import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;public class Test extends JFrame {
private int rows = 3, cols = 5;
private Object[] rowData = new Object[cols]; private DefaultTableModel model = new DefaultTableModel();
private JTable table = new JTable(model); public Test() {
for (int c = 0; c < cols; ++c)
model.addColumn("Column " + Integer.toString(c)); for (int r = 0; r < rows; ++r) {
for (int c = 0; c < cols; ++c) {
rowData[c] = "(" + r + "," + c + ")";
}
model.addRow(rowData);
}
getContentPane().add(new JScrollPane(table), BorderLayout.CENTER);
getContentPane().add(new ControlPanel(), BorderLayout.NORTH);
} public static void main(String args[]) {
Test test = new Test();
test.setBounds(100, 100, 300, 300);
test.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
test.show();
} class ControlPanel extends JPanel {
private JButton rowButton = new JButton("Add Row"),
colButton = new JButton("Add Column"); public ControlPanel() {
add(rowButton);
add(colButton); rowButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
int rowCount = model.getRowCount();
int colCount = model.getColumnCount(); if (colCount > rowData.length)
rowData = new Object[colCount]; for (int c = 0; c < colCount; ++c) {
rowData[c] = "(" + rowCount + "," +
c + ")";
}
model.addRow(rowData);
}
});
colButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
int colCount = model.getColumnCount();
model.addColumn("Column " + colCount); }
});
}
}
}
import java.awt.event.*;
import javax.swing.*;
import javax.swing.table.*;public class Test extends JFrame {
private int rows = 3, cols = 5;
private Object[] rowData = new Object[cols]; private DefaultTableModel model = new DefaultTableModel();
private JTable table = new JTable(model); public Test() {
for (int c = 0; c < cols; ++c)
model.addColumn("Column " + Integer.toString(c)); for (int r = 0; r < rows; ++r) {
for (int c = 0; c < cols; ++c) {
rowData[c] = "(" + r + "," + c + ")";
}
model.addRow(rowData);
}
getContentPane().add(new JScrollPane(table), BorderLayout.CENTER);
getContentPane().add(new ControlPanel(), BorderLayout.NORTH);
} public static void main(String args[]) {
Test test = new Test();
test.setBounds(100, 100, 300, 300);
test.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
test.show();
} class ControlPanel extends JPanel {
private JButton rowButton = new JButton("Add Row"),
colButton = new JButton("Add Column"); public ControlPanel() {
add(rowButton);
add(colButton); rowButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
int rowCount = model.getRowCount();
int colCount = model.getColumnCount(); if (colCount > rowData.length)
rowData = new Object[colCount]; for (int c = 0; c < colCount; ++c) {
rowData[c] = "(" + rowCount + "," +
c + ")";
}
model.addRow(rowData);
}
});
colButton.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
int colCount = model.getColumnCount();
model.addColumn("Column " + colCount); }
});
}
}
}
谢谢您的程序，我希望理解的是扩展DefaultTableModel的方法，还要请您继续不吝赐教。我调试了程序，发现了出错的地方
是 public int getRowCount()
{
//System.out.println("aaaaaaaaaaaaaaaa"+data.size()+"aaaaaaaaaaaaaa");
return data.size());
}
这个函数如果去掉，使用DefaultTableModel就可以正常进行，但只显示表头，
这个函数加上，则发生错误，
我查阅了资料，getColumnCount, getRowCount, getValueAt这3个Methods是AbstractTableModel从TableModel那里继承过来的，
但是DefaultTableModel是直接从Object派生出来的，没有这3个方法，那么该怎么解决这个问题呢？您有扩展DefaultTableModel的例子吗？
getRowCount()方法出错，可能是因为data为null.你直接用DefaultTableModel类试试，不用扩展了。
import javax.swing.JTable;
import javax.swing.table.DefaultTableModel;
import javax.swing.JScrollPane;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
import javax.swing.JOptionPane;
import java.awt.*;
import java.awt.event.*;public class TableDemo extends JFrame {
private boolean DEBUG = true; public TableDemo() {
super("TableDemo"); MyTableModel myModel = new MyTableModel();
JTable table = new JTable(myModel);
table.setPreferredScrollableViewportSize(new Dimension(500, 70)); //Create the scroll pane and add the table to it.
JScrollPane scrollPane = new JScrollPane(table); //Add the scroll pane to this window.
getContentPane().add(scrollPane, BorderLayout.CENTER); addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
} class MyTableModel extends DefaultTableModel {
final String[] columnNames = {"First Name",
"Last Name",
"Sport",
"# of Years",
"Vegetarian"};
final Object[][] data = {
{"Mary", "Campione",
"Snowboarding", new Integer(5), new Boolean(false)},
{"Alison", "Huml",
"Rowing", new Integer(3), new Boolean(true)},
{"Kathy", "Walrath",
"Chasing toddlers", new Integer(2), new Boolean(false)},
{"Sharon", "Zakhour",
"Speed reading", new Integer(20), new Boolean(true)},
{"Angela", "Lih",
"Teaching high school", new Integer(4), new Boolean(false)}
}; public int getColumnCount() {
return columnNames.length;
}
// public int getRowCount() {
// return data.length;
// } public String getColumnName(int col) {
return columnNames[col];
} public Object getValueAt(int row, int col) {
return data[row][col];
} /*
* JTable uses this method to determine the default renderer/
* editor for each cell. If we didn't implement this method,
* then the last column would contain text ("true"/"false"),
* rather than a check box.
*/
public Class getColumnClass(int c) {
return getValueAt(0, c).getClass();
} /*
* Don't need to implement this method unless your table's
* editable.
*/
public boolean isCellEditable(int row, int col) {
//Note that the data/cell address is constant,
//no matter where the cell appears onscreen.
if (col < 2) {
return false;
} else {
return true;
}
} /*
* Don't need to implement this method unless your table's
* data can change.
*/
public void setValueAt(Object value, int row, int col) {
if (DEBUG) {
System.out.println("Setting value at " + row + "," + col
+ " to " + value
+ " (an instance of "
+ value.getClass() + ")");
} if (data[0][col] instanceof Integer
&& !(value instanceof Integer)) {
//With JFC/Swing 1.1 and JDK 1.2, we need to create
//an Integer from the value; otherwise, the column
//switches to contain Strings. Starting with v 1.3,
//the table automatically converts value to an Integer,
//so you only need the code in the 'else' part of this
//'if' block.
//XXX: See TableEditDemo.java for a better solution!!!
try {
data[row][col] = new Integer(value.toString());
fireTableCellUpdated(row, col);
} catch (NumberFormatException e) {
JOptionPane.showMessageDialog(TableDemo.this,
"The \"" + getColumnName(col)
+ "\" column accepts only integer values.");
}
} else {
data[row][col] = value;
fireTableCellUpdated(row, col);
} if (DEBUG) {
System.out.println("New value of data:");
printDebugData();
}
} private void printDebugData() {
int numRows = getRowCount();
int numCols = getColumnCount(); for (int i=0; i < numRows; i++) {
System.out.print(" row " + i + ":");
for (int j=0; j < numCols; j++) {
System.out.print(" " + data[i][j]);
}
System.out.println();
}
System.out.println("--------------------------");
}
} public static void main(String[] args) {
TableDemo frame = new TableDemo();
frame.pack();
frame.setVisible(true);
}
}
你走的时候说了啊，直接用DefaultTableModel类，不用扩展了啊。你把那个内部类MyTableModel去掉，把里面的
String[] columnNames = {"First Name",
"Last Name",
"Sport",
"# of Years",
"Vegetarian"};
Object[][] data = {
{"Mary", "Campione",
"Snowboarding", new Integer(5), new Boolean(false)},
{"Alison", "Huml",
"Rowing", new Integer(3), new Boolean(true)},
{"Kathy", "Walrath",
"Chasing toddlers", new Integer(2), new Boolean(false)},
{"Sharon", "Zakhour",
"Speed reading", new Integer(20), new Boolean(true)},
{"Angela", "Lih",
"Teaching high school", new Integer(4), new Boolean(false)}
};移到主类中，去掉final关键字，声明DefaultTableModel时这样:
DefaultTableModel model = new DefaultTableModel(data, clomnNames);
JTable table = new JTable(model);