Question

如果JTable的列为Boolean.class，则default renderer为JCheckBox。根据{{3}}选择单个单元格很容易，但也可以方便地选中所有复选框或不选中复选框。这些user selection recent在表标题中使用JCheckBox提到，但实现很尴尬且没有吸引力。如果我不需要对列进行排序，如何在examples中添加一个表现良好的控件？

附录：为方便起见，我已将JTableHeader添加为sscce，但我很乐意接受解决行为良好方面的答案问题。

Answer 1

文章How to Use Tables: Using Custom Renderers提供TableSorter作为如何检测列标题上的鼠标事件的示例。使用类似的方法，下面的示例中的SelectAllHeader extends JToggleButton和implements TableCellRenderer可以实现类似的效果。当所有复选框处于统一状态时，TableModelListener用于调节切换按钮。

enter image description here

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.*;

/**
 * @see http://stackoverflow.com/questions/7137786
 * @see http://stackoverflow.com/questions/7092219
 * @see http://stackoverflow.com/questions/7093213
 */
public class SelectAllHeaderTest {

    private static final int BOOLEAN_COL = 2;
    private static final Object colNames[] = {"Column 1", "Column 2", ""};
    private DefaultTableModel model = new DefaultTableModel(null, colNames) {

        @Override
        public Class<?> getColumnClass(int columnIndex) {
            if (columnIndex == BOOLEAN_COL) {
                return Boolean.class;
            } else {
                return String.class;
            }
        }
    };
    private JTable table = new JTable(model);

    public void create() {
        for (int x = 1; x < 6; x++) {
            model.addRow(new Object[]{
                    "Row " + x + ", Col 1", "Row " + x + ", Col 2", false
                });
        }
        table.setAutoCreateRowSorter(true);
        table.setPreferredScrollableViewportSize(new Dimension(320, 160));
        TableColumn tc = table.getColumnModel().getColumn(BOOLEAN_COL);
        tc.setHeaderRenderer(new SelectAllHeader(table, BOOLEAN_COL));
        JFrame f = new JFrame();
        f.add(new JScrollPane(table));
        f.pack();
        f.setLocationRelativeTo(null);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setVisible(true);
    }

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

            @Override
            public void run() {
                new SelectAllHeaderTest().create();
            }
        });
    }
}

/**
 * A TableCellRenderer that selects all or none of a Boolean column.
 * 
 * @param targetColumn the Boolean column to manage
 */
class SelectAllHeader extends JToggleButton implements TableCellRenderer {

    private static final String ALL = "✓ Select all";
    private static final String NONE = "✓ Select none";
    private JTable table;
    private TableModel tableModel;
    private JTableHeader header;
    private TableColumnModel tcm;
    private int targetColumn;
    private int viewColumn;

    public SelectAllHeader(JTable table, int targetColumn) {
        super(ALL);
        this.table = table;
        this.tableModel = table.getModel();
        if (tableModel.getColumnClass(targetColumn) != Boolean.class) {
            throw new IllegalArgumentException("Boolean column required.");
        }
        this.targetColumn = targetColumn;
        this.header = table.getTableHeader();
        this.tcm = table.getColumnModel();
        this.applyUI();
        this.addItemListener(new ItemHandler());
        header.addMouseListener(new MouseHandler());
        tableModel.addTableModelListener(new ModelHandler());
    }

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

    private class ItemHandler implements ItemListener {

        @Override
        public void itemStateChanged(ItemEvent e) {
            boolean state = e.getStateChange() == ItemEvent.SELECTED;
            setText((state) ? NONE : ALL);
            for (int r = 0; r < table.getRowCount(); r++) {
                table.setValueAt(state, r, viewColumn);
            }
        }
    }

    @Override
    public void updateUI() {
        super.updateUI();
        applyUI();
    }

    private void applyUI() {
        this.setFont(UIManager.getFont("TableHeader.font"));
        this.setBorder(UIManager.getBorder("TableHeader.cellBorder"));
        this.setBackground(UIManager.getColor("TableHeader.background"));
        this.setForeground(UIManager.getColor("TableHeader.foreground"));
    }

    private class MouseHandler extends MouseAdapter {

        @Override
        public void mouseClicked(MouseEvent e) {
            viewColumn = header.columnAtPoint(e.getPoint());
            int modelColumn = tcm.getColumn(viewColumn).getModelIndex();
            if (modelColumn == targetColumn) {
                doClick();
            }
        }
    }

    private class ModelHandler implements TableModelListener {

        @Override
        public void tableChanged(TableModelEvent e) {
            if (needsToggle()) {
                doClick();
                header.repaint();
            }
        }
    }

    // Return true if this toggle needs to match the model.
    private boolean needsToggle() {
        boolean allTrue = true;
        boolean allFalse = true;
        for (int r = 0; r < tableModel.getRowCount(); r++) {
            boolean b = (Boolean) tableModel.getValueAt(r, targetColumn);
            allTrue &= b;
            allFalse &= !b;
        }
        return allTrue && !isSelected() || allFalse && isSelected();
    }
}

Answer 2

问题分为两部分（我认为： - ）

可用性：发明UI交互/元素容易使用户感到困惑。没有特别的顺序：

列标题标题用于描述列的内容，在用动作描述替换它时内容描述会丢失
它不是立即（对我来说，地球上最愚蠢的用户 :-)清楚标题单元格具有切换按钮的功能。意外点击它将会丢失该列中所有早期的内容状态

因此，即使交互分析出现明确的我们需要/想要它，

仅在内容
使用更清晰的小部件（例如，三态复选框all-de- / selected，混合内容）。此外，必须从混合内容中进行去/选择。在第二个想法，一个复选框可能也不是最好的选择，没有深入挖掘
最大限度地减少意外（仅适合我:-)的可能性，从“普通标题”区域更改批量状态（例如，通过活动区域的清晰视觉分离 - 复选框图标）。

技术方面

TableHeader不适用于“实时”组件。无论需要什么都必须由我们自己控制
示例（例如JIDE网格支持添加组件）
摆弄标题往往看起来没有吸引力，因为改变渲染器并同时保持LAF提供的外观并不容易。

Answer 3

enter image description here

使用自定义TableCellRenderer：

localStorage

请注意，带有弹出菜单（例如JComboBox或JMenu）的组件不能正常工作。见：Docs here）。但您可以在TableHeader中使用JComboBox fails to expand in JTable TableHeader：

enter image description here

    // column 1
    col = table.getColumnModel().getColumn(1);
    col.setHeaderRenderer(new EditableHeaderRenderer( new JButton("Button")));
    // column 2     
    col = table.getColumnModel().getColumn(2);
    col.setHeaderRenderer(new EditableHeaderRenderer( new JToggleButton("Toggle")));
    // column 3
    col = table.getColumnModel().getColumn(3);
    col.setHeaderRenderer(new EditableHeaderRenderer( new JCheckBox("CheckBox")));



class EditableHeaderRenderer implements TableCellRenderer {

    private JTable table = null;
    private MouseEventReposter reporter = null;
    private JComponent editor;

    EditableHeaderRenderer(JComponent editor) {
        this.editor = editor;
        this.editor.setBorder(UIManager.getBorder("TableHeader.cellBorder"));
    }

    @Override
    public Component getTableCellRendererComponent(JTable table, Object value, boolean isSelected, boolean hasFocus, int row, int col) {
        if (table != null && this.table != table) {
            this.table = table;
            final JTableHeader header = table.getTableHeader();   
            if (header != null) {   
                this.editor.setForeground(header.getForeground());   
                this.editor.setBackground(header.getBackground());   
                this.editor.setFont(header.getFont());
                reporter = new MouseEventReposter(header, col, this.editor);
                header.addMouseListener(reporter);
            }
        }

        if (reporter != null) reporter.setColumn(col);

        return this.editor;
    }

    static public class MouseEventReposter extends MouseAdapter {

        private Component dispatchComponent;
        private JTableHeader header;
        private int column  = -1;
        private Component editor;

        public MouseEventReposter(JTableHeader header, int column, Component editor) {
            this.header = header;
            this.column = column;
            this.editor = editor;
        }

        public void setColumn(int column) {
            this.column = column;
        }

        private void setDispatchComponent(MouseEvent e) {
            int col = header.getTable().columnAtPoint(e.getPoint());
            if (col != column || col == -1) return;

            Point p = e.getPoint();
            Point p2 = SwingUtilities.convertPoint(header, p, editor);
            dispatchComponent = SwingUtilities.getDeepestComponentAt(editor, p2.x, p2.y);
        }

        private boolean repostEvent(MouseEvent e) {
            if (dispatchComponent == null) {
                return false;
            }
            MouseEvent e2 = SwingUtilities.convertMouseEvent(header, e, dispatchComponent);
            dispatchComponent.dispatchEvent(e2);
            return true;
        }

        @Override
        public void mousePressed(MouseEvent e) {
            if (header.getResizingColumn() == null) {
                Point p = e.getPoint();

                int col = header.getTable().columnAtPoint(p);
                if (col != column || col == -1) return;

                int index = header.getColumnModel().getColumnIndexAtX(p.x);
                if (index == -1) return;

                editor.setBounds(header.getHeaderRect(index));
                header.add(editor);
                editor.validate();
                setDispatchComponent(e);
                repostEvent(e);
            }
        }

        @Override
        public void mouseReleased(MouseEvent e) {
            repostEvent(e);
            dispatchComponent = null;
            header.remove(editor);
        }
    }
}

如何将控件放在JTable的JTableHeader中？

3 个答案: