在我更新了gradle和Android Studio以及构建工具之后，当我转到任何xml文件时，我在Android Studio中遇到了这个奇怪的问题：
Rendering Problems The following classes could not be instantiated:
- com.android.internal.widget.ActionBarView
java.lang.NullPointerException
at android.content.res.BridgeResources.getLayout(BridgeResources.java:255)
at android.view.LayoutInflater.inflate(LayoutInflater.java:408)
at com.android.internal.widget.ActionBarView.<init>(ActionBarView.java:212)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:375)
at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:100)
at com.android.tools.idea.rendering.LayoutlibCallback.loadView(LayoutlibCallback.java:172)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:207)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:132)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:802)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:64)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:778)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:805)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:64)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:778)
at android.view.LayoutInflater.inflate(LayoutInflater.java:500)
at android.view.LayoutInflater.inflate(LayoutInflater.java:410)
at com.android.layoutlib.bridge.bars.ActionBarLayout.<init>(ActionBarLayout.java:96)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.createActionBar(RenderSessionImpl.java:1620)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:352)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:329)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:332)
at com.android.tools.idea.rendering.RenderService$3.compute(RenderService.java:575)
at com.android.tools.idea.rendering.RenderService$3.compute(RenderService.java:564)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:932)
at com.android.tools.idea.rendering.RenderService.createRenderSession(RenderService.java:564)
at com.android.tools.idea.rendering.RenderService.render(RenderService.java:691)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.doRender(AndroidLayoutPreviewToolWindowManager.java:586)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.access$1900(AndroidLayoutPreviewToolWindowManager.java:80)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$6$1.run(AndroidLayoutPreviewToolWindowManager.java:528)
at com.intellij.openapi.progress.impl.ProgressManagerImpl$2.run(ProgressManagerImpl.java:178)
at com.intellij.openapi.progress.ProgressManager.executeProcessUnderProgress(ProgressManager.java:209)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:212)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.runProcess(ProgressManagerImpl.java:171)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$6.run(AndroidLayoutPreviewToolWindowManager.java:523)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:320)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:310)
at com.intellij.util.ui.update.MergingUpdateQueue$2.run(MergingUpdateQueue.java:254)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:269)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:227)
at com.intellij.util.ui.update.MergingUpdateQueue.run(MergingUpdateQueue.java:217)
at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:238)
at com.intellij.util.Alarm$Request$1.run(Alarm.java:327)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:439)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
at java.lang.Thread.run(Thread.java:695)
应用程序在手机上运行正常，布局正确。只是我无法在Android Studio中预览它。
我尝试不使用上面的支持库v7和目标apk 11，但它不会删除错误。
答案 0 :(得分：0)
最后我自己找到了一个解决方案。
首先，我使用Android Studio创建了一个新项目，然后通过外部操作（复制和粘贴）添加了所有源文件和资源文件。
然后我将gradle.build改为：
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile files('libs/YouTubeAndroidPlayerApi.jar')
// compile 'com.android.support:appcompat-v7:19.0.+'
compile 'com.google.android.gms:play-services:5.0.+'
}
这部分解决了问题，然而，预览仍然显示布局的缺少样式，因此我转到布局的设计选项卡并手动选择合适的一个（例如Holo.Light）。现在一切正常。
答案 1 :(得分：0)
在预览屏幕中，只需将主题更改为Holo.Light，它对我有用。无需更改grandle.build文件。