使用JPopupMenu的JTable

Question

如何防止仅当在选定的JPopupMenu上使用Mouse Cursor时才触发和显示JTable'Row

我的问题是:如果有另一种方法作为getBounds从选定的行，并确定/比较它与Mouse位置...

我的简单sscce演示了不想要的相反状态，可以选择任何行，并且从整个JTable触发JPopupMenu

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

public class TableCheckBox extends JFrame {

    private static final long serialVersionUID = 1L;
    private JTable table;

    public TableCheckBox() {
        Object[] columnNames = {"Type", "Company", "Shares", "Price", "Boolean"};
        Object[][] data = {
            {"Buy", "IBM", new Integer(1000), new Double(80.50), false},
            {"Sell", "MicroSoft", new Integer(2000), new Double(6.25), true},
            {"Sell", "Apple", new Integer(3000), new Double(7.35), true},
            {"Buy", "Nortel", new Integer(4000), new Double(20.00), false}
        };
        DefaultTableModel model = new DefaultTableModel(data, columnNames);
        table = new JTable(model) {

            private static final long serialVersionUID = 1L;

            @Override
            public Class getColumnClass(int column) {
                return getValueAt(0, column).getClass();
            }
        };
        table.setPreferredScrollableViewportSize(table.getPreferredSize());
        JScrollPane scrollPane = new JScrollPane(table);
        add(scrollPane);
        createPopupMenu();
    }

    private void createPopupMenu() {
        JPopupMenu popup = new JPopupMenu();
        JMenuItem myMenuItem1 = new JMenuItem("cccccccccccccccccccccc");
        JMenuItem myMenuItem2 = new JMenuItem("bbbbbbbbbbbbbbbbbbbbbb");
        popup.add(myMenuItem1);
        popup.add(myMenuItem2);
        MouseListener popupListener = new PopupListener(popup);
        table.addMouseListener(popupListener);
    }

    private class PopupListener extends MouseAdapter {

        private JPopupMenu popup;

        PopupListener(JPopupMenu popupMenu) {
            popup = popupMenu;
        }

        @Override
        public void mousePressed(MouseEvent e) {
            maybeShowPopup(e);
        }

        @Override
        public void mouseReleased(MouseEvent e) {
            if (table.getSelectedRow() != -1) {
                maybeShowPopup(e);
            }
        }

        private void maybeShowPopup(MouseEvent e) {
            if (e.isPopupTrigger()) {
                popup.show(e.getComponent(), e.getX(), e.getY());
            }
        }
    }

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

            @Override
            public void run() {
                TableCheckBox frame = new TableCheckBox();
                frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
                frame.pack();
                frame.setLocation(150, 150);
                frame.setVisible(true);
            }
        });
    }
}

Answer 1

这是一个有趣的问题，因为它突出显示了JComponent上缺少的api :-)

众所周知，注册popupMenus的推荐方式是使用componentPopupMenu属性。相关接口为

 void setComponentPopupMenu(JPopupMenu);
 JPopupMenu getComponentPopupMenu();
 Point getPopupLocation(MouseEvent);

缺少的(也是这个需求实际需要的)是

JPopupMenu getComponentPopupMenu(MouseEvent);

这种缺失更让人恼火，因为getPopupLocation是在getComponentPopup()之后调用的(由LAF中的AWTEventHelper调用)。因此，对于类似于存储可能触发弹出窗口的最后一个鼠标事件，然后再决定返回哪一个/是否返回弹出窗口这样的黑客行为，是没有回旋余地的。，并且为该位置返回null只会导致在鼠标位置显示该位置。

唯一的(肮脏的)技巧(除了我非常不愿意使用MouseListener ;-)是覆盖getComponentPopup，并根据当前鼠标位置决定是否返回它

    table = new JTable(model) {

        /** 
         * @inherited <p>
         */
        @Override
        public JPopupMenu getComponentPopupMenu() {
            Point p = getMousePosition();
            // mouse over table and valid row
            if (p != null && rowAtPoint(p) >= 0) {
                // condition for showing popup triggered by mouse
                if (isRowSelected(rowAtPoint(p))) {
                    return super.getComponentPopupMenu();
                } else {
                    return null;
                }
            }
            return super.getComponentPopupMenu();
        }

    };

副作用是，只要鼠标位于桌面上方，弹出窗口就不会被键盘触发，这可能是个问题，也可能不是问题。

Answer 2

你是在找这样的东西吗？

仅在选定行上显示弹出窗口

  private void maybeShowPopup(MouseEvent e) {
     if (e.isPopupTrigger()) {

        // get row that pointer is over
        int row = table.rowAtPoint(e.getPoint());

        // if pointer is over a selected row, show popup
        if (table.isRowSelected(row)) {
           popup.show(e.getComponent(), e.getX(), e.getY());
        }
     }
  }

反之亦然，以防止弹出窗口仅显示在选定的行上：

  private void maybeShowPopup(MouseEvent e) {
     if (e.isPopupTrigger()) {
        int row = table.rowAtPoint(e.getPoint());
        int[] selectedRows = table.getSelectedRows();

        if (!table.isRowSelected(row)) {
           popup.show(e.getComponent(), e.getX(), e.getY());
        }
     }