按下按钮后，JPanel不会显示更新

Question

我有以下JPanel，它包含一个按钮和一个JScrollPane。

当按下按钮时，我希望它在JScrollPane中添加JPanel的新行。问题是什么都没有出现。我的代码如下，我很难过。

// swing imports
import javax.swing.JPanel;
import javax.swing.JLabel;
import javax.swing.JTextField;
import javax.swing.JCheckBox;
import javax.swing.JButton;
import javax.swing.JScrollPane;
// awt imports
import java.awt.Color;
import java.awt.Insets;
import java.awt.BorderLayout;
import java.awt.GridBagLayout;
import java.awt.GridBagConstraints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class DBPediaPanel extends JPanel {

    private JScrollPane scrollPane;
    private JPanel scrollContent;
    private JButton btnAcceptAll;
    private int currentRow = 0;

    public DBPediaPanel() {
        this.setLayout(new BorderLayout());
        this.setBackground(Color.BLACK);

        this.add(getScrollPane(), BorderLayout.CENTER);

        btnAcceptAll = new JButton("Add Row");
        btnAcceptAll.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                addStringToList("row " + currentRow);
                System.out.println("test");
            }
        });
        this.add(btnAcceptAll, BorderLayout.SOUTH);
    }

    private JScrollPane getScrollPane() {
        scrollContent = new JPanel(new GridBagLayout());;

        scrollPane = new JScrollPane(scrollContent);
        return scrollPane;
    }

    private GridBagConstraints createGbc(int x, int y) {
        GridBagConstraints gbc = new GridBagConstraints();
        gbc.gridx = x;
        gbc.gridy = y;
        gbc.gridwidth = 1;
        gbc.gridheight = 1;

        gbc.anchor = (x == 0) ? GridBagConstraints.WEST : GridBagConstraints.EAST;
        //gbc.fill = (x == 0) ? GridBagConstraints.NONE : GridBagConstraints.HORIZONTAL;

        gbc.insets = (y == 0) ? new Insets(3, 5, 3, 5) : new Insets(0, 5, 3, 5);
        gbc.weightx = (x == 0) ? 0.1 : 1.0;
        gbc.weighty = 1.0;

        return gbc;
    }

    public void addStringToList(String str) {
        System.out.println("in addStringToList");
        System.out.println("attempting to add " + str + " to the list");

        GridBagConstraints gbc = createGbc(0, currentRow);
        scrollContent.add(new JCheckBox(), gbc);

        gbc = createGbc(1, currentRow);
        scrollContent.add(new JTextField(str), gbc);
        scrollContent.repaint();
        scrollPane.repaint();

        currentRow++;
    }

}

Answer 1

通过重新验证scrollContent解决了这个问题。感谢mre