如何通过选择行并单击“删除”来使Swing从表中删除条目？ [英] How do I make Swing delete an entry from a table by selecting rows and clicking delete?

问题描述

我有一个面板，里面有一张桌子。该表是数据库中实体的简单视图。我希望用户能够选择条目（=行）并单击删除。

I have a panel with one table in it. The table is a simple view of entities from database. I want the user to be able to select the entries(=rows) and click delete.

我有一个扩展AbstractTableModel的表模型。

I have my own table model that extends AbstractTableModel.

我在AbstractTableModel中找不到任何方法来做这个。

I didn't find any method in AbstractTableModel to do this. Does it mean that this is not supported?

推荐答案

从表中删除行并不总是很简单，因为可以对表进行排序或过滤，这意味着您首先需要将视图行转换为模型行，然后才能从表模型中删除该行：

Delete a row(s) from a table is not always straight forward as the table could be sorted or filtered which means you first need to convert the view row to the model row before you can delete the row from the table model:

这里是一个示例

import java.awt.*;
import java.awt.event.*;
import java.util.Arrays;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javax.swing.*;
import javax.swing.table.*;

public class ItemDeletion extends JPanel
{
    private JList<String> list;
    private JTable table;

    public ItemDeletion()
    {
        setLayout( new BorderLayout(5, 5) );

        String[] items =
        {
            "One",
            "Two",
            "Three",
            "Four",
            "Five",
            "Six",
            "Seven",
            "Eight",
            "Nine",
            "Ten"
        };

        //  Add the list

        DefaultListModel<String> listModel = new DefaultListModel<String>();

        for (String item: items)
            listModel.addElement( item );

        list = new JList<String>( listModel );


        JButton listDelete = new JButton( "Delete From List" );
        listDelete.addActionListener( new ActionListener()
        {
            @Override
            public void actionPerformed(ActionEvent e)
            {
                DefaultListModel model = (DefaultListModel)list.getModel();
                int row = list.getSelectedIndex();

                while (row != -1)
                {
                    model.removeElementAt( row );
                    row = list.getSelectedIndex();
                }
            }
        });

        JPanel listPanel = new JPanel( new BorderLayout(5, 5) );
        listPanel.add(new JScrollPane( list ), BorderLayout.CENTER);
        listPanel.add(listDelete, BorderLayout.PAGE_END);

        //  Add the table

        DefaultTableModel tableModel = new DefaultTableModel(0, 1);
        List<String> tableItems = Arrays.asList( items );
        Collections.shuffle( tableItems );

        for (String item: tableItems)
        {
            System.out.println( item );
            tableModel.addRow( new String[]{item} );
        }

        table = new JTable( tableModel );

        table.setAutoCreateRowSorter(true);
        ((DefaultRowSorter)table.getRowSorter()).toggleSortOrder(0);

        JButton tableDelete = new JButton( "Delete From Table" );
        tableDelete.addActionListener( new ActionListener()
        {
            @Override
            public void actionPerformed(ActionEvent e)
            {
                DefaultTableModel model = (DefaultTableModel)table.getModel();
                int row = table.getSelectedRow();

                while (row != -1)
                {
                    int modelRow = table.convertRowIndexToModel( row );
                    model.removeRow( modelRow );
                    row = table.getSelectedRow();
                }
            }
        });

        JPanel tablePanel = new JPanel( new BorderLayout(5, 5) );
        tablePanel.add(new JScrollPane( table ), BorderLayout.CENTER);
        tablePanel.add(tableDelete, BorderLayout.PAGE_END);

        add(listPanel, BorderLayout.LINE_START);
        add(tablePanel, BorderLayout.LINE_END);
    }

    private static void createAndShowGUI()
    {
        JFrame frame = new JFrame("Multiple Item Deletion");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(new ItemDeletion(), BorderLayout.NORTH);
        frame.setLocationByPlatform( true );
        frame.pack();
        frame.setVisible( true );
    }

    public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                createAndShowGUI();
            }
        });
    }
}

这篇关于如何通过选择行并单击“删除”来使Swing从表中删除条目？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！