停止JTable仅在聚焦并按下键时可编辑

Question

我编写了一个自定义的DefaultCelleditor，这样当我键入示例Jtable的Lengte列时，除了数字之外什么都不能输入。

如果用户单击单元格一次，然后开始键入，同时仍然允许用户双击单元格开始编辑，我如何防止用户能够编辑单元格？

import java.awt.Color;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.lang.reflect.Constructor;

import javax.swing.DefaultCellEditor;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.border.LineBorder;

@SuppressWarnings("serial")
public class JTableTest extends JFrame {
    private JTableTest() {
        super("JTable Test");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new GridLayout(1, 1));
        createPanel();
        pack();
        setVisible(true);
    }

    JPanel panel = new JPanel(new GridLayout(1, 1));
    JScrollPane scroll;

    private void createPanel() {
        Object[] headers = {"Length", "Title"};
        Object[][] sampleData = {{"673", "Bat Outta Hell"},
                {"358", "Spanish Train"},
                {"673", "Bat Outta Hell"}};
        JTable table = new JTable(sampleData, headers);
        table.setDefaultEditor(Object.class, new NumEditor());
        scroll = new JScrollPane(table);
        panel.add(scroll);
        getContentPane().add(panel);
    }

    private class NumEditor extends DefaultCellEditor {
        Class<?>[] argTypes = new Class<?>[]{String.class};
        Constructor<?> constructor;
        Object value;

        public NumEditor() {
            super(new JTextField());
            getComponent().setName("Table.editor");
        }

        public boolean stopCellEditing() {
            String s = (String)super.getCellEditorValue();
            try {
                if ("".equals(s)) {
                    if (constructor.getDeclaringClass() == String.class) {
                        value = s;
                    }
                    return super.stopCellEditing();
                }
                value = constructor.newInstance(new Object[]{s});
            }
            catch (Exception e) {
                ((JComponent)getComponent()).setBorder(new LineBorder(Color.red));
                return false;
            }
            return super.stopCellEditing();
        }

        public Component getTableCellEditorComponent(JTable table, Object value, boolean isSelected, int row, int column) {
            this.value = null;
            ((JComponent)getComponent()).setBorder(new LineBorder(Color.black));
            try {
                Class<?> type = table.getColumnClass(column);

                if (type == Object.class) {
                    type = String.class;
                }

                KeyListener kL = new KeyListener() {
                    public void keyPressed(KeyEvent e) {

                    }
                    public void keyReleased(KeyEvent e) {

                    }
                    public void keyTyped(KeyEvent e) {
                        char c = e.getKeyChar();
                        if(Character.isDigit(c)){

                        } else {
                            e.consume();
                        }
                    }
                };

                if(column == 0)
                    ((JComponent)getComponent()).addKeyListener(kL);
                else
                    ((JComponent)getComponent()).removeKeyListener(kL);

                constructor = type.getConstructor(argTypes);
            }
            catch (Exception e) {
                return null;
            }
            return super.getTableCellEditorComponent(table, value, isSelected, row, column);
        }

        public Object getCellEditorValue() {
            return value;
        }
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(() -> new JTableTest());
    }
}

Answer 1

查看celleditor.iscelleditable(EventObject anEvent)。AbstractCelleditor和DefaultCelleditor实现Celleditor接口。

如果EventObject是KeyEvent类型的实例，则可以重写此方法以返回false。否则返回super.iscelleditable(anEvent)。