哪位熟悉netbeans？为什么在netbeans下，panel上的组件老是自动刷新？

Question

是不是netbeans的初始化init()代码中有什么初始化，每次事件相应后，又回到老状态，老位置？

Answer 1

init?是JApplet程序？楼主应该把代码贴出来

Answer 2

/*
 * Test1View.java
 */package test1;import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import org.jdesktop.application.Action;
import org.jdesktop.application.ResourceMap;
import org.jdesktop.application.SingleFrameApplication;
import org.jdesktop.application.FrameView;
import org.jdesktop.application.TaskMonitor;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Vector;
import javax.swing.Timer;
import javax.swing.Icon;
import javax.swing.JDialog;
import javax.swing.JFrame;/**
 * The application's main frame.
 */
public class Test1View extends FrameView {
    private int click1 = 0;
    private int x1;
    private int y1;
    private Point jd1p = new Point();
    private Point jl1p = new Point();
    private Vector<Point> endPoints1 = new Vector<Point>();
    private Vector<Point> endPoints2 = new Vector<Point>();
    private int endx;
    private int endy;    public Test1View(SingleFrameApplication app) {
       super(app);        initComponents();
        jLabel1.setVisible(false);
        jLabel2.setVisible(false);        // status bar initialization - message timeout, idle icon and busy animation, etc
        ResourceMap resourceMap = getResourceMap();
        int messageTimeout = resourceMap.getInteger("StatusBar.messageTimeout");
        messageTimer = new Timer(messageTimeout, new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                statusMessageLabel.setText("");
            }
        });
        messageTimer.setRepeats(false);
        int busyAnimationRate = resourceMap.getInteger("StatusBar.busyAnimationRate");
        for (int i = 0; i < busyIcons.length; i++) {
            busyIcons[i] = resourceMap.getIcon("StatusBar.busyIcons[" + i + "]");
        }
        busyIconTimer = new Timer(busyAnimationRate, new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                busyIconIndex = (busyIconIndex + 1) % busyIcons.length;
                statusAnimationLabel.setIcon(busyIcons[busyIconIndex]);
            }
        });
        idleIcon = resourceMap.getIcon("StatusBar.idleIcon");
        statusAnimationLabel.setIcon(idleIcon);
        progressBar.setVisible(false);        // connecting action tasks to status bar via TaskMonitor
        TaskMonitor taskMonitor = new TaskMonitor(getApplication().getContext());
        taskMonitor.addPropertyChangeListener(new java.beans.PropertyChangeListener() {
            public void propertyChange(java.beans.PropertyChangeEvent evt) {
                String propertyName = evt.getPropertyName();
                if ("started".equals(propertyName)) {
                    if (!busyIconTimer.isRunning()) {
                        statusAnimationLabel.setIcon(busyIcons[0]);
                        busyIconIndex = 0;
                        busyIconTimer.start();
                    }
                    progressBar.setVisible(true);
                    progressBar.setIndeterminate(true);
                } else if ("done".equals(propertyName)) {
                    busyIconTimer.stop();
                    statusAnimationLabel.setIcon(idleIcon);
                    progressBar.setVisible(false);
                    progressBar.setValue(0);
                } else if ("message".equals(propertyName)) {
                    String text = (String)(evt.getNewValue());
                    statusMessageLabel.setText((text == null) ? "" : text);
                    messageTimer.restart();
                } else if ("progress".equals(propertyName)) {
                    int value = (Integer)(evt.getNewValue());
                    progressBar.setVisible(true);
                    progressBar.setIndeterminate(false);
                    progressBar.setValue(value);
                }
            }
        });
    }

Answer 3

   @Action
    public void showAboutBox() {
        if (aboutBox == null) {
            JFrame mainFrame = Test1App.getApplication().getMainFrame();
            aboutBox = new Test1AboutBox(mainFrame);
            aboutBox.setLocationRelativeTo(mainFrame);
        }
        Test1App.getApplication().show(aboutBox);
    }    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    @SuppressWarnings("unchecked")
    // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
    private void initComponents() {        mainPanel = new javax.swing.JPanel();
        jLabel1 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();
        jButton1 = new javax.swing.JButton();
        menuBar = new javax.swing.JMenuBar();
        javax.swing.JMenu fileMenu = new javax.swing.JMenu();
        jMenuItem1 = new javax.swing.JMenuItem();
        javax.swing.JMenuItem exitMenuItem = new javax.swing.JMenuItem();
        javax.swing.JMenu helpMenu = new javax.swing.JMenu();
        javax.swing.JMenuItem aboutMenuItem = new javax.swing.JMenuItem();
        statusPanel = new javax.swing.JPanel();
        javax.swing.JSeparator statusPanelSeparator = new javax.swing.JSeparator();
        statusMessageLabel = new javax.swing.JLabel();
        statusAnimationLabel = new javax.swing.JLabel();
        progressBar = new javax.swing.JProgressBar();        mainPanel.setName("mainPanel"); // NOI18N        org.jdesktop.application.ResourceMap resourceMap = org.jdesktop.application.Application.getInstance(test1.Test1App.class).getContext().getResourceMap(Test1View.class);
        jLabel1.setBackground(resourceMap.getColor("jLabel1.background")); // NOI18N
        jLabel1.setText(resourceMap.getString("jLabel1.text")); // NOI18N
        jLabel1.setName("jLabel1"); // NOI18N
        jLabel1.addMouseListener(new java.awt.event.MouseAdapter() {
            public void mousePressed(java.awt.event.MouseEvent evt) {
                jLabel1MousePressed(evt);
            }
        });
        jLabel1.addMouseMotionListener(new java.awt.event.MouseMotionAdapter() {
            public void mouseDragged(java.awt.event.MouseEvent evt) {
                jLabel1MouseDragged(evt);
            }
        });        jLabel2.setText(resourceMap.getString("jLabel2.text")); // NOI18N
        jLabel2.setName("jLabel2"); // NOI18N        jButton1.setText(resourceMap.getString("jButton1.text")); // NOI18N
        jButton1.setName("jButton1"); // NOI18N        javax.swing.GroupLayout mainPanelLayout = new javax.swing.GroupLayout(mainPanel);
        mainPanel.setLayout(mainPanelLayout);
        mainPanelLayout.setHorizontalGroup(
            mainPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(mainPanelLayout.createSequentialGroup()
                .addGap(107, 107, 107)
                .addComponent(jButton1)
                .addContainerGap(298, Short.MAX_VALUE))
            .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, mainPanelLayout.createSequentialGroup()
                .addContainerGap(360, Short.MAX_VALUE)
                .addGroup(mainPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                    .addComponent(jLabel2)
                    .addComponent(jLabel1))
                .addGap(84, 84, 84))
        );
        mainPanelLayout.setVerticalGroup(
            mainPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(mainPanelLayout.createSequentialGroup()
                .addGap(75, 75, 75)
                .addComponent(jLabel1)
                .addGap(83, 83, 83)
                .addComponent(jLabel2)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 82, Short.MAX_VALUE)
                .addComponent(jButton1)
                .addGap(57, 57, 57))
        );        menuBar.setName("menuBar"); // NOI18N        fileMenu.setText(resourceMap.getString("fileMenu.text")); // NOI18N
        fileMenu.setName("fileMenu"); // NOI18N        jMenuItem1.setText(resourceMap.getString("jMenuItem1.text")); // NOI18N
        jMenuItem1.setName("jMenuItem1"); // NOI18N
        jMenuItem1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                jMenuItem1ActionPerformed(evt);
            }
        });
        fileMenu.add(jMenuItem1);        javax.swing.ActionMap actionMap = org.jdesktop.application.Application.getInstance(test1.Test1App.class).getContext().getActionMap(Test1View.class, this);
        exitMenuItem.setAction(actionMap.get("quit")); // NOI18N
        exitMenuItem.setName("exitMenuItem"); // NOI18N
        fileMenu.add(exitMenuItem);        menuBar.add(fileMenu);        helpMenu.setText(resourceMap.getString("helpMenu.text")); // NOI18N
        helpMenu.setName("helpMenu"); // NOI18N        aboutMenuItem.setAction(actionMap.get("showAboutBox")); // NOI18N
        aboutMenuItem.setName("aboutMenuItem"); // NOI18N
        helpMenu.add(aboutMenuItem);        menuBar.add(helpMenu);        statusPanel.setName("statusPanel"); // NOI18N        statusPanelSeparator.setName("statusPanelSeparator"); // NOI18N        statusMessageLabel.setName("statusMessageLabel"); // NOI18N        statusAnimationLabel.setHorizontalAlignment(javax.swing.SwingConstants.LEFT);
        statusAnimationLabel.setName("statusAnimationLabel"); // NOI18N        progressBar.setName("progressBar"); // NOI18N        javax.swing.GroupLayout statusPanelLayout = new javax.swing.GroupLayout(statusPanel);
        statusPanel.setLayout(statusPanelLayout);
        statusPanelLayout.setHorizontalGroup(
            statusPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addComponent(statusPanelSeparator, javax.swing.GroupLayout.DEFAULT_SIZE, 486, Short.MAX_VALUE)
            .addGroup(statusPanelLayout.createSequentialGroup()
                .addContainerGap()
                .addComponent(statusMessageLabel)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 316, Short.MAX_VALUE)
                .addComponent(progressBar, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                .addComponent(statusAnimationLabel)
                .addContainerGap())
        );
        statusPanelLayout.setVerticalGroup(
            statusPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
            .addGroup(statusPanelLayout.createSequentialGroup()
                .addComponent(statusPanelSeparator, javax.swing.GroupLayout.PREFERRED_SIZE, 2, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addGroup(statusPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.BASELINE)
                    .addComponent(statusMessageLabel)
                    .addComponent(statusAnimationLabel)
                    .addComponent(progressBar, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE))
                .addGap(3, 3, 3))
        );        setComponent(mainPanel);
        setMenuBar(menuBar);
        setStatusBar(statusPanel);
    }// </editor-fold>           

Answer 4

    private void jMenuItem1ActionPerformed(java.awt.event.ActionEvent evt) {                                           
        // TODO add your handling code here:
       if(click1 == 0){
             jLabel1.setVisible(true);
             System.out.println("jLable 1 ");
             
        }else{     
                  System.out.println("jLable 1' ");
                  jLabel1.setLocation(50,50);
                  jLabel2.setVisible(true);
                  System.out.println("jLable 2 ");
             }
                                            
        click1++;      
    }                                              private void jLabel1MouseDragged(java.awt.event.MouseEvent evt) {                                     
        // TODO add your handling code here:
         endx = jLabel1.getX() + evt.getX() - x1;
         endy = jLabel1.getY() + evt.getY() - y1;
         jd1p.x = endx;
         jd1p.y = endy;
         jLabel1.setLocation(jd1p);        
         jLabelMouseDragged(jl1p,jd1p);       
    }                                        private void jLabel1MousePressed(java.awt.event.MouseEvent evt) {                                     
        // TODO add your handling code here:
          x1 = evt.getX();
          y1 = evt.getY();  
    }                                        // Variables declaration - do not modify                     
    private javax.swing.JButton jButton1;
    private javax.swing.JLabel jLabel1;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JMenuItem jMenuItem1;
    private javax.swing.JPanel mainPanel;
    private javax.swing.JMenuBar menuBar;
    private javax.swing.JProgressBar progressBar;
    private javax.swing.JLabel statusAnimationLabel;
    private javax.swing.JLabel statusMessageLabel;
    private javax.swing.JPanel statusPanel;
    // End of variables declaration                       private final Timer messageTimer;
    private final Timer busyIconTimer;
    private final Icon idleIcon;
    private final Icon[] busyIcons = new Icon[15];
    private int busyIconIndex = 0;    private JDialog aboutBox;    public void jLabelMouseDragged(Point jlp,Point jdp) {                                     
        // TODO add your handling code here:  
         if(endPoints2.contains(jlp) == true && endPoints1.get(endPoints2.indexOf(jlp)) != null){                
                  try{
                      int j = endPoints2.indexOf(jlp);
                      Graphics g=mainPanel.getGraphics();
                      Graphics2D g2 = (Graphics2D)g;
                      endPoints2.remove(j);
                      endPoints2.add(j,jdp);
                      g2.setColor(Color.red);
                      g2.setStroke(new BasicStroke(3));
                      paint(g2);  
                  }catch(Exception e){
                       System.out.println("throw exception");
                  }               
         }else{
                  try{
                      int j = endPoints2.indexOf(jdp);
                      Graphics g=mainPanel.getGraphics();
                      Graphics2D g2 = (Graphics2D)g;
                      endPoints2.remove(j);
                      endPoints2.add(j,jdp);
                      g2.setColor(Color.red);
                      g2.setStroke(new BasicStroke(3));
                      paint(g2);  
                  }catch(Exception e){
                      System.out.println("throw exception");
                  }                                 
         }
    }    
     public void paint (Graphics g) {
                    Graphics2D g2 = (Graphics2D)g;
                    //mainPanel.update(g2);
                    if(endPoints1.size() <= endPoints2.size()){
                        for (int i=0; i<endPoints1.size(); i++)
                        g.drawLine(endPoints1.get(i).x, endPoints1.get(i).y, endPoints2.get(i).x, endPoints2.get(i).y);
                    }else{
                          for (int i=0; i<endPoints2.size(); i++)
                          g.drawLine(endPoints1.get(i).x, endPoints1.get(i).y, endPoints2.get(i).x, endPoints2.get(i).y);
                    }
                      
            }
    
      
}