将数据动态添加到AbstractTableModel的Extended类

Question

我有一些从我的数据库加载并作为公共静态列表存储在另一个类中的数据，我无法在MyTableModel类中访问我的数据来存储并在jtable中查看它们... 还有很多其他方法可以用我的数据填充表格，但他们没有给我一个列复选框...我该怎么办？

    class MyTableModel extends AbstractTableModel {
    private String[] columnNames = {"UserName","Admin","Blocked"};
    private Object[Size][3] data;
    //size is an variable thing witch i get it from db,uses as number of the row;
    public int getColumnCount() {
       return columnNames.length;
    }

    public int getRowCount() {
       return data.length;
    }

    public String getColumnName(int col) {
       return columnNames[col];
    }

    public Object getValueAt(int row, int col) {
       return data[row][col];
    }

    public Class getColumnClass(int c) {
       return getValueAt(0, c).getClass();
    }

    public boolean isCellEditable(int row, int col) {
        if (col < 2) {
           return false;
        } else {
           return true;
        }
    }

    public void setValueAt(Object value, int row, int col) {
        data[row][col] = value;
        fireTableCellUpdated(row, col);
    }

    }    

Answer 1

您应该避免使用object.getClass()来返回列的类类型。如果该值恰好是数据集中唯一的null值，会发生什么？

相反，你应该传回实际的列类...（nb没有你实际的数据，我不知道应该传递什么值，所以这只是一个例子......）

public Class getColumnClass(int c) {
    return c < 2 ? String.class : Boolean.class;
}

<强>更新

要让JTable显示JCheckBox，表模型必须从模型Boolean方法返回getColumnClass ...这是最简单的解决方案，然后再次，您可以简单地为特定列提供自定义单元格渲染器。

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.TableModel;

public class TestTable11 {

    public static void main(String[] args) {
        new TestTable11();
    }

    public TestTable11() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException ex) {
                } catch (InstantiationException ex) {
                } catch (IllegalAccessException ex) {
                } catch (UnsupportedLookAndFeelException ex) {
                }

                TableModel model = new SimpleTableModel();

                JFrame frame = new JFrame("Test");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new JScrollPane(new JTable(model)));
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public class SimpleTableModel extends AbstractTableModel {

        private List<Object[]> rows;

        public SimpleTableModel() {
            rows = new ArrayList<>(5);
            rows.add(new Object[]{"Test1", "Test2", false});
            rows.add(new Object[]{"Test3", "Test4", false});
            rows.add(new Object[]{"Test5", "Test6", false});
            rows.add(new Object[]{"Test7", "Test8", false});
            rows.add(new Object[]{"Test9", "Test10", false});
            rows.add(new Object[]{"Test11", "Test11", false});
        }

        @Override
        public int getRowCount() {
            return rows.size();
        }

        @Override
        public int getColumnCount() {
            return 3;
        }

        @Override
        public Object getValueAt(int rowIndex, int columnIndex) {
            return rows.get(rowIndex)[columnIndex];
        }

        @Override
        public boolean isCellEditable(int rowIndex, int columnIndex) {
            return columnIndex == 2;
        }

        @Override
        public Class<?> getColumnClass(int columnIndex) {
            return columnIndex < 2 ? String.class : Boolean.class;
        }

        @Override
        public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
            if (columnIndex == 2 && aValue instanceof Boolean) {
                rows.get(rowIndex)[columnIndex] = aValue;
            }
        }        
    }    
}