java - J表:Swing: Dynamic button name is not coming

Question

我为每一行动态生成一个新按钮，我希望该按钮名称为“编辑”。 我收到了该按钮，但无法将该按钮命名为“编辑”，

基于此example ，这是我尝试过的:

import java.awt.Component;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

import javax.swing.DefaultCellEditor;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableCellRenderer;

/**
 * @version 1.0 11/09/98
 */
public class JButtonTableExample extends JFrame {

  public JButtonTableExample() {
    super("JButtonTable Example");

    DefaultTableModel dm = new DefaultTableModel();
    dm.setDataVector(new Object[][] { { "button 1", "foo" },
        { "button 2", "bar" } }, new Object[] { "Button", "String","Edit" });

    JTable table = new JTable(dm);
    table.getColumn("Edit").setCellRenderer(new ButtonRenderer());
    table.getColumn("Edit").setCellEditor(
        new ButtonEditor(new JCheckBox()));
    JScrollPane scroll = new JScrollPane(table);
    getContentPane().add(scroll);
    setSize(400, 100);
    setVisible(true);
  }

  public static void main(String[] args) {


    JButtonTableExample frame = new JButtonTableExample();
    frame.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(0);
      }
    });
  }
}
/**
 * @version 1.0 11/09/98
 */

class ButtonRenderer extends JButton implements TableCellRenderer {

  public ButtonRenderer() {
    setOpaque(true);
  }

  public Component getTableCellRendererComponent(JTable table, Object value,
      boolean isSelected, boolean hasFocus, int row, int column) {
    if (isSelected) {
      setForeground(table.getSelectionForeground());
      setBackground(table.getSelectionBackground());
    } else {
      setForeground(table.getForeground());
      setBackground(UIManager.getColor("Button.background"));
    }
    setText((value == null) ? "" : value.toString());
    return this;
  }
}

/**
 * @version 1.0 11/09/98
 */

class ButtonEditor extends DefaultCellEditor {
  protected JButton button;

  private String label;

  private boolean isPushed;

  public ButtonEditor(JCheckBox checkBox) {
    super(checkBox);
    button = new JButton("Edit");
    button.setOpaque(true);
    button.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        fireEditingStopped();
      }
    });
  }

  public Component getTableCellEditorComponent(JTable table, Object value,
      boolean isSelected, int row, int column) {
    if (isSelected) {
      button.setForeground(table.getSelectionForeground());
      button.setBackground(table.getSelectionBackground());
    } else {
      button.setForeground(table.getForeground());
      button.setBackground(table.getBackground());
    }
    label = (value == null) ? "" : value.toString();
    button.setText(label);
    isPushed = true;
    return button;
  }

  public Object getCellEditorValue() {
    if (isPushed) {
      // 
      // 
      JOptionPane.showMessageDialog(button, label + ": Ouch!");
      // System.out.println(label + ": Ouch!");
    }
    isPushed = false;
    return new String(label);
  }

  public boolean stopCellEditing() {
    isPushed = false;
    return super.stopCellEditing();
  }

  protected void fireEditingStopped() {
    super.fireEditingStopped();
  }
}

谁能告诉我哪里错了!!! 我不明白为什么按钮名称没有出现

Answer 1

这是因为您在此处专门将按钮的文本设置为 ""，

setText((value == null) ? "" : value.toString());

在TableCellRenderer.getTableCellRenderer() 方法中。当呈现表格时，会为每个单元格调用此方法。并且该值设置为null。

修复使用:

setText((value == null) ? "Edit" : value.toString());