在单元格编辑器中调用操作后，单元格不会更新

Question

我使用带有单元格渲染器的表格，它允许我在每个单元格中放置一个带有值的按钮“x”，以便我可以通过按按钮删除单元格的值。单元格编辑器将操作侦听器分配给按钮，并在按下按钮时调用适当的操作。

作为 DefaultTableModel 的表模型中的每一列都由值的数组列表填充。我成功地通过按下按钮从数组列表中删除了正确的值，并且表中的每个其他单元格在更改后都会刷新，但被删除的值的单元格保持不变。如果我重新启动应用程序或向数组列表添加一个值，表将按预期刷新，并且一切看起来都应有的样子。

那么问题是，单元格渲染器似乎不会忘记单元格的初始值，因此即使重新绘制表格，仍然会继续将该值打印到单元格中。有谁知道我如何正确刷新表格以便正确显示值？

表格类：

public class Table extends JTable {

public static DefaultTableModel model = new DefaultTableModel();
private Days d;
private JFrame frame;
private AddCellRenderer renderer;
private AddCellEditor editor;

public Table(Days d, JFrame frame) {
    // Assign the table model to the table
    super(model);
    this.d = d;
    this.frame = frame;

    // Define dimensions of table
    model.setRowCount(11);
    model.setColumnCount(5);

    // Block resizing and reordering of headers
    this.setColumnSelectionAllowed(false);
    this.setRowSelectionAllowed(false);
    this.setCellSelectionEnabled(true);
    this.setTableHeader(null);

    // Define first row height
    this.setRowHeight(38);
    // Define all other row's heights
    this.setRowHeight(0, 45);

    this.d.setTable(this);

    for (int i = 0; i < 5; i++) {
        editor = new AddCellEditor(new JCheckBox(), d.getVisibleDays().get(i), this);
        renderer = new AddCellRenderer(d.getVisibleDays().get(i), editor);
        this.getColumnModel().getColumn(i).setCellRenderer(renderer);
        this.getColumnModel().getColumn(i).setCellEditor(editor);
    }

    this.refresh();
}

public void refresh() {

    // Empty table
    for (int i = 0; i < 5; i++) {
        for (int j = 0; j < 11; j++) {
            this.getModel().setValueAt(null, j, i);
        }
    }

    // Populate table with entries for each day
    for (int i = 0; i < 5; i++) {

        Iterator<String> iterator = d.getVisibleDays().get(i).getEntryListIterator();

        int j = 0;

        while(iterator.hasNext()){
            String s = iterator.next();
            this.getModel().setValueAt(s, (j+1), i);
            j++;
        }

        this.getModel().setValueAt(d.getVisibleDays().get(i).getDayName(), 0, i);
    }
}

public void modelClearValueAt(int row, int column) {
    this.getModel().setValueAt(null, row, column);
}
}

单元格编辑器类：

public class AddCellEditor extends DefaultCellEditor {

private JPanel headerPanel;
private JPanel entryPanel;
private JLabel dayName;
private JLabel entryValue;
protected JButton addButton;
private JButton removeButton;
private String label;
private int row;
private int column;
private Day day;
private String date;
private Table table;
private AddCellRenderer renderer;

public AddCellEditor(JCheckBox checkBox, Day day, Table table) {
    super(checkBox);
    this.day = day;
    this.table = table;
    date = day.getDayDate();
    headerPanel = new JPanel();
    headerPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
    entryPanel = new JPanel();
    entryPanel.setLayout(new FlowLayout(FlowLayout.LEFT));
    dayName = new JLabel();
    entryValue = new JLabel();
    addButton = new JButton();
    removeButton = new JButton();
    headerPanel.add(dayName);
    headerPanel.add(addButton);
    entryPanel.add(entryValue);
    entryPanel.add(removeButton);
    addButton.setOpaque(true);
    addButton.setPreferredSize(new Dimension(16, 16));
    removeButton.setOpaque(true);
    removeButton.setPreferredSize(new Dimension(16, 16));
    addButton.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            System.out.println("Add pressed");
            addItem();
            fireEditingStopped();
        }
    });
    removeButton.addActionListener(new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            System.out.println("Remove pressed");
            removeItem();
            getTable().refresh();
            fireEditingStopped();
        }
    });

}

public void setRenderer(AddCellRenderer renderer) {
    this.renderer = renderer;
}

public Component getTableCellEditorComponent(JTable table, 
        Object value, boolean isSelected, int row, int column) {

    this.row = row;
    this.column = column;

    if (row == 0) {
         return this.headerPanel;
    }
    if (row != 0 && value != null) {
        return this.entryPanel;
    }
    return null;
}

public void addItem() {
    String input = JOptionPane.showInputDialog("Add entry for " + label + ":");

    if ((input != null) && (input.length() > 0)) {
        System.out.println("Added: " + input + "Item");
        day.addEntry(input, column);
    }
}

public void removeItem() {
    table.modelClearValueAt(row, column);
    day.removeEntry(row-1);
    System.out.println("Item removed");
}

public Table getTable() {
    return this.table;
}

public boolean stopCellEditing() {
    return super.stopCellEditing();
}

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

提前致谢

Answer 1

好吧，无法抗拒（另一种方法是擦洗浴室:-)

下面是一个非常原始的大纲（足以给您一个想法），说明如何使用行为良好的编辑器和自定义 tableModel 来解决您的目标。

• MyTableModel 是一个自定义实现，基本上由任意条目列表支持，
• 该 tableModel 支持删除/添加项目。目前是私下的，所以您不会想从编辑器中调用它们:-)它们足够安全，可以在需要时在公共范围内公开，如果程序的其他部分需要修改条目，并且
• 模型可以处理不同的条目setValueAt 中的值类型：修改标记、NewEntry 或普通值
• 自定义编辑器是一个带有删除、添加行按钮的面板。
• 按钮的操作在根据需要调用编辑停止/取消之前设置适当的 editorValue

模型：

public static class MyTableModel extends AbstractTableModel {

    public enum Modify {
        ADD,
        REMOVE
    }

    public static class NewItem {
        public final Object entry;

        public NewItem(Object entry) {
            this.entry = entry;
        }
    }

    private List entries;

    public MyTableModel(List entries) {
        this.entries = entries;
    }

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

    @Override
    public int getColumnCount() {
        return 1;
    }


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

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

    @Override
    public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
        if (aValue instanceof NewItem) {
            addEntry(((NewItem) aValue).entry);
        } else if (Modify.REMOVE == aValue) {
            removeEntry(rowIndex);
        } else {
            entries.set(rowIndex, aValue);
        }    
    }

    private void removeEntry(int rowIndex) {
        entries.remove(rowIndex);
        fireTableRowsDeleted(rowIndex, rowIndex);
    }

    private void addEntry(Object aValue) {
        int last = getRowCount();
        entries.add(aValue);
        fireTableRowsInserted(last, last);
    }


}

编辑器：

public static class MyCellEditor extends AbstractCellEditor implements TableCellEditor {

    private Object editorValue;
    private JLabel entryView;
    JComponent editor;

    public MyCellEditor() {
        editor = new JPanel();
        entryView = new JLabel();
        editor.add(entryView);
        Action add = createAddAction();
        editor.add(new JButton(add));
        Action remove = createRemoveAction();
        editor.add(new JButton(remove));
    }

    public Action createRemoveAction() {
        Action remove = new AbstractAction("Remove Entry") {

            @Override
            public void actionPerformed(ActionEvent e) {
                editorValue = MyTableModel.Modify.REMOVE;
                fireEditingStopped();
            }

        };
        return remove;
    }

    public Action createAddAction() {
        Action add = new AbstractAction("Add Entry") {

            @Override
            public void actionPerformed(ActionEvent e) {
                String input = JOptionPane.showInputDialog("Add entry: ");

                if ((input != null) && (input.length() > 0)) {
                    editorValue = new MyTableModel.NewItem(input);
                    fireEditingStopped();
                } else {
                    fireEditingCanceled();
                }

            }

        };
        return add;
    }

    @Override
    public Object getCellEditorValue() {
        return editorValue;
    }

    @Override
    public Component getTableCellEditorComponent(JTable table,
            Object value, boolean isSelected, int row, int column) {
        entryView.setText(value != null ? value.toString() : "");
        return editor;
    }


}

用法：

    List entries = new ArrayList();
    for (int i = 0; i < 5; i++) {
        entries.add("entry " + i);
    }
    TableModel model = new MyTableModel(entries);
    JTable table = new JTable(model);
    table.getColumnModel().getColumn(0).setCellEditor(new MyCellEditor());
    table.getColumnModel().getColumn(0).setPreferredWidth(200);
    table.setRowHeight(50);

Answer 2

如果您使用的是 DefaultTableModel，则必须删除模型本身保存的值，而不是删除用于构建模型的 ArrayList 中的值。您可以通过调用 DefaultTableModel 对象的 setValueAt(...) 方法来完成此操作。

您可能希望发布 SSCCE 以获得更具体的帮助。