JTable中列的多个单元格渲染器？ [英] Multiple cell renderers for a column in a JTable?

问题描述

假设我有以下JTable，只要按下按钮就会显示：

Let's say I have the following JTable, which is displayed as soon as a button is pressed:

      | Name
------+------------
True  | Hello World
False | Foo Bar
True  | Foo
False | Bar

我想将最初的单元格渲染为JCheckBox ，以及最初为false的所有单元格都不显示任何内容（没有JCheckBox）。用户可以检查或取消检查最初为真的单元格中的JCheckBox，这对我创建的图表有效。

I want to render the cells that were initially true to a JCheckBox, and all cells that were initially false to not display anything (no JCheckBox). The user could check or un-check the JCheckBoxes in the cells that were initially true, which would do something to a chart I created.

现在，我的单元格渲染器显示JCheckBoxes在所有单元格中，包括最初为假的那些（它显示那些没有复选标记的JCheckBox），但我想不在后者中显示任何内容。这是我的代码：

Right now, my cell renderer displays JCheckBoxes in all cells, including those that were initially false (it displays those JCheckBoxes without check marks), but I want to not display anything in the latter. Here is my code:

protected class CheckBoxCellRenderer extends JCheckBox implements TableCellRenderer {

  public Component getTableCellRendererComponent(JTable table, Object value,
      boolean isSelected, boolean hasFocus, int row, int column) {
    if (!(Boolean) tableModel.getValueAt(row, 0)) {
      NoCheckBoxCellRenderer renderer = new NoCheckBoxCellRenderer();
      return renderer.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);
    }
    this.setSelected((Boolean) tableModel.getValueAt(row, 0));
    return this;
  }

}

protected class NoCheckBoxCellRenderer extends DefaultTableCellRenderer {

  public Component getTableCellRendererComponent(JTable table, Object value,
      boolean isSelected, boolean hasFocus, int row, int column) {
    this.setVisible(false);
    return this;
  }
}

在 if 声明，我尝试使用 this.setVisible（false）然后再使用 NoCheckBoxCellRenderer ，但它不是'工作。我正在考虑使用多个单元格渲染器来完成此任务。有可能这样做吗？任何建议都将不胜感激！

In the if statement, I tried using this.setVisible(false) before using NoCheckBoxCellRenderer, but it wasn't working. I'm thinking about using multiple cell renderers to accomplish this task. Would it be possible to do so? Any advice would be greatly appreciated!

推荐答案

将Boolean.TRUE存储为真值。然后为false值存储一个空String。然后，您将需要：

Store Boolean.TRUE for the true values. Then store an empty String for the false values. You will then need to:

a）覆盖getCellRenderer（...）方法，以返回单元格中找到的数据的相应渲染器。

a) override the getCellRenderer(...) method to return the appropriate renderer for the data found in the cell.

b）使包含空字符串的单元格不可编辑：

b) make the cells containing the empty string non-editable:

JTable table = new JTable(data, columnNames)
{
    public TableCellRenderer getCellRenderer(int row, int column)
    {
        if (column == 0)
        {
            Class cellClass = getValueAt(row, column).getClass();
            return getDefaultRenderer( cellClass );
        }

        return super.getCellRenderer(row, column);
    }

    public boolean isCellEditable(int row, int column)
    {
        Class cellClass = getValueAt(row, column).getClass();

        if (column == 0 && cellClass instanceof Boolean)
        {
            return true;
        }
        else
        {
            return false;
        }

        return super.isCellEditable(row, column);
    }

};

使用这种方法不需要自定义渲染器或编辑器。

Using this approach there is no need for custom renderers or editors.

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