Java/Swing+NetBeans 6.1. Keyboard event is not working
I need to move a Label-control on the form.
I have created a "Java Desktop Application" in NetBeans 6.1.
I have added the following code:
But the label is not moving.
Why?
/*
* DesktopApplication1View.java
*/
package desktopapplication1;
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.awt.event.KeyEvent;
import javax.swing.Timer;
import javax.swing.Icon;
import javax.swing.JDialog;
import javax.swing.JFrame;
/**
* The application's main frame.
*/
public class DesktopApplication1View extends FrameView {
public DesktopApplication1View(SingleFrameApplication app)
{
super(app);
initComponents();
// 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);
}
}
});
jLabel1.isOptimizedDrawingEnabled();
jLabel1.requestFocusInWindow();
}
@Action
public void showAboutBox() {
if (aboutBox == null) {
JFrame mainFrame = DesktopApplication1.getApplication().getMainFrame();
aboutBox = new DesktopApplication1AboutBox(mainFrame);
aboutBox.setLocationRelativeTo(mainFrame);
}
DesktopApplication1.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();
menuBar = new javax.swing.JMenuBar();
javax.swing.JMenu fileMenu = new javax.swing.JMenu();
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(desktopapplication1.DesktopApplication1.class).getContext().getResourceMap(DesktopApplication1View.class);
jLabel1.setText(resourceMap.getString("jLabel1.text")); // NOI18N
jLabel1.setName("jLabel1"); // NOI18N
jLabel1.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(java.awt.event.KeyEvent evt) {
jLabel1KeyPressed(evt);
}
});
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(151, 151, 151)
.addComponent(jLabel1)
.addContainerGap(215, Short.MAX_VALUE))
);
mainPanelLayout.setVerticalGroup(
mainPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
.addGroup(mainPanelLayout.createSequentialGroup()
.addGap(83, 83, 83)
.addComponent(jLabel1)
.addContainerGap(155, Short.MAX_VALUE))
);
menuBar.setName("menuBar"); // NOI18N
fileMenu.setText(resourceMap.getString("fileMenu.text")); // NOI18N
fileMenu.setName("fileMenu"); // NOI18N
javax.swing.ActionMap actionMap = org.jdesktop.application.Application.getInstance(desktopapplication1.DesktopApplication1.class).getContext().getActionMap(DesktopApplication1View.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, 400, Short.MAX_VALUE)
.addGroup(statusPanelLayout.createSequentialGroup()
.addContainerGap()
.addComponent(statusMessageLabel)
.addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 226, 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>
private void j开发者_Python百科Label1KeyPressed(java.awt.event.KeyEvent evt) {
// TODO add your handling code here:
int keyCode = evt.getKeyCode();
int xPos = jLabel1.getX();
int yPos = jLabel1.getY();
switch(keyCode)
{
case KeyEvent.VK_UP:
jLabel1.setLocation(xPos, --yPos);
break;
case KeyEvent.VK_DOWN:
jLabel1.setLocation(xPos, ++yPos);
break;
case KeyEvent.VK_LEFT:
jLabel1.setLocation(--xPos, yPos);
break;
case KeyEvent.VK_RIGHT:
jLabel1.setLocation(++xPos, yPos);
break;
}
}
// Variables declaration - do not modify
private javax.swing.JLabel jLabel1;
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;
}
Take a look at the Swing tutorial.
1) Only components that have focus can receive KeyEvents. By default a JLabel is not focusable so it will never receive a KeyEvent. A better way to do this is to use Key Bindings. See the section from the Swing tutorial on Key Bindings.
2) If you fix 1, then the label might move, but it won't stay in its new position if the frame is resized, because the layout manager will be invoked and will reposition the label based on its rules.
Read the section from the Swing tutorial on Using Layout Managers. If you really need the label to be in a random position then you will need to use Absolute Positioning which is also discussed in the tutorial.
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