java - 覆盖 CellRenderer，ImageIcon 消失

Question

Hovercraft Full of Eels 已经为我提供了 TableCellRenderer，但现在:我可以毫无问题地画一个圆。我只是对原始 ImageIcons(在所有单元格内)如何被空单元格和黑色圆圈覆盖感到困惑。

上海商会:

package sccee;

import java.awt.Graphics;
import java.net.URL;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JTable;
import javax.swing.SwingWorker;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;

public class SCCEE extends JFrame {

    private JTable spelbordTabel;
    URL url = this.getClass().getResource("/resources/leeg.png");
    ImageIcon leeg = new ImageIcon(new ImageIcon(url).getImage().getScaledInstance(100, 100, java.awt.Image.SCALE_SMOOTH));

    public static void main(String[] args) {
        java.awt.EventQueue.invokeLater(() -> {
            SCCEE testFrame = new SCCEE();
            testFrame.setBounds(0, 0, 700, 700);
            testFrame.setVisible(true);
        });

    }

    public SCCEE() {
        initComponents();
        updateTableImages();
    }

    private void initComponents() {
        spelbordTabel = new javax.swing.JTable();
        spelbordTabel.setModel(new DefaultTableModel(new Object[][]{
            {null, null, null, null, null, null, null},
            {null, null, null, null, null, null, null},
            {null, null, null, null, null, null, null},
            {null, null, null, null, null, null, null},
            {null, null, null, null, null, null, null},
            {null, null, null, null, null, null, null},
            {null, null, null, null, null, null, null},},
                new String[]{
                    "Title 1", "Title 2", "Title 3", "Title 4", "Title 5", "Title 6", "Title 7"
                }) {

                    @Override
                    public Class
                    getColumnClass(int columnIndex) {
                        return ImageIcon.class;
                    }
                    boolean[] canEdit = new boolean[]{false, false, false, false, false, false, false};

                    @Override
                    public boolean isCellEditable(int rowIndex, int columnIndex) {
                        return canEdit[columnIndex];
                    }

                });
        spelbordTabel.setAutoscrolls(false);
        spelbordTabel.setCursor(new java.awt.Cursor(java.awt.Cursor.HAND_CURSOR));
        spelbordTabel.setOpaque(false);
        spelbordTabel.setRequestFocusEnabled(false);
        spelbordTabel.setRowHeight(100);
        spelbordTabel.setRowSelectionAllowed(false);
        spelbordTabel.setTableHeader(null);
        spelbordTabel.setUpdateSelectionOnSort(false);
        spelbordTabel.setVerifyInputWhenFocusTarget(false);
        spelbordTabel.setBounds(0, 0, 700, 700);
        spelbordTabel.setBorder(new javax.swing.border.LineBorder(new java.awt.Color(0, 0, 0), 4, true));
        spelbordTabel.setDragEnabled(true);
        spelbordTabel.setVisible(true);
        spelbordTabel.getColumn("Title 1").setCellRenderer(
                new DefaultTableCellRenderer() {
                    @Override
                    public void paintComponent(Graphics g) {
                        super.paintComponent(g);
                        g.fillOval(30, 30, 20, 20);
                    }

                }
        );
        add(spelbordTabel);
    }

    public void updateTableImages() {
        SwingWorker<Void, Void> worker2 = new SwingWorker<Void, Void>() {
            @Override
            protected Void doInBackground() throws InterruptedException {
                Thread.sleep(50);
                for (int i = 0; i < 7; i++) {
                    for (int j = 0; j < 7; j++) {
                        spelbordTabel.setValueAt(leeg, i, j);
                    }
                }
                return null;
            }

        };
        worker2.execute();
    }
}

我遗漏了什么明显的东西吗？ (第一次摆弄 tablecellrenderers)。

Answer 1

我不是 100% 清楚您的实际问题是什么，但相信您的问题可以通过为您的 JTable 创建自定义表格单元格渲染器来解决，这样每​​个单元格都可以绘制所需的任何圆圈。