如何使用自定义的JTable单元格编辑器和单元格渲染器

Question

我已经创建了一个带有自定义表格渲染器和自定义单元格编辑器的JTable，结果如图所示

我使用一个扩展了JPanel的独立类创建了第一个表格单元中显示的面板，并将表格的值添加为：

        tbl.setCellEditor(new customCell());
        tbl.getColumnModel().getColumn(0).setCellRenderer(new customCell());

        DefaultTableModel dtm = (DefaultTableModel) tbl.getModel();

        Vector v = new Vector();
        v.add(new Panel());
        v.add("Test");
        dtm.addRow(v);

        v.clear();
        v.add(new Panel());
        v.add("Test 2");
        dtm.addRow(v);

这是我自定义的表格类来创建这个表格：

class customCell extends DefaultTableModel implements TableCellRenderer, TableCellEditor {

        public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int column) {
            Panel p = new Panel();            
            table.setRowHeight(row, p.getHeight());
            return p;
        }

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

            return new Panel();
        }

        public Object getCellEditorValue() {
            return "";
        }

        public boolean isCellEditable(EventObject anEvent) {
            throw new UnsupportedOperationException("Not supported yet.");
        }

        public boolean shouldSelectCell(EventObject anEvent) {
            return true;
        }

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

        public boolean stopCellEditing() {
            return true;
        }

        public void cancelCellEditing() {
            throw new UnsupportedOperationException("Not supported yet.");
        }

        public void addCellEditorListener(CellEditorListener l) {
            throw new UnsupportedOperationException("Not supported yet.");
        }

        public void removeCellEditorListener(CellEditorListener l) {
            throw new UnsupportedOperationException("Not supported yet.");
        }
    }

我的问题是，尽管面板显示如我所期望，但我无法输入文本字段、更改复选框或点击按钮。请告诉我如何解决这个问题。

- Harsha

Answer 1

我强烈建议重用默认表格渲染器和编辑器中提供的功能，因为您的代码存在许多问题。

1. 请将编辑器、渲染器和表格模型分开。将它们全部放在同一个类中很奇怪。
2. 对于您的渲染器，请不要每次都创建Component的新实例。相反，重用同一个组件，只需在getTableCellRendererComponent方法中修改该Component即可。
3. 对于编辑器Component也是一样。
4. 扩展默认编辑器而不是使用UnsupportedOperationException实现方法或仅返回空的String。

为了支持我的第四点，引用自JTable教程中的编辑器部分:

如果您想指定除文本字段、复选框或组合框之外的其他编辑器，则该怎么办？由于DefaultCellEditor不支持其他类型的组件，因此您需要做更多工作。您需要创建一个实现TableCellEditor接口的类。AbstractCellEditor类是一个好的超类。它实现了TableCellEditor的超接口CellEditor，为您保存了实现单元格编辑器所必需的事件触发代码。

您的单元格编辑器类需要定义至少两个方法-- getCellEditorValue和getTableCellEditorComponent。getCellEditorValue方法是由CellEditor要求的，它返回单元格的当前值。getTableCellEditorComponent方法是TableCellEditor要求的，应该配置并返回要用作编辑器的组件。

正如上面明确解释的那样，您必须实现事件触发代码：

为您保存了实现单元格编辑器所必需的事件触发代码。

而您显然忽略了这一点。因此，建议您从AbstractCellEditor开始，而不是从头实现接口。

- Robin

Answer 2

必须为已经可见的 JPanel 添加适当的 LayoutManager，Editable/non_Editable 属性。

让我们享受吧！

import java.awt.*;
import java.awt.event.*;
import java.util.EventObject;
import javax.swing.*;
import javax.swing.table.*;

public class PanelInTable {

    private JFrame frame;
    private JTable compTable = null;
    private PanelTableModel compModel = null;
    private JButton addButton = null;

    public static void main(String args[]) {
        try {
            UIManager.setLookAndFeel("com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
            //UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } catch (Exception fail) {
        }
        SwingUtilities.invokeLater(() -> {
            new PanelInTable().makeUI();
        });
    }

    public void makeUI() {
        compTable = CreateCompTable();
        JScrollPane CompTableScrollpane = new JScrollPane(compTable, 
                JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED,
                JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
        JPanel bottomPanel = CreateBottomPanel();
        frame = new JFrame("Comp Table Test");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(CompTableScrollpane, BorderLayout.CENTER);
        frame.add(bottomPanel, BorderLayout.SOUTH);
        frame.setPreferredSize(new Dimension(800, 400));
        frame.setLocation(150, 150);
        frame.pack();
        frame.setVisible(true);
    }

    public JTable CreateCompTable() {
        compModel = new PanelTableModel();
        compModel.addRow();
        JTable table = new JTable(compModel);
        table.setRowHeight(new CompCellPanel().getPreferredSize().height);
        table.setTableHeader(null);
        PanelCellEditorRenderer PanelCellEditorRenderer = new PanelCellEditorRenderer();
        table.setDefaultRenderer(Object.class, PanelCellEditorRenderer);
        table.setDefaultEditor(Object.class, PanelCellEditorRenderer);
        return table;
    }

    public JPanel CreateBottomPanel() {
        addButton = new JButton("Add Comp");
        addButton.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent ae) {
                Object source = ae.getSource();
                if (source == addButton) {
                    compModel.addRow();
                }
            }
        });
        JPanel panel = new JPanel(new GridBagLayout());
        panel.add(addButton);
        return panel;
    }
}

class PanelCellEditorRenderer extends AbstractCellEditor implements 
        TableCellRenderer, TableCellEditor {

    private static final long serialVersionUID = 1L;
    private CompCellPanel renderer = new CompCellPanel();
    private CompCellPanel editor = new CompCellPanel();

    @Override
    public Component getTableCellRendererComponent(JTable table, Object value, 
            boolean isSelected, boolean hasFocus, int row, int column) {
        renderer.setComp((Comp) value);
        return renderer;
    }

    @Override
    public Component getTableCellEditorComponent(JTable table, Object value, 
            boolean isSelected, int row, int column) {
        editor.setComp((Comp) value);
        return editor;
    }

    @Override
    public Object getCellEditorValue() {
        return editor.getComp();
    }

    @Override
    public boolean isCellEditable(EventObject anEvent) {
        return true;
    }

    @Override
    public boolean shouldSelectCell(EventObject anEvent) {
        return false;
    }
}

class PanelTableModel extends DefaultTableModel {

    private static final long serialVersionUID = 1L;

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

    public void addRow() {
        super.addRow(new Object[]{new Comp(0, 0, "", "")});
    }
}

class Comp {

    public int type;
    public int relation;
    public String lower;
    public String upper;

    public Comp(int type, int relation, String lower, String upper) {
        this.type = type;
        this.relation = relation;
        this.lower = lower;
        this.upper = upper;
    }
}

class CompCellPanel extends JPanel {

    private static final long serialVersionUID = 1L;
    private JLabel labelWith = new JLabel("With ");
    private JComboBox typeCombo = new JComboBox(new Object[]
    {"height", "length", "volume"});
    private JComboBox relationCombo = new JComboBox(new Object[]
    {"above", "below", "between"});
    private JTextField lowerField = new JTextField();
    private JLabel labelAnd = new JLabel(" and ");
    private JTextField upperField = new JTextField();
    private JButton removeButton = new JButton("remove");

   public CompCellPanel() {
        setLayout(new BoxLayout(this, BoxLayout.X_AXIS));
        relationCombo.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                enableUpper(relationCombo.getSelectedIndex() == 2);
            }
        });
        enableUpper(false);
        removeButton.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                JTable table = (JTable) SwingUtilities.getAncestorOfClass(
                        JTable.class, (Component) e.getSource());
                int row = table.getEditingRow();
                table.getCellEditor().stopCellEditing();
                ((DefaultTableModel) table.getModel()).removeRow(row);
            }
        });
        add(labelWith);
        add(typeCombo);
        add(relationCombo);
        add(lowerField);
        add(labelAnd);
        add(upperField);
        add(Box.createHorizontalStrut(100));
        add(removeButton);
    }

    private void enableUpper(boolean enable) {
        labelAnd.setEnabled(enable);
        upperField.setEnabled(enable);
    }

    public void setComp(Comp Comp) {
        typeCombo.setSelectedIndex(Comp.type);
        relationCombo.setSelectedIndex(Comp.relation);
        lowerField.setText(Comp.lower);
        upperField.setText(Comp.upper);
        enableUpper(Comp.relation == 2);
    }

    public Comp getComp() {
        return new Comp(typeCombo.getSelectedIndex(), 
                relationCombo.getSelectedIndex(), 
                lowerField.getText(), upperField.getText());
    }
}

- mKorbel

---

停止编辑应该放在编辑器中，而不是面板中。此外，在外部actionListener中搞乱模型是有争议的;-) - kleopatra

非常感谢您的发现，顺便说一下，这段代码已经被您的诚实修改了三次以上。我尝试使用Rob制作的JTable中的Action移动和使用，我认为没有更好、更简单的免费方法了。但是，没有任何变化和事件被触发，非常相似。 - mKorbel

为什么要扩展AbstractCellEditor？ - Radu Simionescu

@Radu Simionescu 因为……北极熊？:-) 我认为这是最简单、最紧凑的代码示例，适用于 SSCCE 格式，并贴在公共论坛上。 - mKorbel

请使用小写变量名称，这样很容易混淆。 - bmurauer

这个怎么样？http://stackoverflow.com/questions/40202441/how-can-i-add-custom-jcomponent-in-a-single-jtable-cell?noredirect=1#comment67670526_40202441 - partho