Progressmonitor在JavaSwing中不显示
Progressmonitor在JavaSwing中不显示
提问于 2015-03-14 05:49:06
我正在创建一个简单的用户界面，用户可以通过单击按钮来运行特定的Java类。单击后，应向用户显示任务的进度，并提供一个取消按钮，供用户在任务运行期间的任何时间点终止任务。
在本例中，我使用了一个ProgressMonitor，当用户单击UI中的JButton时将显示该UI，从而调用包含runnable线程的runEngineerBuild()来执行另一个类(称为EngineerBuild.java)的方法。但是，不会显示ProgressMonitor对话框。如何才能显示ProgressDialog？我想知道这是不是因为多个运行线程的性质，或者我错过了什么。会非常感谢你的帮助！
在SecondPanel.java中：
package mainApplication;
import java.awt.Font;
public class SecondPanel extends JPanel {
private MainApplication ma = null; // main JFrame
private JPanel pnlBtn;
private JPanel pnlProgress;
private JButton btnRunAll;
private JButton btnEngBuild;
private JButton btnWholeDoc;
private JButton btnCancelProgress;
private JLabel lblTitleSteps;
private JLabel lblAlt;
private JLabel lbl_1a;
private JLabel lbl_1b_c;
private JLabel lblTitleStatus;
private JProgressBar progressRunAll;
private JProgressBar progressEngBuild;
private JProgressBar progressWholeDoc;
private Property property = Property.getInstance();
// private Task task;
private boolean cancelFlag;
/**
* Create the panel for Step 1 TabbedPane.
*/
public SecondPanel(MainApplication mainApp) {
// TODO Auto-generated constructor stub
super();
ma = mainApp;
}
public SecondPanel() {
this.setBackground(new Color(224, 255, 255));
this.setBounds(0, 0, 745, 1350);
this.setPreferredSize(new Dimension(745, 600));
this.setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
pnlBtn = new JPanel();
pnlBtn.setLayout(new BoxLayout(pnlBtn, BoxLayout.PAGE_AXIS));
pnlBtn.setAlignmentY(Component.TOP_ALIGNMENT);
pnlProgress = new JPanel();
pnlProgress.setLayout(new BoxLayout(pnlProgress, BoxLayout.PAGE_AXIS));
pnlProgress.setAlignmentY(TOP_ALIGNMENT);
pnlBtn.add(Box.createRigidArea(new Dimension(0, 15)));
btnEngBuild = new JButton("Run EngineerBuild.java");
btnEngBuild.setToolTipText("Build search engineer");
btnEngBuild.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent event) {
// start activity
activity = new SimulatedActivity(1000);
activity.start();
// launch progress dialog
progressDialog = new ProgressMonitor(ma,
"Waiting for Simulated Activity", null, 0, activity
.getTarget());
progressDialog.setMillisToPopup(1000);
// start timer
activityMonitor = new Timer(500, null);
activityMonitor.start();
btnEngBuild.setEnabled(false);
}
});
activityMonitor = new Timer(500, new ActionListener() {
private PrintStream textArea;
public void actionPerformed(ActionEvent event) {
int current = activity.getCurrent();
// show progress
runEngineerBuild();
textArea.append(current + "\n");
progressDialog.setProgress(current);
// check if task is completed or canceled
if (current == activity.getTarget() || progressDialog.isCanceled()) {
activityMonitor.stop();
progressDialog.close();
activity.interrupt();
btnEngBuild.setEnabled(true);
}
}
});
btnEngBuild.setMinimumSize(new Dimension(200, 30));
btnEngBuild.setPreferredSize(new Dimension(200, 30));
btnEngBuild.setMaximumSize(new Dimension(200, 30));
pnlBtn.add(btnEngBuild);
pnlBtn.add(Box.createRigidArea(new Dimension(0, 15)));
// components in panel progress
lblTitleStatus = new JLabel();
lblTitleStatus.setText("<html><u>Task Status</u></html>");
progressEngBuild = new JProgressBar();
Border border2 = BorderFactory.createTitledBorder("Run EngineerBuild");
progressEngBuild.setBorder(border2);
// title
pnlProgress.add(lblTitleStatus);
pnlProgress.add(Box.createRigidArea(new Dimension(0, 15)));
pnlProgress.add(progressEngBuild);
pnlProgress.add(Box.createRigidArea(new Dimension(0, 15)));
this.add(Box.createRigidArea(new Dimension(15, 10)));
this.add(pnlBtn);
this.add(Box.createRigidArea(new Dimension(50, 10)));
this.add(pnlProgress);
}
public void runEngineerBuild()
{
EngineerBuildRunnable ebr = new EngineerBuildRunnable();
ebr.run();
}
private class EngineerBuildRunnable implements Runnable {
EngineerBuild eb;
public EngineerBuildRunnable() {
eb = new EngineerBuild();
}
public void run() {
eb.initial();
eb.storeIntoFile();
}
}
private Timer activityMonitor;
private ProgressMonitor progressDialog;
private SimulatedActivity activity;
public static final int WIDTH = 300;
public static final int HEIGHT = 200;
}
/**
* A simulated activity thread.
*/
class SimulatedActivity extends Thread {
/**
* Constructs the simulated activity thread object. The thread increments a
* counter from 0 to a given target.
*
* @param t
* the target value of the counter.
*/
public SimulatedActivity(int t) {
current = 0;
target = t;
}
public int getTarget() {
return target;
}
public int getCurrent() {
return current;
}
public void run() {
try {
while (current < target && !interrupted()) {
sleep(100);
current++;
}
} catch (InterruptedException e) {
}
}
private int current;
private int target;
}
如果你感兴趣，这里有原始ProgressMonitor代码的链接：
User Interface Programming - Example 1-11 ProgressMonitorTest.java
回答 1
Stack Overflow用户
发布于 2015-03-14 05:56:01
很有可能，调用runEngineerBuild()将调用长时间运行的代码，这就是您在Swing事件线程上所做的事情，这将占用线程，使您的图形用户界面变得无用并冻结，直到长时间运行的代码完成其运行。解决方案与所有类似问题都是一样的--在后台线程(如SwingWorker )中调用runEngineerBuild()。
一种快速的解决方法是在一个简单的线程中显式调用runEngineerBuild()：
EngineerBuildRunnable ebr = new EngineerBuildRunnable();
new Thread(ebr).start();
// ebr.run(); // !!! don't call a Runnable's run method directly !!!!有关如何使用SwingWorker的详细信息，请查看：Lesson: Concurrency in Swing。
页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：
https://stackoverflow.com/questions/29042545
复制相关文章
相似问题
腾讯云开发者
Copyright © 2013 - 2026 Tencent Cloud. All Rights Reserved. 腾讯云 版权所有
深圳市腾讯计算机系统有限公司 ICP备案/许可证号：粤B2-20090059 
粤公网安备44030502008569号
腾讯云计算（北京）有限责任公司 京ICP证150476号 | 京ICP备11018762号