如果我從數據庫中獲取記錄，如何添加復選框

Question

1. 當我從數據庫中獲取記錄時，我想在記錄的前面添加復選框。請檢查我的代碼，您會自動知道我想要什么

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1. 類名稱：-AddAccountDao.Java

     public class AddAccountDao { public static List<AddAccount> view(){ List <AddAccount> list=new ArrayList<>(); try{ Connection con=getCon(); PreparedStatement pst=con.prepareStatement("SELECT * FROM adminaccount"); ResultSet rst=pst.executeQuery(); while(rst.next()){ AddAccount ad=new AddAccount(); ad.setId(rst.getInt(1)); ad.setName(rst.getString(2)); ad.setPassword(rst.getString(3)); ad.setEmail(rst.getString(4)); ad.setContact(rst.getString(5)); list.add(ad); } con.close(); } catch(Exception e){ System.out.println(e); } return list; } } 

2. 類名稱：-AdminViewAccount

     public class AdminViewAccount extends JFrame{ static AdminViewAccount frame; public AdminViewAccount(){ List<AddAccount> list=AddAccountDao.view(); int size=list.size(); String data[][]=new String[size][6]; int row=0; for(AddAccount ad:list){ data[row][1]=String.valueOf(ad.getId()); data[row][2]=ad.getName(); data[row][3]=ad.getPassword(); data[row][4]=ad.getEmail(); data[row][5]=ad.getContact(); row++; } String columnName[]= {"Select","ID","Name","Password","Email","Contact No."}; JTable t=new JTable(data,columnName); JScrollPane sp=new JScrollPane(t); add(sp); setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); setBounds(100,100,800,400); } public static void main(String[] args) { EventQueue.invokeLater(new Runnable(){ @Override public void run() { try{ frame=new AdminViewAccount(); frame.setVisible(true); } catch(Exception e){ e.printStackTrace(); } } }); } } 

3. 類名稱：-AddAccount

    public class AddAccount { private int id; private String name,password,email,contact; public AddAccount(){} public AddAccount(String name,String password,String email,String contact){ super(); this.name=name; this.password=password; this.email=email; this.contact=contact; } public void setId(int id){ this.id=id; } public int getId(){ return id; } public void setName(String name){ this.name=name; } public String getName(){ return name; } public void setPassword(String password){ this.password=password; } public String getPassword(){ return password; } public void setEmail(String email){ this.email=email; } public String getEmail(){ return email; } public void setContact(String contact){ this.contact=contact; } public String getContact(){ return contact; } } 

Answer 1

一種方法是創建一個使用TableModel的自定義TableModel，並在表的開頭添加一個復選框列：

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

public class CheckBoxWrapperTableModel extends AbstractTableModel
{
    private ArrayList<Boolean> checkBoxes = new ArrayList<>();

    private DefaultTableModel model;
    private String columnName;

    public CheckBoxWrapperTableModel(DefaultTableModel model, String columnName)
    {
        this.model = model;
        this.columnName = columnName;

        for (int i = 0; i < model.getRowCount(); i++)
            checkBoxes.add( Boolean.FALSE );
    }

    @Override
    public String getColumnName(int column)
    {
        return (column > 0) ? model.getColumnName(column - 1) : columnName;
    }

    @Override
    public int getRowCount()
    {
        return model.getRowCount();
    }

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

    @Override
    public Object getValueAt(int row, int column)
    {
        if (column > 0)
            return model.getValueAt(row, column - 1);
        else
        {
            Object value = checkBoxes.get(row);
            return (value == null) ? Boolean.FALSE : value;
        }
    }

    @Override
    public boolean isCellEditable(int row, int column)
    {
        if (column > 0)
            return model.isCellEditable(row, column - 1);
        else
            return true;
    }

    @Override
    public void setValueAt(Object value, int row, int column)
    {
        if (column > 0)
            model.setValueAt(value, row, column - 1);
        else
        {
            checkBoxes.set(row, (Boolean)value);
        }

        fireTableCellUpdated(row, column);
    }

    @Override
    public Class getColumnClass(int column)
    {
        return (column > 0) ? model.getColumnClass(column - 1) : Boolean.class;
    }

    public void removeRow(int row)
    {
        checkBoxes.remove(row);
        fireTableRowsDeleted(row, row);
        model.removeRow(row);
    }

    private static void createAndShowGUI()
    {
        //  Create the table with check marks in the first column

        DefaultTableModel model = new DefaultTableModel(5, 1);

        for (int i = 0; i < model.getRowCount(); i++)
        {
            model.setValueAt("" + i, i, 0);
        }

        CheckBoxWrapperTableModel wrapperModel = new CheckBoxWrapperTableModel(model, "Select");
        JTable table = new JTable(wrapperModel);

        //  Add button to delete selected rows

        JButton button = new JButton( "Delete Selected Rows" );
        button.addActionListener( new ActionListener()
        {
            @Override
            public void actionPerformed(ActionEvent e)
            {
                for (int i = table.getRowCount() - 1; i >= 0; i--)
                {
                    Boolean selected = (Boolean)table.getValueAt(i, 0);
                    System.out.println(selected + " : " + i);

                    if (selected)
                    {
                        wrapperModel.removeRow(i);
                    }

                }
            }
        });

        JFrame frame = new JFrame("SSCCE");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add( new JScrollPane( table ) );
        frame.add( button, BorderLayout.PAGE_END );
        frame.pack();
        frame.setLocationByPlatform( true );
        frame.setVisible( true );
    }

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

或另一種方法，因為您只是將數據復制到TableModel中，所以只需在復制數據時添加一個額外的列即可：

data[row][0] = Boolean.FALSE; // added
data[row][1]=String.valueOf(ad.getId());

然后，您還需要重寫TableModel的getColumnClass(...)方法以為第一列返回Boolean.class ，如上面的TableModel中所示。