java - jtable tablecellrenderer 不执行任何操作

Question

我试图进行检查，如果单元格 3 的值不为空，则整行将被着色为绿色，但是这不会执行任何操作，但是，如果我不进行检查，则仅检查以确保没有任何内容已选择(以便选择会给出颜色以表明您确实选择了)所有内容都绘制为绿色。

if (!table.isRowSelected(row))
            {
                component.setBackground(getBackground());


                if(table.getModel().getValueAt(row, 3).equals(""))
                {
                component.setBackground(Color.GREEN);
                }
            }

我尝试输出该值，一切正常，这里有问题吗？有不同的方法吗？谢谢

Answer 1

I tried to output the value and everything works properly, is there a problem here? A different way of doing this?

我们需要更多代码/信息来正确回答这个问题:

• 如何实现 TableCellRenderer ？是通过扩展 DefaultTableCellRenderer ？
• 如何将 TableCellRenderer 设置为 JTable ？
• 3 是正确的模型列索引吗？

无论如何，我建议您查看Using Custom Renderer How to Use Tables 中的部分踪迹。您还可以查看下面的示例并将其作为起点:

import java.awt.Color;
import java.awt.Component;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;

public class Demo {

    private void initGUI() {

        DefaultTableModel model = new DefaultTableModel(new Object[]{"Manufacturer", "Model", "Country", "Price"}, 0);
        model.addRow(new Object[]{"Fender", "Stratocaster", "Japan", ""});
        model.addRow(new Object[]{"Gibson", "Les Paul", "USA", "$ 1599"});
        model.addRow(new Object[]{"Jackson", "Soloist S3", "Japan","$ 1299"});
        model.addRow(new Object[]{"Paul Reed Smith","Standard 24", "USA", ""});

        JTable table = new JTable(model);

        table.setDefaultRenderer(Object.class, new DefaultTableCellRenderer(){
            @Override
            public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {                
                super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
                if(!isSelected){
                    Color background = table.getModel().getValueAt(row, 3).equals("") ? Color.GREEN : table.getBackground();
                    setBackground(background);
                } else {
                    setBackground(table.getSelectionBackground());
                }
                return this;
            }            
        });

        JFrame frame = new JFrame("Demo");      
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.getContentPane().add(new JScrollPane(table));
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {   
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new Demo().initGUI();
            }
        });
    }
}

图片