我修改了您的 sscce 以显示建议的替代方法here。请注意获得的替代方法Double
持续的。我还重新考虑了String
限制。
附录:在有用的评论中,@kleopatra 观察到直接查询模型总是会产生正确的结果,但是TableModelListener
只会看到第 0 列的更改,而不是第 1 列。简单的权宜之计是更改第 1 列non-可编辑,因为它的值完全取决于第 0 列。
@Override
public boolean isCellEditable(int row, int col) {
return col == 0;
}
下面的第一个示例使用DefaultTableModel
:
import javax.swing.*;
import javax.swing.table.*;
/** @see https://stackoverflow.com/a/13628183/230513 */
public class ExampleRemoveAddRows extends JFrame {
public static final String NEGATIVE = "negativ";
public static final String POSITIVE = "positiv";
private Object[] columnNames = {"Double", POSITIVE + " / " + NEGATIVE};
private Object[][] data = {
{10d, null},
{-10.0, null},
{Double.valueOf(30), null},
{Double.valueOf("-30"), null}
};
private JTable table;
private DefaultTableModel model;
public ExampleRemoveAddRows() {
model = new DefaultTableModel(data, columnNames) {
@Override
public Class getColumnClass(int column) {
return getValueAt(0, column).getClass();
}
@Override
public boolean isCellEditable(int row, int col) {
return col == 0;
}
@Override
public Object getValueAt(int row, int col) {
if (col == 1) {
double number = (Double) this.getValueAt(row, 0);
return (number < 0) ? NEGATIVE : POSITIVE;
} else {
return super.getValueAt(row, col);
}
}
@Override
public void setValueAt(Object aValue, int row, int col) {
super.setValueAt(aValue, row, col);
fireTableCellUpdated(row, 1); // may have changed
}
};
table = new JTable(model);
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
ExampleRemoveAddRows frame = new ExampleRemoveAddRows();
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
这种变化extends AbstractTableModel
:
import java.awt.EventQueue;
import java.util.ArrayList;
import java.util.List;
import javax.swing.*;
import javax.swing.table.*;
/**
* @see https://stackoverflow.com/a/13628183/230513
*/
public class ExampleRemoveAddRows extends JFrame {
public static final String NEGATIVE = "negativ";
public static final String POSITIVE = "positiv";
public ExampleRemoveAddRows() {
DoubleModel model = new DoubleModel();
model.add(10.1);
model.add(-10.2);
model.add(Double.valueOf(30.1));
model.add(Double.valueOf("-30.2"));
JTable table = new JTable(model);
table.setPreferredScrollableViewportSize(table.getPreferredSize());
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
ExampleRemoveAddRows frame = new ExampleRemoveAddRows();
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private class DoubleModel extends AbstractTableModel {
List<Double> data = new ArrayList<Double>();
public void add(Double d) {
data.add(d);
}
@Override
public int getRowCount() {
return data.size();
}
@Override
public int getColumnCount() {
return 2;
}
@Override
public String getColumnName(int col) {
if (col == 0) {
return "Double";
} else {
return POSITIVE + " / " + NEGATIVE;
}
}
@Override
public Class<?> getColumnClass(int col) {
if (col == 0) {
return Double.class;
} else {
return String.class;
}
}
@Override
public boolean isCellEditable(int row, int col) {
return col == 0;
}
@Override
public Object getValueAt(int row, int col) {
if (col == 0) {
return data.get(row);
} else {
double number = (Double) this.getValueAt(row, 0);
return (number < 0) ? NEGATIVE : POSITIVE;
}
}
@Override
public void setValueAt(Object aValue, int row, int col) {
if (col == 0) {
data.set(row, (Double) aValue);
fireTableRowsUpdated(row, row);
}
}
}
}