使用JPopupMenu的JTable

Question

如何防止触发并JPopupMenu仅Mouse Cursor在选中时显示JTable'Row

我的问题:如果有另一种方式,getBounds从选定的行,并确定/比较与Mouse位置...

我简单的sscce演示了不想要的相反状态,任何行都可以选择并JPopupMenu从整体触发JTable

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

你在寻找这样的东西吗？

仅显示所选行的弹出窗口

  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());
        }
     }
  }

或者相反,为了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());
        }
     }

Answer 2

这是一个有趣的问题,因为它突出了JComponent上缺少的api :-)

众所周知,注册popupMenus的推荐方法是使用componentPopupMenu属性.相关的api是

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

缺少什么(实际上需要这个要求)是

JPopupMenu getComponentPopupMenu(MouseEvent);

这个缺点更令人烦恼,因为在 getComponentPopup()之后调用了getPopupLocation(由LAF深处的AWTEventHelper ).因此,存储没有余地,例如存储可能触发弹出窗口的最后一个鼠标事件,然后决定哪个/是否返回弹出窗口.并且为该位置返回null将仅导致在鼠标位置显示它

唯一(脏)黑客(我完全不愿意弄脏MouseListener ;-)是覆盖getComponentPopup并决定是否根据当前鼠标位置返回它

    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();
        }

    };

副作用是弹出显示不是由键盘触发,只要鼠标位于表格上方的任何位置,这可能是或不是问题.