關於JAVA滾動條自動滾動的問題

import java.util.Hashtable;

import java.util.Vector;

import javax.swing.*;

import javax.swing.table.AbstractTableModel;

import java.awt.*;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.AdjustmentEvent;

import java.awt.event.AdjustmentListener;

public class T extends JFrame {

/**

* @param args

* @throws Exception

*/

public static void main(String[] args) throws Exception {

// TODO Auto-generated method stub

new T();

}

JButton btnA = new JButton("add");

JTable tab = new JTable();

JScrollBar bar = new JScrollBar();

JScrollPane sp = new JScrollPane(JScrollPane.VERTICAL_SCROLLBAR_NEVER,JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);

int row = 0;

Vector<Hashtable<String,String>> data = new Vector<Hashtable<String,String>>();

int page;

int totalPage;

int pageSize = 20;

int displayCount;

public T() {

super("table");

this.setSize(400,400);

this.setLayout(new BorderLayout());

this.add(btnA,BorderLayout.SOUTH);

JPanel p = new JPanel(new BorderLayout());

//p.add(sp,BorderLayout.CENTER);

//p.add(bar,BorderLayout.EAST);

bar.addAdjustmentListener(new AdjustmentListener() {

public void adjustmentValueChanged(AdjustmentEvent e) {

page = bar.getValue();

System.out.println(e.getAdjustmentType());

refresh(false);

}

});

bar.setUnitIncrement(1);

bar.setMinimum(1);

bar.setMaximum(1);

bar.setValue(1);

sp.setViewportView(tab);

//sp.setVerticalScrollBar(bar);

//sp.revalidate();

//bar.revalidate();

p.add(sp,BorderLayout.CENTER);

p.add(bar,BorderLayout.EAST);

this.add(p,BorderLayout.CENTER);

tab.setModel(new TModel());

btnA.addActionListener(new ActionListener() {

public void actionPerformed(ActionEvent e) {

Hashtable<String,String> h = new Hashtable<String,String>();

h.put("a", "aa");

h.put("b", "bb");

data.add(h);

refresh(true);

bar.setValue(page);

bar.setMaximum(totalPage);

bar.revalidate();

bar.repaint();

}

});

this.setDefaultCloseOperation(DISPOSE_ON_CLOSE);

this.setVisible(true);

}

void refresh(boolean end) {

totalPage = data.size()/pageSize;

if(data.size()%pageSize!=0)totalPage++;

if(end)page = totalPage;

displayCount = (data.size()-(page-1)*pageSize)>pageSize?pageSize:data.size()-(page-1)*pageSize;

if(page==0)displayCount = 0;

System.out.println(displayCount);

//System.out.println(data.size()+","+totalPage+","+page+","+displayCount);

tab.revalidate();

this.repaint();

}

class TModel extends AbstractTableModel {

public int getColumnCount() {

return 2;

}

public int getRowCount() {

return displayCount;

}

public Object getValueAt(int rowIndex, int columnIndex) {

int dataIndex = (page-1)*pageSize+rowIndex;

if(dataIndex>=data.size()||dataIndex<0)return null;

else {

Hashtable<String,String> h = data.get(dataIndex);

switch(columnIndex) {

case 0:return h.get("a");

case 1:return h.get("b");

default:return null;

}

}

}

}

}

不想搞了，就這樣了，因為對scrollbar的事件監聽不太懂，添加數據超過壹頁時要再添加第2個才換頁，妳看大致效果是不是妳想要的了。