我正在使用适当的 GUI 和所有内容创建一个用于数据库操作的程序。我也在使用swing。无论如何，当我运行应用程序时，会打开以下窗口：
public class MusicShopManagementView extends FrameView {
public MusicShopManagementView(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);
}
}
});
// tracking table selection
masterTable.getSelectionModel().addListSelectionListener(
new ListSelectionListener() {
public void valueChanged(ListSelectionEvent e) {
firePropertyChange("recordSelected", !isRecordSelected(),
isRecordSelected());
}
});
// tracking changes to save
bindingGroup.addBindingListener(new AbstractBindingListener() {
@Override
public void targetChanged(Binding binding, PropertyStateEvent event) {
// save action observes saveNeeded property
setSaveNeeded(true);
}
});
// have a transaction started
entityManager.getTransaction().begin();
}
public boolean isSaveNeeded() {
return saveNeeded;
}
private void setSaveNeeded(boolean saveNeeded) {
if (saveNeeded != this.saveNeeded) {
this.saveNeeded = saveNeeded;
firePropertyChange("saveNeeded", !saveNeeded, saveNeeded);
}
}
public boolean isRecordSelected() {
return masterTable.getSelectedRow() != -1;
}
@Action
public void newRecord() {
musicshopmanagement.Intrument i = new musicshopmanagement.Intrument();
entityManager.persist(i);
list.add(i);
int row = list.size()-1;
masterTable.setRowSelectionInterval(row, row);
masterTable.scrollRectToVisible(masterTable.getCellRect(row, 0, true));
setSaveNeeded(true);
}
@Action(enabledProperty = "recordSelected")
public void deleteRecord() {
int[] selected = masterTable.getSelectedRows();
List<musicshopmanagement.Intrument> toRemove = new
ArrayList<musicshopmanagement.Intrument>(selected.length);
for (int idx=0; idx<selected.length; idx++) {
musicshopmanagement.Intrument i =
list.get(masterTable.convertRowIndexToModel(selected[idx]));
toRemove.add(i);
entityManager.remove(i);
}
list.removeAll(toRemove);
setSaveNeeded(true);
}
@Action(enabledProperty = "saveNeeded")
public Task save() {
return new SaveTask(getApplication());
}
private class SaveTask extends Task {
SaveTask(org.jdesktop.application.Application app) {
super(app);
}
@Override protected Void doInBackground() {
try {
entityManager.getTransaction().commit();
entityManager.getTransaction().begin();
} catch (RollbackException rex) {
rex.printStackTrace();
entityManager.getTransaction().begin();
List<musicshopmanagement.Intrument> merged = new
ArrayList<musicshopmanagement.Intrument>(list.size());
for (musicshopmanagement.Intrument i : list) {
merged.add(entityManager.merge(i));
}
list.clear();
list.addAll(merged);
}
return null;
}
@Override protected void finished() {
setSaveNeeded(false);
}
}
/**
* An example action method showing how to create asynchronous tasks
* (running on background) and how to show their progress. Note the
* artificial 'Thread.sleep' calls making the task long enough to see the
* progress visualization - remove the sleeps for real application.
*/
@Action
public Task refresh() {
return new RefreshTask(getApplication());
}
private class RefreshTask extends Task {
RefreshTask(org.jdesktop.application.Application app) {
super(app);
}
@SuppressWarnings("unchecked")
@Override protected Void doInBackground() {
try {
setProgress(0, 0, 4);
setMessage("Rolling back the current changes...");
setProgress(1, 0, 4);
entityManager.getTransaction().rollback();
setProgress(2, 0, 4);
setMessage("Starting a new transaction...");
entityManager.getTransaction().begin();
setProgress(3, 0, 4);
setMessage("Fetching new data...");
java.util.Collection data = query.getResultList();
for (Object entity : data) {
entityManager.refresh(entity);
}
setProgress(4, 0, 4);
list.clear();
list.addAll(data);
} catch(Exception ignore) { }
return null;
}
@Override protected void finished() {
setMessage("Done.");
setSaveNeeded(false);
}
}
@Action
public void showAboutBox() {
if (aboutBox == null) {
JFrame mainFrame = MusicShopManagementApp.getApplication().getMainFrame();
aboutBox = new MusicShopManagementAboutBox(mainFrame);
aboutBox.setLocationRelativeTo(mainFrame);
}
MusicShopManagementApp.getApplication().show(aboutBox);
}
@Action
public void showInventory() {
JFrame frame1 = new JFrame();
frame1.setContentPane(new InventoryForm());
frame1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame1.setVisible(true);
}
现在我想开另一个JPanel叫InventoryForm. 上面代码中的最后一个方法showInventory()应该是 open InventoryForm，但我得到一个错误：
线程“AWT-EventQueue-0”中的异常 java.lang.Error: java.lang.reflect.InvocationTargetException
在 org.jdesktop.application.ApplicationAction.actionFailed(ApplicationAction.java:859)
在 org.jdesktop.application.ApplicationAction.noProxyActionPerformed(ApplicationAction.java:665)
在 org.jdesktop.application.ApplicationAction.actionPerformed(ApplicationAction.java:698)
.....................
要么我的整个方法不正确，要么我（显然）在某个地方搞砸了。请帮忙！