即使使用SwingWorker,Java GUI也会冻结

Question

我正在尝试使用SwingWorker执行冗长的任务并使用结果更新JLabel:

button.addActionListener(new ActionListener() {

    @Override
    public void actionPerformed(ActionEvent arg0) {
        new SwingWorker<String, Void>() {

            @Override
            protected String doInBackground() throws Exception {
                return doCalculation();
            }

            protected void done() {
                try {
                    label.setText(get());
                } catch (InterruptedException e) {
                    System.out.println("thread was interrupted");
                } catch (ExecutionException e) {
                    System.out.println("there was an ExecutionException");
                }
            }

        }.execute();

    }

});

我可以随意点击按钮多次,Gui将保持响应,直到两个线程完成,此时Gui在线程运行时冻结.如果我一次只运行一个线程,则仍会出现此问题.

如果有人能指出我是否错误地使用了SwingWorker,或者是否有其他我不知道的问题,我会很高兴.谢谢你的时间.伊恩

编辑

doCalculation()只是耗费时间:

private String doCalculation() {
    for (int i = 0; i < 10000000; i++) {
        Math.pow(3.14, i);
    }
    return threads++ + "";
}

Answer 1

对不起,但即使你的doCalculate()方法,我仍然无法重现你的问题.例如,这是我的sscce:

import java.awt.event.*;
import java.util.concurrent.ExecutionException;
import javax.swing.*;

public class FooGui {
   private static int threads = 0;

   private static void createAndShowUI() {
      final JLabel label = new JLabel("      ");
      JButton button = new JButton("Button");
      button.addActionListener(new ActionListener() {

         @Override
         public void actionPerformed(ActionEvent arg0) {
            new SwingWorker<String, Void>() {

               @Override
               protected String doInBackground() throws Exception {
                  return doCalculation();
               }

               @Override
               protected void done() {
                  try {
                     label.setText(get());
                  } catch (InterruptedException e) {
                     System.out.println("thread was interrupted");
                  } catch (ExecutionException e) {
                     System.out.println("there was an ExecutionException");
                  }
               }
            }.execute();
         }
      });
      JPanel panel = new JPanel();
      panel.add(button);
      panel.add(label);

      JFrame frame = new JFrame("FooGui");
      frame.getContentPane().add(panel);
      frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      frame.pack();
      frame.setLocationRelativeTo(null);
      frame.setVisible(true);
   }

   private static String doCalculation() {
      for (int i = 0; i < 5000000; i++) {
         Math.pow(3.14, i);
      }
      return threads++ + "";
   }

   public static void main(String[] args) {
      java.awt.EventQueue.invokeLater(new Runnable() {

         @Override
         public void run() {
            createAndShowUI();
         }
      });
   }
}

您可能希望创建并发布自己的"简短,自包含,正确(可编译),示例"或SSCCE(请查看链接).我敢打赌,在创建这个过程中,您可能会自己找到问题及其解决方案.如果是这样,请务必回到这里告诉我们.

我知道这不是一个真正的答案,但是没有办法在评论中发布这样的代码.