如何在Eclipse 3.8.1 RCP应用程序的“帮助”菜单下的“关于”条目中自定义文本和按钮

我正在尝试自定义Eclipse 3.8.1上的Help-> About菜单项。我尝试了两种3.x友好方法，因为Eclipse 4.0的工作方式有所不同。

--->我尝试扩展AboutAction本身（org.eclipse.ui.internal.dialogs.AboutDialog），这样我就可以在DialogArea Text中添加一行，并在单击License按钮时添加一个可滚动的Dialog Gui。但是所有方法在API中受到保护，我看到它说用户可以使用但不能覆盖（与Dialog类相同）

--->我尝试扩展默认的AbstractHandler，并在execute方法中创建一个Dialog对象，我基本上想逐一添加所有我需要的东西。唯一的问题是，我无法在execute方法中使用Dialog对象，因为在execute方法结束之前，它始终为null引用，因此如果没有nullPointerException困扰我，我将无法向其添加内容。

--->我也尝试添加<property>到plugin.xml本身。这似乎是4.x功能。“关于”菜单下的“描述”字段也无法在“关于”对话框文本区域中写入文本

    @SuppressWarnings("restriction")
    public class AboutActionStableHandler extends AbstractHandler {

public Object execute(ExecutionEvent event) throws ExecutionException 
{
    helpDialog = new AboutDialog(HandlerUtil.getActiveShellChecked(event));
    helpDialog.open();
    //helpDialog.getDialogArea(); 
    Shell aboutShell = helpDialog.getShell(); 
    aboutShell.setLayout(new GridLayout());
    Label version = new Label(aboutShell, SWT.NONE);
    version.setText(Platform.getProduct().getDefiningBundle().getVersion().toString());
    version.setLayoutData(GridDataBuilder.create().
    grabExcessHorizontalSpace(true).
    widthHint(500).
    heightHint(5).
    horizontalAlignment(SWT.FILL).build());
    return null;
}

因此，当我单击关于Gui时，我最终遇到了此运行时错误 java.lang.NullPointerException at com.magic.gui.commands.AboutActionStableHandler.execute(AboutActionStableHandler.java:28) at org.eclipse.ui.internal.handlers.HandlerProxy.execute(HandlerProxy.java:290) at org.eclipse.core.commands.Command.executeWithChecks(Command.java:499) at org.eclipse.core.commands.ParameterizedCommand.executeWithChecks(ParameterizedCommand.java:508) at org.eclipse.ui.internal.handlers.HandlerService.executeCommand(HandlerService.java:169) at org.eclipse.ui.internal.handlers.SlaveHandlerService.executeCommand(SlaveHandlerService.java:241) at org.eclipse.ui.menus.CommandContributionItem.handleWidgetSelection(CommandContributionItem.java:829) at org.eclipse.ui.menus.CommandContributionItem.access$19(CommandContributionItem.java:815) at org.eclipse.ui.menus.CommandContributionItem$5.handleEvent(CommandContributionItem.java:805) at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84) at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1053) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4169) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3758) at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2701) at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2665) at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2499) at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:679) at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332) at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:668) at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149) at com.magic.rcp.Application.start(Application.java:87) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584) at org.eclipse.equinox.launcher.Main.run(Main.java:1438) at org.eclipse.equinox.launcher.Main.main(Main.java:1414)