Question

我们一直在研究一个非常奇怪的Widget is disposed异常。

我已经创建了一个基本示例。

import javax.annotation.PostConstruct;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.MouseAdapter;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Menu;

public class TestView {

    @PostConstruct
    public void postConstruct(final Composite parent) {

        final Composite composite = new Composite(parent, SWT.NONE);

        final Menu menu = new Menu(composite);

        composite.addMouseListener(new MouseAdapter() {

            @Override
            public void mouseDown(final MouseEvent e) {

                System.out.println(menu.isDisposed());

                menu.setVisible(true); // Widget is disposed exception
            }
        });
    }
}

已使用这些设置将其添加到零件堆栈中。

重新创建的步骤：

分离TestView
关闭TestView
重新打开TestView（使用partService.showPart("TestViewId", PartState.ACTIVATE)）
重新附加TestView
点击TestView

由于处理菜单而抛出Widget is disposed异常。

我向菜单项添加了Dispose侦听器。当零件重新连接到零件堆时将其放置。看来，当放置外壳时，它也在同时放置菜单。

这是处理后的堆栈跟踪。

java.lang.Exception: Stack trace
    at java.lang.Thread.dumpStack(Thread.java:1336)
    at TestView$1.widgetDisposed(TestView.java:25)
    at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:127)
    at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:89)
    at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4131)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1055)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1079)
    at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1060)
    at org.eclipse.swt.widgets.Widget.release(Widget.java:812)
    at org.eclipse.swt.widgets.Widget.dispose(Widget.java:429)
    at org.eclipse.swt.widgets.Decorations.releaseChildren(Decorations.java:736)
    at org.eclipse.swt.widgets.Shell.releaseChildren(Shell.java:1353)
    at org.eclipse.swt.widgets.Widget.release(Widget.java:815)
    at org.eclipse.swt.widgets.Widget.dispose(Widget.java:429)
    at org.eclipse.swt.widgets.Decorations.dispose(Decorations.java:408)
    at org.eclipse.swt.widgets.Shell.dispose(Shell.java:742)
    at org.eclipse.e4.ui.workbench.renderers.swt.SWTPartRenderer.disposeWidget(SWTPartRenderer.java:175)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.safeRemoveGui(PartRenderingEngine.java:958)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.access$1(PartRenderingEngine.java:886)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:881)
    at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.removeGui(PartRenderingEngine.java:865)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.subscribeTopicToBeRendered(PartRenderingEngine.java:186)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.eclipse.e4.core.internal.di.MethodRequestor.execute(MethodRequestor.java:58)
    at org.eclipse.e4.core.di.internal.extensions.EventObjectSupplier$DIEventHandler.handleEvent(EventObjectSupplier.java:91)
    at org.eclipse.equinox.internal.event.EventHandlerWrapper.handleEvent(EventHandlerWrapper.java:205)
    at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:203)
    at org.eclipse.equinox.internal.event.EventHandlerTracker.dispatchEvent(EventHandlerTracker.java:1)
    at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:233)
    at org.eclipse.osgi.framework.eventmgr.ListenerQueue.dispatchEventSynchronous(ListenerQueue.java:151)
    at org.eclipse.equinox.internal.event.EventAdminImpl.dispatchEvent(EventAdminImpl.java:132)
    at org.eclipse.equinox.internal.event.EventAdminImpl.sendEvent(EventAdminImpl.java:75)
    at org.eclipse.equinox.internal.event.EventComponent.sendEvent(EventComponent.java:44)
    at org.eclipse.e4.ui.services.internal.events.EventBroker.send(EventBroker.java:55)
    at org.eclipse.e4.ui.internal.workbench.UIEventPublisher.notifyChanged(UIEventPublisher.java:63)
    at org.eclipse.emf.common.notify.impl.BasicNotifierImpl.eNotify(BasicNotifierImpl.java:424)
    at org.eclipse.e4.ui.model.application.ui.impl.UIElementImpl.setToBeRendered(UIElementImpl.java:307)
    at org.eclipse.e4.ui.workbench.addons.cleanupaddon.CleanupAddon.lambda$1(CleanupAddon.java:335)
    at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:40)
    at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:185)
    at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3919)
    at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3550)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1173)
    at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
    at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1062)
    at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
    at org.eclipse.e4.ui.internal.workbench.swt.E4Application.start(E4Application.java:166)
    at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:137)
    at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:107)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
    at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:659)
    at org.eclipse.equinox.launcher.Main.basicRun(Main.java:595)
    at org.eclipse.equinox.launcher.Main.run(Main.java:1501)
    at org.eclipse.equinox.launcher.Main.main(Main.java:1474)

我尝试添加其他组件（例如按钮），但它们不会被丢弃。看来这仅发生在菜单上。

可能是什么原因造成的？

分离和重新连接部件时，小部件被处置为异常

0 个答案: