如何使我的JProgressBar出現在我的JPanel中？

Question

我已經花了很長時間查看該代碼，並且不知道如何讓我的JProgressBar真正出現在GUI上。 當我運行該應用程序時，JLabel會出現在JPanel中，但JProgressBar卻沒有，如何解決此問題？

（注意：JProgressBar確實可以工作和更新，只是它沒有出現在GUI上）

jPanel9.setLayout(new BorderLayout());
    jPanel9.add(new JLabel(theTask.getName() + theTask.getDes()), BorderLayout.NORTH);
    JProgressBar progress = new JProgressBar(0, theTask.getMax());
    progress.setStringPainted(true);
    progress.setBorderPainted(true);
    progress.setValue(theTask.getProgress());
    progress.setString(theTask.getProgress() + "/" + progress.getMaximum());
    progress.setPreferredSize(new Dimension(100,100));
    progress.setVisible(true);
    jPanel9.add(progress, BorderLayout.SOUTH);
    jPanel9.revalidate();
    jPanel9.repaint();

    System.out.println(progress.getString());
    System.out.println("Progress: " + theTask.getProgress());
    System.out.println("Max: " + theTask.getMax());

Answer 1

我通過制作一個自定義面板並將其放到我的gui中來解決了這個問題，這並不是我想要的，但是它完成了工作：

public class ProgressPanel extends javax.swing.JPanel {

/**
 * Creates new form ProgressPanel
 */
public ProgressPanel() {
    initComponents();
    jProgressBar1.setMinimum(0);
}

public ProgressPanel(int max, String s)
{
    jProgressBar1.setMinimum(0);
    jProgressBar1.setMaximum(max);
    changeLabel(s);
    initComponents();
}

public void setMax(int i)
{
    jProgressBar1.setMaximum(i);
}


public void changeProgress(int i)
{
    jProgressBar1.setValue(i);
    jProgressBar1.setString(i + "/" + jProgressBar1.getMaximum());
}


public void changeLabel(String s)
{
    jLabel1.setText(s);
}

/**
 * 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() {

    jLabel1 = new javax.swing.JLabel();
    jProgressBar1 = new javax.swing.JProgressBar();

    setLayout(new java.awt.BorderLayout());

    jLabel1.setFont(new java.awt.Font("Tahoma", 0, 14)); // NOI18N
    jLabel1.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    jLabel1.setText("jLabel1");
    add(jLabel1, java.awt.BorderLayout.PAGE_START);

    jProgressBar1.setFont(new java.awt.Font("Tahoma", 0, 14)); // NOI18N
    add(jProgressBar1, java.awt.BorderLayout.CENTER);
}// </editor-fold>
// Variables declaration - do not modify
private javax.swing.JLabel jLabel1;
private javax.swing.JProgressBar jProgressBar1;
// End of variables declaration