java - 进度条可以在 main 之外的类中使用吗？

Question

现在，我的 main 只调用了一个 10 行的 gui。根据这些行中有多少有文本，调用 9 个类中的 1 个(两行必须有文本)。被调用的类执行我希望将进度条绑定(bind)到的计算。这是一个被调用类的示例(每个类都相似，但差异足以保证一个新类。)我认为问题是违反 EDT 规则，但我在它们上看到的所有示例都涉及一个主要的争论。代码运行时会出现框架，但在所有计算完成之前进度条不会更新。

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

public class twoLoan extends JFrame {

    static JFrame progressFrame;
    static JProgressBar progressBar;
    static Container pane;
    double amountSaved = 0;
    int i = 0;

    public void runCalcs(Double MP, Double StepAmt,
        Double L1, Double L2, Double C1, Double C2,
        Double IM1, Double IM2, Double M1Start, Double M2Start) {

        try {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } catch (Exception e) {
        }

        int iterations = (int) (MP - (M1Start * M2Start));

        //Create all components
        progressFrame = new JFrame("Calculation Progress");
        progressFrame.setSize(300, 100);
        pane = progressFrame.getContentPane();
        pane.setLayout(null);
        progressFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        progressBar = new JProgressBar(0, iterations);

        //Add components to pane
        pane.add(progressBar);

        //Position controls (X, Y, width, height)
        progressBar.setBounds(10, 10, 280, 20);

        //Make frame visible
        progressFrame.setResizable(false); //No resize
        progressFrame.setVisible(true);

        double M1 = M1Start;
        double M2 = M2Start;

        // Set MinLoop as maximum to start
        // Loan 1
        double N1 = (Math.log10(1 - IM1 * L1 / M1) * -1) / Math.log10(1 + IM1);
        double M1Sum = M1 * N1;
        // Loan 2
        double N2 = (Math.log10(1 - IM2 * L2 / M2) * -1) / Math.log10(1 + IM2);
        double M2Sum = M2 * N2;
        double minLoop = M1Sum + M2Sum;
        double MTotal = 0;


        // Define variables for mins
        double MP1 = 0;
        double MP2 = 0;
        double NP1 = 0;
        double NP2 = 0;
        double MP1Sum = 0;
        double MP2Sum = 0;

        while (M1 <= MP - M2Start && M2 >= M2Start) {
            N1 = (Math.log10(1 - IM1 * L1 / M1) * -1) / Math.log10(1 + IM1);
            M1Sum = N1 * M1;
            N2 = (Math.log10(1 - IM2 * L2 / M2) * -1) / Math.log10(1 + IM2);
            M2Sum = N2 * M2;
            MTotal = M1Sum + M2Sum;
            if (MTotal < minLoop) {
                minLoop = MTotal;
                MP1 = M1;
                MP2 = M2;
                NP1 = N1;
                NP2 = N2;
                MP1Sum = M1Sum;
                MP2Sum = M2Sum;
            } // end if
            M1 = M1 + StepAmt;
            M2 = MP - M1;
            // Reset monthly sums
            M1Sum = 0;
            M2Sum = 0;
            i++;
            progressBar.setValue(i);
            progressBar.repaint();
            if (i >= iterations) {
                progressFrame.dispose();
            }
        } // end while

        // if there's a value for current payments, calculate amount saved
        if (C1 > 0) {
            double CN1 = (Math.log10(1 - IM1 * L1 / C1) * -1) / Math.log10(1 + IM1);
            double CT1 = CN1 * C1;

            double CN2 = (Math.log10(1 - IM2 * L2 / C2) * -1) / Math.log10(1 + IM2);
            double CT2 = CN2 * C2;

            double CTotal = CT1 + CT2;
            amountSaved = CTotal - minLoop;
        }

    } // end method runCalcs

    //Workbook wb = new HSSFWorkbook();
    public double savedReturn() {
        return amountSaved;
    }
} // end class twoLoans  

Answer 1

SwingWorker非常适合这个。下面的示例在后台执行简单的迭代，同时在窗口中报告进度和中间结果。您可以在合适的 SwingWorker 中传递所需的任何参数构造函数。

import java.awt.EventQueue;
import java.awt.GridLayout;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.text.DecimalFormat;
import java.util.List;
import javax.swing.*;

/** @see http://stackoverflow.com/questions/4637215 */
public class TwoRoot extends JFrame {

    private static final String s = "0.000000000000000";
    private JProgressBar progressBar = new JProgressBar(0, 100);
    private JLabel label = new JLabel(s, JLabel.CENTER);

    public TwoRoot() {
        this.setLayout(new GridLayout(0, 1));
        this.setTitle("√2");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.add(progressBar);
        this.add(label);
        this.setSize(161, 100);
        this.setLocationRelativeTo(null);
        this.setVisible(true);
    }

    public void runCalc() {
        progressBar.setIndeterminate(true);
        TwoWorker task = new TwoWorker();
        task.addPropertyChangeListener(new PropertyChangeListener() {

            @Override
            public void propertyChange(PropertyChangeEvent e) {
                if ("progress".equals(e.getPropertyName())) {
                    progressBar.setIndeterminate(false);
                    progressBar.setValue((Integer) e.getNewValue());
                }
            }
        });
        task.execute();
    }

    private class TwoWorker extends SwingWorker<Double, Double> {

        private static final int N = 5;
        private final DecimalFormat df = new DecimalFormat(s);
        double x = 1;

        @Override
        protected Double doInBackground() throws Exception {
            for (int i = 1; i <= N; i++) {
                x = x - (((x * x - 2) / (2 * x)));
                setProgress(i * (100 / N));
                publish(Double.valueOf(x));
                Thread.sleep(1000); // simulate latency
            }
            return Double.valueOf(x);
        }

        @Override
        protected void process(List<Double> chunks) {
            for (double d : chunks) {
                label.setText(df.format(d));
            }
        }
    }

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

            @Override
            public void run() {
                TwoRoot t = new TwoRoot();
                t.runCalc();
            }
        });
    }
}