Android - 不支持的服务 : audio

Question

我试图理解和解决我在 Eclipse 工作区日志中看到的错误，同时处理实现 IME 的 Android 应用程序。我是 Android 和 Eclipse 的新手。

错误是“com.utterkaos.keyboard.LatinKeyboardView 无法实例化”。

相关的堆栈跟踪是:

java.lang.UnsupportedOperationException: Unsupported Service: audio at com.android.layoutlib.bridge.android.BridgeContext.getSystemService(BridgeContext.java:434) at android.inputmethodservice.KeyboardView.(KeyboardView.java:376) at android.inputmethodservice.KeyboardView.(KeyboardView.java:279) at com.utterkaos.keyboard.LatinKeyboardView.(LatinKeyboardView.java:30) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.instantiateClass(ProjectCallback.java:402) at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.loadView(ProjectCallback.java:166) at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:207) at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:135) at android.view.LayoutInflater.inflate(LayoutInflater.java:466) at android.view.LayoutInflater.inflate(LayoutInflater.java:372) at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:321) at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:324) at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:325) at com.android.ide.eclipse.adt.internal.editors.layout.gle2.RenderService.createRenderSession(RenderService.java:372) at com.android.ide.eclipse.adt.internal.editors.layout.gle2.GraphicalEditorPart.renderWithBridge(GraphicalEditorPart.java:1361) at com.android.ide.eclipse.adt.internal.editors.layout.gle2.GraphicalEditorPart.recomputeLayout(GraphicalEditorPart.java:1115) at com.android.ide.eclipse.adt.internal.editors.layout.gle2.GraphicalEditorPart.activated(GraphicalEditorPart.java:941) at com.android.ide.eclipse.adt.internal.editors.layout.LayoutEditorDelegate.delegatePageChange(LayoutEditorDelegate.java:450) at com.android.ide.eclipse.adt.internal.editors.common.CommonXmlEditor.pageChange(CommonXmlEditor.java:358) at org.eclipse.ui.part.MultiPageEditorPart.setActivePage(MultiPageEditorPart.java:1067) at org.eclipse.ui.forms.editor.FormEditor.setActivePage(FormEditor.java:607) at com.android.ide.eclipse.adt.internal.editors.AndroidXmlEditor.selectDefaultPage(AndroidXmlEditor.java:380) at com.android.ide.eclipse.adt.internal.editors.AndroidXmlEditor.addPages(AndroidXmlEditor.java:285) at com.android.ide.eclipse.adt.internal.editors.common.CommonXmlEditor.addPages(CommonXmlEditor.java:283) at org.eclipse.ui.forms.editor.FormEditor.createPages(FormEditor.java:138) at org.eclipse.ui.part.MultiPageEditorPart.createPartControl(MultiPageEditorPart.java:348) at org.eclipse.ui.internal.EditorReference.createPartHelper(EditorReference.java:670) at org.eclipse.ui.internal.EditorReference.createPart(EditorReference.java:465) at org.eclipse.ui.internal.WorkbenchPartReference.getPart(WorkbenchPartReference.java:595) at org.eclipse.ui.internal.EditorReference.getEditor(EditorReference.java:289) at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditorBatched(WorkbenchPage.java:2945) at org.eclipse.ui.internal.WorkbenchPage.busyOpenEditor(WorkbenchPage.java:2850) at org.eclipse.ui.internal.WorkbenchPage.access$11(WorkbenchPage.java:2842) at org.eclipse.ui.internal.WorkbenchPage$10.run(WorkbenchPage.java:2793) at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:70) at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2789) at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2773) at org.eclipse.ui.internal.WorkbenchPage.openEditor(WorkbenchPage.java:2764) at org.eclipse.ui.ide.IDE.openEditor(IDE.java:651) at org.eclipse.ui.ide.IDE.openEditor(IDE.java:610) at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:355) at org.eclipse.jdt.internal.ui.javaeditor.EditorUtility.openInEditor(EditorUtility.java:164) at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:249) at org.eclipse.jdt.ui.actions.OpenAction.run(OpenAction.java:228) at org.eclipse.jdt.ui.actions.SelectionDispatchAction.dispatchRun(SelectionDispatchAction.java:275) at org.eclipse.jdt.ui.actions.SelectionDispatchAction.run(SelectionDispatchAction.java:251) at org.eclipse.jdt.internal.ui.packageview.PackageExplorerActionGroup.handleOpen(PackageExplorerActionGroup.java:376) at org.eclipse.jdt.internal.ui.packageview.PackageExplorerPart$4.open(PackageExplorerPart.java:538) at org.eclipse.ui.OpenAndLinkWithEditorHelper$InternalListener.open(OpenAndLinkWithEditorHelper.java:48) at org.eclipse.jface.viewers.StructuredViewer$2.run(StructuredViewer.java:866) at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42) at org.eclipse.ui.internal.JFaceUtil$1.run(JFaceUtil.java:49) at org.eclipse.jface.util.SafeRunnable.run(SafeRunnable.java:175) at org.eclipse.jface.viewers.StructuredViewer.fireOpen(StructuredViewer.java:864) at org.eclipse.jface.viewers.StructuredViewer.handleOpen(StructuredViewer.java:1152) at org.eclipse.jface.viewers.StructuredViewer$6.handleOpen(StructuredViewer.java:1256) at org.eclipse.jface.util.OpenStrategy.fireOpenEvent(OpenStrategy.java:275) at org.eclipse.jface.util.OpenStrategy.access$2(OpenStrategy.java:269) at org.eclipse.jface.util.OpenStrategy$1.handleEvent(OpenStrategy.java:309) 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:4165) at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3754) 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:123) 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:344) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:179) 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:622) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:577) at org.eclipse.equinox.launcher.Main.run(Main.java:1410) at org.eclipse.equinox.launcher.Main.main(Main.java:1386)

LatinKeyboardView.java 的相关部分是:

public class LatinKeyboardView extends KeyboardView {

    static final int KEYCODE_OPTIONS = -100;

    public LatinKeyboardView(Context context, AttributeSet attrs) {
        super(context, attrs);

}

第 30 行是“super(context, attrs);”

查看 KeyboardView.java，第 376 行:

mAudioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);

这里的“Context.AUDIO_SERVICE”似乎是字符串“audio”，它出现在错误堆栈跟踪中。

BridgeContext.java 的相关位是:

    public Object getSystemService(String service) {
414        if (LAYOUT_INFLATER_SERVICE.equals(service)) {
415            return mBridgeInflater;
416        }
417
418        if (TEXT_SERVICES_MANAGER_SERVICE.equals(service)) {
419            // we need to return a valid service to avoid NPE
420            return TextServicesManager.getInstance();
421        }
422
423        // AutoCompleteTextView and MultiAutoCompleteTextView want a window
424        // service. We don't have any but it's not worth an exception.
425        if (WINDOW_SERVICE.equals(service)) {
426            return null;
427        }
428
429        // needed by SearchView
430        if (INPUT_METHOD_SERVICE.equals(service)) {
431            return null;
432        }
433
434        throw new UnsupportedOperationException("Unsupported Service: " + service);
435    }

在这个例程中我发现特别令人费解的是，我看不出它如何处理“音频”服务，但 BridgeContext.java 和 KeyboardView.java 都是 Android 代码的一部分，而不是我写错的类。

任何帮助我理解为什么会发生此错误以及如何避免它的指针将不胜感激。

Answer 1

您使用的是 API 14 或更高版本吗？如果是这样，那就是问题所在。我想这是那个版本的错误。在 API 11 中它可以工作。

如果您尝试 API 11，则必须通过覆盖 getResources() 方法来做一些修改。查看this了解更多信息。在此之后它将起作用。

实际上我认为没有办法从 API 14(或者更高)上的 LatinKeyboardView 跳过这个，因为你甚至不能使用 isInEditMode() 因为你肯定必须用 super 调用 View 的构造函数。并且该构造函数将尝试获取音频系统服务，该服务只是失败了，因为我猜您尝试在 Eclipse 图形编辑器中运行它(实际上，当我尝试将自定义 View 放入图形布局编辑器中的布局时出现此错误)

我认为破解此问题的唯一方法是在没有 getSystemService 的情况下实现您自己的 KeyboardView。如果 isInEditMode == true，也许不应该调用该方法。