如何刷新 JTable 中的数据我正在使用 TableModel

Hi,

我已经创建了 TableModel，并希望在添加新行后刷新 JTable。应该向监听器添加什么来“刷新”JTable？

public class MyTableModel implements TableModel  {
    private Set<TableModelListener> listeners = new HashSet<TableModelListener>();

    //List<Staff> staffs = Factory.getInstance().getStaffDAO().getAllStaff();
    private List<Staff> staffs;

    public MyTableModel(List<Staff> staffs){
        this.staffs = staffs;
    }

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

    @Override
    public int getColumnCount() {
        return 5;  
    }

    @Override
    public String getColumnName(int columnIndex) {
        switch (columnIndex){
            case 0:
                return "First Name";
            case 1:
                return "Second Name";
            case 2:
                return "Date";
            case 3:
                return "Position";
            case 4:
                return "Salary";
        }
        return "";  
    }

    @Override
    public Class<?> getColumnClass(int columnIndex) {
        return Object.class;  
    }

    @Override
    public boolean isCellEditable(int rowIndex, int columnIndex) {
        return true;  
    }

    @Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        Staff staff = staffs.get(rowIndex);
        switch (columnIndex){
            case 0:
                return staff.getName();
            case 1:
                return staff.getSurname();
            case 2:
                return staff.getDate();
            case 3:
                return staff.getPosition();
            case 4:
                return staff.getSalary();
        }
        return "";  
    }

    @Override
    public void setValueAt(Object aValue, int rowIndex, int columnIndex) {
    }

    @Override
    public void addTableModelListener(TableModelListener l) {
    }

    @Override
    public void removeTableModelListener(TableModelListener l) {
    }
}

这是我的添加行按钮的监听器：

 @Override
    public void actionPerformed(ActionEvent e) {
        Staff staff = new Staff();
        staff.setName(JOptionPane.showInputDialog("Enter First Name"));
        staff.setSurname(JOptionPane.showInputDialog("Enter Second Name"));
        staff.setDate(JOptionPane.showInputDialog("Enter Date"));
        staff.setPosition(JOptionPane.showInputDialog("Enter Position"));
        staff.setSalary(JOptionPane.showInputDialog("Enter Salary"));
        try {
            Factory.getInstance().getStaffDAO().addStaff(staff);
        } catch (SQLException e1) {
            e1.printStackTrace();  
        }
!!!Here should be some code that will be firing my table after adding new row!!!
}

我尝试在我的actionPerformed()中使用AbstractTableModel的firetabledatachanged()方法，但不幸的是，出现了ClassCastException。

UPDATE 1

WorkPlaceGui.java

public class WorkPlaceGui extends JFrame implements ActionListener {

    AbstractTableModel model;
    JTable jTable;
    JScrollPane jScrollPane;

    public WorkPlaceGui()throws SQLException{


        List<Staff> staffs = Factory.getInstance().getStaffDAO().getAllStaff();
        for(int i = 0; i < 0; i++) {
                staffs.add(new Staff("First Name " + staffs.get(i).getName(), "Second Name " + staffs.get(i).getSurname(), "Date " + staffs.get(i).getDate(), "Position " + staffs.get(i).getPosition(), "Salary " + staffs.get(i).getSalary()));
        }

        model = new MyTableModel(staffs);
        jTable = new JTable(model);
        JButton jBtnAdd = new JButton("Добавить");
        JButton jBtnDel = new JButton("Удалить");
        JButton jBtnUpd = new JButton("Обновить");
        JButton jBtnAdmin = new JButton("Админка");
        JPanel panelNorth = new JPanel();
        JPanel panelCenter = new JPanel();
        JPanel panelSouth = new JPanel();
        jTable.setPreferredScrollableViewportSize(new Dimension(350, 150));
        jScrollPane = new JScrollPane(jTable);


        panelNorth.setLayout(new FlowLayout());
        panelNorth.add(jBtnAdd);
        panelNorth.add(jBtnDel);
        panelNorth.add(jBtnUpd);
        panelNorth.add(jBtnAdmin);
        panelCenter.add(jScrollPane);

        setLayout(new BorderLayout());
        add(panelNorth, BorderLayout.NORTH);
        add(panelCenter, BorderLayout.CENTER);

        jBtnAdd.addActionListener(this);

        setPreferredSize(new Dimension(550, 300));
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setTitle("Staff data base");
        pack();
        setVisible(true);
        setLocationRelativeTo(null);
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        Staff staff = new Staff();
        staff.setName(JOptionPane.showInputDialog("Enter First Name"));
        staff.setSurname(JOptionPane.showInputDialog("Enter Second Name"));
        staff.setDate(JOptionPane.showInputDialog("Enter Date"));
        staff.setPosition(JOptionPane.showInputDialog("Enter Position"));
        staff.setSalary(JOptionPane.showInputDialog("Enter Salary"));
        try {
            Factory.getInstance().getStaffDAO().addStaff(staff);
        } catch (SQLException e1) {
            e1.printStackTrace();
        }
        model.fireTableDataChanged();
    }
}

MyTableModel.java

public class MyTableModel extends AbstractTableModel {

    private List<Staff> staffs;

    public MyTableModel(List<Staff> staffs){
        this.staffs = staffs;
    }

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

    @Override
    public int getColumnCount() {
        return 5;
    }

    @Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        Staff staff = staffs.get(rowIndex);
        switch (columnIndex){
            case 0:
                return staff.getName();
            case 1:
                return staff.getSurname();
            case 2:
                return staff.getDate();
            case 3:
                return staff.getPosition();
            case 4:
                return staff.getSalary();
        }
        return "";
    }
}

你已经用艰难的方式做到了。

首先，您直接从TableModel其次，您未能实现侦听器的要求......

相反，尝试从AbstractTableModel http://docs.oracle.com/javase/7/docs/api/javax/swing/table/AbstractTableModel.html相反，它已经包含监听器注册和通知的实现。

您需要提供一种方法，允许您向表模型添加行。在此方法中，您需要使用fireTableRowsInserted http://docs.oracle.com/javase/7/docs/api/javax/swing/table/AbstractTableModel.html#fireTableRowsInserted%28int,%20int%29方法将通知使用该模型的任何表，已添加新行...

更新示例

这是非常非常基本的例子。它的唯一目的是演示使用fireTableRowsInserted。它使用了 SwingTimer每 125 毫秒添加一个新行，直到您杀死它；）

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.AbstractTableModel;

public class DynamicTable {

    public static void main(String[] args) {
        new DynamicTable();
    }

    public DynamicTable() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
                }
                
                final MyTableModel model = new MyTableModel();
                JTable table = new JTable(model);
                
                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new JScrollPane(table));
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
                
                Timer timer = new Timer(125, new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        model.addRow();
                    }
                });
                timer.start();
            }
        });
    }
    
    public class MyTableModel extends AbstractTableModel {

        private List<String[]> rows;

        public MyTableModel() {
            rows = new ArrayList<>(25);
        }
        
        @Override
        public int getRowCount() {
            return rows.size();
        }

        @Override
        public int getColumnCount() {
            return 4;
        }

        @Override
        public Class<?> getColumnClass(int columnIndex) {
            return String.class;
        }

        @Override
        public Object getValueAt(int rowIndex, int columnIndex) {
            String[] row = rows.get(rowIndex);
            return row[columnIndex];
        }
        
        public void addRow() {
            int rowCount = getRowCount();
            String[] row = new String[getColumnCount()];
            for (int index = 0; index < getColumnCount(); index++) {
                row[index] = rowCount + "x" + index;
            }
            rows.add(row);
            fireTableRowsInserted(rowCount, rowCount);
        }            
    }                    
}

更新了另一个例子

因为你的表模型有它自己的支持List，它与您的工厂没有任何联系。它不知道您何时向其中添加或删除对象。这意味着您将负责更新模型：

public class MyTableModel extends AbstractTableModel {

    private List<Staff> staffs;

    public MyTableModel(List<Staff> staffs){
        this.staffs = staffs;
    }

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

    @Override
    public int getColumnCount() {
        return 5;
    }
    
    public void add(Staff staff) {
        int size = getSize();
        staffs.add(staff);
        fireTableRowsInserted(size, size);
    }

    public void remove(Staff staff) {
        if (staffs.contains(staff) {
            int index = stafff.indexOf(staff);
            staffs.remove(staff);
            fireTableRowsDeleted(index, index);
        }
    }

    @Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        Staff staff = staffs.get(rowIndex);
        switch (columnIndex){
            case 0:
                return staff.getName();
            case 1:
                return staff.getSurname();
            case 2:
                return staff.getDate();
            case 3:
                return staff.getPosition();
            case 4:
                return staff.getSalary();
        }
        return "";
    }
}

和你的actionPerformed:

@Override
public void actionPerformed(ActionEvent e) {
    Staff staff = new Staff();
    staff.setName(JOptionPane.showInputDialog("Enter First Name"));
    staff.setSurname(JOptionPane.showInputDialog("Enter Second Name"));
    staff.setDate(JOptionPane.showInputDialog("Enter Date"));
    staff.setPosition(JOptionPane.showInputDialog("Enter Position"));
    staff.setSalary(JOptionPane.showInputDialog("Enter Salary"));
    try {
        Factory.getInstance().getStaffDAO().addStaff(staff);
        ((MyTableModel)model).add(staff);
    } catch (SQLException e1) {
        e1.printStackTrace();  
    }
}