Question

我正在尝试开发一个eclipse插件。我知道这件事的基础知识。

在示例插件模板中，当我们在eclipse的测试实例中单击菜单项（或在这种情况下在下图中带有eclipse图标的按钮）时，执行 sampleHandler.java <的方法/ strong>已执行，并出现如下图所示的弹出窗口。

每当我在代码编辑器中按某个键（让我们说退格键）而不是单击任何菜单项（或按钮）时，我想调用'execute'方法。

SampleHandler.java

public class SampleHandler extends AbstractHandler { public SampleHandler() { } /** * the command has been executed, so extract extract the needed information * from the application context. */ public Object execute(ExecutionEvent event) throws ExecutionException { IWorkbenchWindow window = HandlerUtil.getActiveWorkbenchWindowChecked(event); MessageDialog.openInformation( window.getShell(), "Sdfsdfsadf", "Hello, Eclipse world"); return null; } }

我尝试了other posts中给出的建议，但我无法实现所需的功能。

根据我在上面的参考文章中的理解，我尝试了下面的代码 -

package eventlisten.handlers; import org.eclipse.core.commands.AbstractHandler; import org.eclipse.core.commands.ExecutionEvent; import org.eclipse.core.commands.ExecutionException; import org.eclipse.ui.IEditorInput; import org.eclipse.ui.IEditorPart; import org.eclipse.ui.IWorkbenchPage; import org.eclipse.ui.IWorkbenchWindow; import org.eclipse.ui.PlatformUI; import org.eclipse.ui.handlers.HandlerUtil; import org.eclipse.ui.texteditor.ITextEditor; import org.eclipse.jface.dialogs.MessageDialog; import org.eclipse.jface.text.DocumentEvent; import org.eclipse.jface.text.IDocument; import org.eclipse.jface.text.IDocumentListener; /** * Our sample handler extends AbstractHandler, an IHandler base class. * @see org.eclipse.core.commands.IHandler * @see org.eclipse.core.commands.AbstractHandler */ public class SampleHandler extends AbstractHandler { /** * The constructor. */ public SampleHandler() { } /** * the command has been executed, so extract extract the needed information * from the application context. */ public Object execute(ExecutionEvent event) throws ExecutionException { IWorkbenchWindow window = HandlerUtil.getActiveWorkbenchWindowChecked(event); MessageDialog.openInformation(window.getShell(),"EventListen","Trying event listen"); IWorkbenchPage page = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage(); IEditorPart editor = page.getActiveEditor(); IEditorInput input = editor.getEditorInput(); IDocument document=(((ITextEditor)editor).getDocumentProvider()).getDocument(IDocument.class); document.addDocumentListener(new IDocumentListener() //**this is line 45** { @Override public void documentAboutToBeChanged(DocumentEvent event) { // TODO Auto-generated method stub System.out.println("Hello"); } @Override public void documentChanged(DocumentEvent event) { // TODO Auto-generated method stub System.out.println("Hello second"); } }); return null; } }

但是在显示弹出窗口后，它会抛出异常 -

java.lang.NullPointerException at eventlisten.handlers.SampleHandler.execute(SampleHandler.java:45) 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:1276) at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:3562) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3186) 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 org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:124) 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(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) 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)

有人可以指导我完成整个过程吗？如果需要更多信息，请告诉我。

Answer 1

您的第一个问题似乎是当用户按下按钮时您只与文档交互。有更好的方法来设置它。
据我所知，您想要检测用户何时修改文档（可能通过键入），在任何地方键入任何键，或者修改代码的AST。您可能只会找到以下有用或相关的一个解决方案。

聆听文件更改

您尝试的解决方案最接近第一个解决方案，因此我将从那里开始。我做了这样的事情（在你链接的帖子中，事实证明）。首先让你的插件扩展org.eclipse.ui.startup扩展点，并定义一个类来覆盖IStartup

earlyStartup()看起来像是：

@Override
public void earlyStartup() {
    IWorkbench wb = PlatformUI.getWorkbench();
    wb.addWindowListener(generateWindowListener());
}

我们会听窗户打开，当他们这样做时，

private IWindowListener generateWindowListener() 
{
    return new IWindowListener() {
        @Override
        public void windowOpened(IWorkbenchWindow window) {
            IWorkbenchPage activePage = window.getActivePage(); 
            activePage.addPartListener(generateIPartListener2());
        }

        @Override
        public void windowDeactivated(IWorkbenchWindow window) {}

        @Override
        public void windowClosed(IWorkbenchWindow window) {}

        @Override
        public void windowActivated(IWorkbenchWindow window) {}
    };
}

此部分监听器是您应该获取EditorPart的地方，这意味着您可以添加文档监听器：

private IPartListener2 generateIPartListener2() 
{
    return new IPartListener2() {

        private void checkPart(IWorkbenchPartReference partRef) {
        IWorkbenchPart part = partRef.getPart(false);
            if (part instanceof IEditorPart)
            {
                IEditorPart editor = (IEditorPart) part;
                IEditorInput input = editor.getEditorInput();
                if (editor instanceof ITextEditor && input instanceof FileEditorInput)  //double check.  Error Editors can also bring up this call
                {
                    IDocument document=(((ITextEditor)editor).getDocumentProvider()).getDocument(input);
                    document.addDocumentListener(/* your listener from above*/);
                }
            }
        }

        @Override
        public void partOpened(IWorkbenchPartReference partRef) {
            checkPart(partRef);
        }

        @Override
        public void partInputChanged(IWorkbenchPartReference partRef) 
        {
            checkPart(partRef);
        }           

        @Override
        public void partVisible(IWorkbenchPartReference partRef){}

        @Override
        public void partHidden(IWorkbenchPartReference partRef) {}

        @Override
        public void partDeactivated(IWorkbenchPartReference partRef)  {}

        @Override
        public void partClosed(IWorkbenchPartReference partRef) {}

        @Override
        public void partBroughtToTop(IWorkbenchPartReference partRef) {}

        @Override
        public void partActivated(IWorkbenchPartReference partRef) {}
    };
}

只听取keypressess

这最终会更容易实现，但可能会非常嘈杂。我们正在查看Display和Listener，它们会直接进入SWT事件循环。

您希望再次执行earlyStartup（）扩展，并具有以下内容：

@Override
public void earlyStartup() {
    Display display = Display.getDefault();
    display.setFilter(SWT.KeyUp, new Listener() {
        @Override
        public void handleEvent(Event event) {
            //do stuff here.  Be careful, this may cause lag
        }
     });
}

听Java AST更改 最后一个具有原始keyup方法的简单性，但可能与我建议的第一个一样在语义上有用。我们将直接收听JavaCore。

再次，在earlyStartup方法（）

中

 JavaCore.addElementChangedListener(new IElementChangedListener() {

        @Override
        public void elementChanged(ElementChangedEvent event)
        {
            //do stuff with the event
        }
    });

结论：幸运的是，这三种方法中的一种对您有用。我有理由在我的Eclipse开发职业中使用每一个 - 每个都以自己的方式有用。

我希望这会有所帮助。

Eclipse插件开发：如何在Eclipse编辑器中监听事件

1 个答案: