().setLayout(layout);
layout.setHorizontalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addComponent(jPanel1, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
);
layout.setVerticalGroup(
layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(javax.swing.GroupLayout.Alignment.TRAILING, layout.createSequentialGroup()
.addContainerGap(401, Short.MAX_VALUE)
.addComponent(jPanel1, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
);
pack();
// </editor-fold>
private void jButton1ActionPerformed(java.awt.event.ActionEvent evt)
try
//buildLines();
sim.build();
for(int i = 0; i<sim.length;i++)
simulate(fastMode);
Thread.sleep(200);
catch (InterruptedException ex)
Logger.getLogger(GUI.class.getName()).log(Level.SEVERE, null, ex);
private void fastModeButtonActionPerformed(java.awt.event.ActionEvent evt)
fastMode = !fastMode;
/**
* @param args the command line arguments
*/
public static void main(String args[])
/* Set the Nimbus look and feel */
//<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
/* If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
* For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
*/
try
for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels())
if ("Nimbus".equals(info.getName()))
javax.swing.UIManager.setLookAndFeel(info.getClassName());
break;
catch (ClassNotFoundException ex)
java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
catch (InstantiationException ex)
java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
catch (IllegalAccessException ex)
java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
catch (javax.swing.UnsupportedLookAndFeelException ex)
java.util.logging.Logger.getLogger(GUI.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
//</editor-fold>
/* Create and display the form */
java.awt.EventQueue.invokeLater(new Runnable()
public void run()
new GUI().setVisible(true);
);
// Variables declaration - do not modify
private javax.swing.JToggleButton fastModeButton;
private javax.swing.JButton jButton1;
private javax.swing.JLabel jLabel1;
private javax.swing.JLabel jLabel3;
private javax.swing.JPanel jPanel1;
// End of variables declaration
【问题讨论】：
我看过了，但他的情况完全不同，以至于我真的不明白如何实施提供给他的解决方案——他只想要 1 次暂停，并且它附加到 ActionListener。 核心问题是一样的，你正在让负责重新绘制 GUI 的线程进入睡眠状态，所以它永远没有时间实际完成工作。您必须使用不涉及休眠主线程的方法来调用simulate。
【参考方案1】：
ActionListener 中的代码在 Event Dispatch THread 上执行。 Thread.sleep(...) 导致 EDT 进入睡眠状态，因此 GUI 无法重新绘制自身，直到整个循环执行完毕。
阅读 Concurrency 上的 Swing 教程部分了解更多信息。
如教程中所述，一个解决方案是使用SwingWorker，然后根据需要“发布”结果。
另一种方法是使用 Swing Timer 来安排更新。该教程还有一个关于How to Use Swing Timers的部分。
【讨论】：
嗯..How to Use Swing Timers 上代码格式的奇怪选择。这似乎是故意的，所以我没有更改它，但它似乎不适合那个 Java Doc 页面标题。 bold 或 italic 怎么样？【参考方案2】：
您尚未在代码中创建 Thread 的对象。您需要创建一个线程，用您的代码覆盖其run() 方法，并通过在您的线程上调用start() 来启动您线程的run() 方法。
private void goButtonActionPerformed(java.awt.event.ActionEvent evt)
new Thread()
public void run()
try
for (int i = 0; i < sim.length; i++)
simulate();
Thread.sleep(500);
catch (Exception e)
e.printStackTrace();
.start();
由于您要从线程更新 gui 元素，您应该使用 invokelater()。
private void simulate()
SwingUtilities.invokeLater(new Runnable()
public void run()
// Here, we can safely update the GUI
// because we'll be called from the
// event dispatch thread
/* HERE YOUR your simulate() code */
);
我认为应该可以。
【讨论】：
这基本上是 SwingWorker 所做的。它创建一个单独的线程并允许您发布结果，以便在 EDT 上执行代码。 哦，好的。还不知道。我以上是关于更新 JFrame 并使用 Thread.sleep() [重复]的主要内容，如果未能解决你的问题，请参考以下文章
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