我对摇摆有点新意，而我正试图咳出一些涉及Jtable的代码。 我发现即使我添加了滚动条策略，也不会出现垂直滚动条。这段代码很破旧。（事先警告你）。但是，请您指出我需要在滚动条策略中添加的位置。我试过在很多地方添加它，它似乎似乎没有出现。
另一个问题是我如何制作一张空桌子。在每次单击进程按钮时，我想刷新表。你能指点我这个方向吗？
使用说明：只需在常规节点文本字段中输入一个数字，如5或10 然后单击过程按钮。
我的代码：
package ui;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.FlowLayout;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusEvent;
import java.awt.event.FocusListener;
import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTabbedPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.UIManager.LookAndFeelInfo;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.DefaultTableModel;
import utils.ThroughputUtility;
/**
* @author Nathan
*
*/
public class EntryPoint extends JPanel{
public boolean isProcesed =false;
static JFrame frame;
JTabbedPane jTabbedPane = new JTabbedPane();
private static final long serialVersionUID = -6490905886388876629L;
public String messageTobeSent = null;
public int regularNodeCount =0;
public static final String MESSAGE_TO_BE_SENT =" Please Enter the message to be sent. ";
protected static final String ONE = "1";
Map<String,Double> regNodeThroughputMap ;
static JTable tableOfValues;
Object columnNames[] = { "<html><b>Regular Node Name</b></htm>", "<html><b>Throughput Value Obtained</b></html>"};
Object rowData[][] = null;
public EntryPoint() {
jTabbedPane.setTabPlacement(JTabbedPane.NORTH);
Font font = new Font("Verdana", Font.BOLD, 12);
jTabbedPane.setFont(font);
//Server Side Panel.
JPanel serverPanel = getServerPanel();
jTabbedPane.addTab("Server", serverPanel);
//Client side Panel.
JPanel clientPanel = getClientPanel();
jTabbedPane.addTab("Client", clientPanel);
}
private JPanel getClientPanel() {
//Heading Label
JPanel clientPanel = new JPanel();
JLabel RegularNodeLabel = new JLabel("<html><u>Throughput Optimization For Mobile BackBone Networks</u></html>");
RegularNodeLabel.setFont(new Font("Algerian",Font.BOLD,20));
RegularNodeLabel.setForeground(new Color(176,23,31));
clientPanel.add(RegularNodeLabel);
return clientPanel;
}
/**Server Side Code
* @return
*/
private JPanel getServerPanel() {
//Heading Label
JPanel serverPanel = new JPanel(new FlowLayout());
final Box verticalBox1 = Box.createVerticalBox();
Box horozontalBox1 = Box.createHorizontalBox();
Box verticalBox2forsep = Box.createVerticalBox();
Box horozontalBox2 = Box.createHorizontalBox();
JPanel heading = new JPanel(new FlowLayout(FlowLayout.CENTER));
JLabel backBoneNodeLabel = new JLabel("<html><u>Throughput Optimization For Mobile BackBone Networks</u></html>");
backBoneNodeLabel.setFont(new Font("Algerian",Font.BOLD,20));
backBoneNodeLabel.setForeground(new Color(176,23,31));
backBoneNodeLabel.setAlignmentX(Component.CENTER_ALIGNMENT);
//Indication of BackBone Node
JPanel body = new JPanel(new FlowLayout(FlowLayout.LEFT));
JLabel backBoneNodeID = new JLabel("Fixed BackBone Node");
backBoneNodeID.setFont(new Font("Algerian",Font.BOLD,16));
backBoneNodeID.setForeground(new Color(176,23,31));
backBoneNodeID.setAlignmentX(Component.CENTER_ALIGNMENT);
//Seperator
JLabel seperator = new JLabel(" ");
seperator.setFont(new Font("Algerian",Font.BOLD,20));
seperator.setForeground(new Color(176,23,31));
verticalBox2forsep.add(seperator);
//Message label
JLabel messageLabel = new JLabel("Please enter the Message to be sent: ");
messageLabel.setFont(new Font("Algerian",Font.BOLD,16));
messageLabel.setForeground(new Color(176,23,31));
messageLabel.setAlignmentX(Component.LEFT_ALIGNMENT);
//Message Text
final JTextField messageText = new JTextField(MESSAGE_TO_BE_SENT,25);
messageText.addFocusListener(new FocusListener() {
@Override
public void focusLost(FocusEvent arg0) {
// TODO Auto-generated method stub
}
@Override
public void focusGained(FocusEvent arg0) {
if(messageText.getText().trim().equalsIgnoreCase(MESSAGE_TO_BE_SENT.trim())){
messageText.setText("");
}
}
});
horozontalBox1.add(messageLabel);
horozontalBox1.add(messageText);
//Regular node attached to backbone nodes.
JLabel regularNodelabel = new JLabel("Number of Regular nodes to be attached to the backbone node. ");
regularNodelabel.setFont(new Font("Algerian",Font.BOLD,16));
regularNodelabel.setForeground(new Color(176,23,31));
regularNodelabel.setAlignmentX(Component.LEFT_ALIGNMENT);
//Regular Node text
final JTextField regularNodeText = new JTextField(ONE,5);
regularNodeText.addFocusListener(new FocusListener() {
@Override
public void focusLost(FocusEvent e) {
// TODO Auto-generated method stub
}
@Override
public void focusGained(FocusEvent e) {
if(regularNodeText.getText().trim().equalsIgnoreCase(ONE.trim())){
regularNodeText.setText("");
tableOfValues = new JTable(0,0);
}
}
});
horozontalBox2.add(regularNodelabel);
horozontalBox2.add(regularNodeText);
//Button for Processing.
JButton processbutton = new JButton("Process");
processbutton.setFont(new Font("Algerian",Font.BOLD,16));
processbutton.setForeground(new Color(176,23,31));
processbutton.setAlignmentX(Component.CENTER_ALIGNMENT);
//Processing on clciking process button
processbutton.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
isProcesed=false;
Runnable runThread = new Runnable() {
@Override
public void run() {
while(!isProcesed){
try {
Thread.sleep(50);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
verticalBox1.add(tableOfValues);
isProcesed =false;
}
};
Thread processThread= new Thread(runThread);
processThread.start();
regularNodeCount = Integer.parseInt(regularNodeText.getText().trim());
regNodeThroughputMap = getThroughPutValues(regularNodeText.getText().trim());
System.out.println("Map obtained = "+regNodeThroughputMap);
tableOfValues = populateTable(regNodeThroughputMap);
isProcesed=true;
JScrollPane scrollPane = new JScrollPane(tableOfValues);
scrollPane.add(tableOfValues);
scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
verticalBox1.add(scrollPane,BorderLayout.CENTER);
// verticalBox1.add(scrollPane);
}
});
verticalBox1.add(backBoneNodeID);
verticalBox1.add(verticalBox2forsep);
verticalBox1.add(horozontalBox1);
verticalBox1.add(verticalBox2forsep);
verticalBox1.add(horozontalBox2);
verticalBox1.add(verticalBox2forsep);
verticalBox1.add(processbutton);
heading.add(backBoneNodeLabel);
//body.add(backBoneNodeID);
body.add(verticalBox1);
serverPanel.add(heading);
serverPanel.add(body);
return serverPanel;
}
protected JTable populateTable(Map<String,Double> regNodeThroughputMap) {
/*{ { "Row1-Column1", "Row1-Column2", "Row1-Column3" },
{ "Row2-Column1", "Row2-Column2", "Row2-Column3" } }*/
rowData = new Object[regularNodeCount+1][2];
Set<Map.Entry<String, Double>> set = regNodeThroughputMap.entrySet();
for (Map.Entry<String, Double> me : set) {
System.out.println("key ="+me.getKey());
System.out.println("Value ="+me.getValue());
}
String[] keys = new String[regularNodeCount+2];
String[] values = new String[regularNodeCount+2];
List<String> keyList = new LinkedList<String>();
List<String> valueList = new LinkedList<String>();
keyList.add("");
valueList.add("");
for(String key:regNodeThroughputMap.keySet()){
keyList.add(key);
}
for(double value:regNodeThroughputMap.values()){
System.out.println(value);
valueList.add(Double.toString(value));
}
keyList.toArray(keys);
valueList.toArray(values);
System.out.println(Arrays.asList(keys));
System.out.println(Arrays.asList(values));
rowData[0][0] =columnNames[0];
rowData[0][1] =columnNames[1];
for(int i=1;i<=regularNodeCount;i++){
for(int j=0;j<2;j++){
if(j==0)
rowData[i][j]=keys[i];
if(j==1)
rowData[i][j]=values[i];
}
}
return new JTable(rowData, columnNames);
//Printing the array
/* for (int i =0; i < regularNodeCount; i++) {
for (int j = 0; j < 2; j++) {
System.out.print(" " + rowData[i][j]);
}
System.out.println("");
}
*/
}
protected Map<String, Double> getThroughPutValues(String regularNodeInput) {
return ThroughputUtility.generateMapofNodeAndThroughput(regularNodeInput);
}
protected static void createAndShowGUI() {
//Create and set up the window.
frame = new JFrame("Throughput Optimization for Mobile BackBone Networks");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
EntryPoint splitPaneDemo = new EntryPoint();
frame.getContentPane().add(splitPaneDemo.jTabbedPane);
JScrollPane sp = new JScrollPane(tableOfValues);
sp.setBorder(BorderFactory.createEmptyBorder());
sp.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
sp.setHorizontalScrollBarPolicy(JScrollPane .HORIZONTAL_SCROLLBAR_AS_NEEDED);
frame.setResizable(false);
//Display the window.
frame.pack();
frame.setVisible(true);
frame.setSize(800,600);
}
public static void main(String[] args) {
try {
for (LookAndFeelInfo info : UIManager.getInstalledLookAndFeels()) {
if ("Nimbus".equals(info.getName())) {
UIManager.setLookAndFeel(info.getClassName());
break;
}
}
} catch (UnsupportedLookAndFeelException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (InstantiationException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
}
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
添加ThroughputUtility.java
package utils;
import java.util.LinkedHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
/**
* @author Nathan
*
*/
public class ThroughputUtility {
public static double MIN =5000;
public static double MAX =10000;
public static final double e =Math.E;
public static final double epsilon = 8.854187 *Math.pow(10,-12);
static int regularNodeCount;
static int counter ;
/**Generates the map of Node and ThroughPut values
* @param regularNodeInput
*/
public static Map<String,Double> generateMapofNodeAndThroughput(String regularNodeInput){
regularNodeCount = Integer.parseInt(regularNodeInput);
List<Double> randNodeDistances =getRandDistanceOfNodes(regularNodeCount);
Map<String,Double> nodeAndThroughputmap = getThroughputValuesForNodes(randNodeDistances);
System.out.println(nodeAndThroughputmap);
return nodeAndThroughputmap;
}
/** Obtains the throughput value based on the distances between
* the regular nodes and the backend Nodes.
* @param randNodeDistances
* @return
*/
private static Map<String, Double> getThroughputValuesForNodes(
List<Double> randNodeDistances) {
Map<String,Double> nodeAndThroughputmap = new LinkedHashMap<String, Double>();
for(double i : randNodeDistances){
double throughputValue = calculateThroughPut(i);
nodeAndThroughputmap.put("RegularNode :"+counter, throughputValue);
counter++;
}
return nodeAndThroughputmap;
}
private static double calculateThroughPut(double distanceij) {
double throughput = 1 /(e*regularNodeCount*distanceij*epsilon);
return throughput;
}
/**Generates the distance dij .
* @param regularNodeCount
* @return
*/
private static List<Double> getRandDistanceOfNodes(int regularNodeCount) {
List<Double> distnodeNumbers = new LinkedList<Double>();
for(int i=0;i<regularNodeCount;i++){
double randnodeNumber = MIN + (double)(Math.random() * ((MAX - MIN) + 1));
distnodeNumbers.add(randnodeNumber);
}
return distnodeNumbers;
}
public static void main(String[] args) {
ThroughputUtility.generateMapofNodeAndThroughput("5");
/*System.out.println(e);
System.out.println(epsilon);*/
}
}
答案 0 :(得分：3)
无法看到滚动条的主要问题是您将表格添加到多个容器中。
单击按钮时，你重新创建了很多摆动对象（为什么？），然后你启动一个线程将表添加到框中（为什么？如果你不知道你是什么，请小心摆动和多线程是做）。之后（或之前，取决于线程运行的时间长度），将表格添加到滚动窗格。
滚动窗格不包含您的表格，因为您只能使用它一次。
快速修复将是这样的： 创建所有GUI的东西一次，让它离开任何动作听众和东西。如果你启动应用程序，它应该只显示一个空表。不要将同一个对象添加到多个容器中！您可以使用
控制表格和滚动窗格的大小table.setPreferredSize(new Dimension(width, height));
如果单击按钮（位于动作侦听器中），则获取所有新数据并将其添加到表中。例如通过使用这样的东西。
tableOfValues.getModel().setValueAt(value, row, column);
或者如果必须创建新的表模型：
tableOfValues.setModel(new DefaultTableModel(rowData, columnNames));
通过查看代码，我现在可以告诉你了......
编辑： 在方法populateTable（...）中不要创建新表！如果必须，请使用上面的代码来设置新模型，或使用现有模型并修改其值。
答案 1 :(得分：2)
请参阅http://docs.oracle.com/javase/tutorial/uiswing/components/table.html
答案 2 :(得分：1)
我遇到了同样的问题，只需将JTable preferredsize设置为null，滚动条就会显示出来。
希望有所帮助