如何在单元格编辑后维护JTable单元格渲染

Question

你们在我的上一个问题上指出了正确的方向,你们真是太棒了,我在这里有一些原始问题的扩展:

如何将JTable列设置为String并排序为Double？

我现在通过使用我的自定义单元格渲染器将我的价格列格式化为$ ###,## 0.00,我现在也为单元格设置了一个JTextField编辑器.编辑单元格工作正常,除了更新值时,我的自定义渲染器中设置的数字格式似乎不再格式化单元格(我在编辑提交后丢失了$).即使在初始显示数据之后,此渲染器是否也不应渲染单元格？

我试过使用以下但没有运气:

((AbstractTableModel) table.getModel()).fireTableDataChanged();

我希望这会强制表重新验证并使用自定义渲染器重新绘制单元格以呈现新值,但遗憾的是这不起作用...

我错过了什么......显然,但是什么？

Answer 1

当编辑器结束时,表的editingStopped()方法通过getCellEditorValue()并setValueAt()在模型中使用它来收集新值.反过来,模型应该 fireTableCellUpdated()调用规定的渲染器.扩展默认值应该足以处理Number格式化.在其他情况下,使用渲染器的实例作为编辑器组件可能会很方便; 此示例显示了典型的实现.

附录:这是使用默认编辑器和渲染器实现的基本示例.

附录:感谢@mKorbel的有用评论,我更新了示例以选择单元格的文本进行编辑,如@ camickr的文章表选择所有编辑器中所述.

package overflow;

import java.awt.Component;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.MouseEvent;
import java.text.NumberFormat;
import java.util.EventObject;
import javax.swing.DefaultCellEditor;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.table.DefaultTableCellRenderer;
import javax.swing.table.DefaultTableModel;
import javax.swing.text.JTextComponent;

/** @see http://stackoverflow.com/a/10067560/230513 */
public class RenderEditNumber extends JPanel {

    private NumberFormat nf = NumberFormat.getCurrencyInstance();

    public RenderEditNumber() {
        DefaultTableModel model = new DefaultTableModel(
            new String[]{"Amount"}, 0) {

            @Override
            public Class<?> getColumnClass(int columnIndex) {
                return Double.class;
            }
        };
        for (int i = 0; i < 16; i++) {
            model.addRow(new Object[]{Double.valueOf(i)});
        }
        JTable table = new JTable(model) {

            @Override // Always selectAll()
            public boolean editCellAt(int row, int column, EventObject e) {
                boolean result = super.editCellAt(row, column, e);
                final Component editor = getEditorComponent();
                if (editor == null || !(editor instanceof JTextComponent)) {
                    return result;
                }
                if (e instanceof MouseEvent) {
                    EventQueue.invokeLater(new Runnable() {

                        @Override
                        public void run() {
                            ((JTextComponent) editor).selectAll();
                        }
                    });
                } else {
                    ((JTextComponent) editor).selectAll();
                }
                return result;
            }
        };
        table.setPreferredScrollableViewportSize(new Dimension(123, 123));
        table.setDefaultRenderer(Double.class, new CurrencyRenderer(nf));
        table.setDefaultEditor(Double.class, new CurrencyEditor(nf));
        this.add(new JScrollPane(table));
    }

    private static class CurrencyRenderer extends DefaultTableCellRenderer {

        private NumberFormat formatter;

        public CurrencyRenderer(NumberFormat formatter) {
            this.formatter = formatter;
            this.setHorizontalAlignment(JLabel.RIGHT);
        }

        @Override
        public void setValue(Object value) {
            setText((value == null) ? "" : formatter.format(value));
        }
    }

    private static class CurrencyEditor extends DefaultCellEditor {

        private NumberFormat formatter;
        private JTextField textField;

        public CurrencyEditor(NumberFormat formatter) {
            super(new JTextField());
            this.formatter = formatter;
            this.textField = (JTextField) this.getComponent();
            textField.setHorizontalAlignment(JTextField.RIGHT);
            textField.setBorder(null);
        }

        @Override
        public Object getCellEditorValue() {
            try {
                return new Double(textField.getText());
            } catch (NumberFormatException e) {
                return Double.valueOf(0);
            }
        }

        @Override
        public Component getTableCellEditorComponent(JTable table,
            Object value, boolean isSelected, int row, int column) {
            textField.setText((value == null)
                ? "" : formatter.format((Double) value));
            return textField;
        }
    }

    private void display() {
        JFrame f = new JFrame("RenderEditNumber");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(this);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new RenderEditNumber().display();
            }
        });
    }
}