伴随库中的MiniController按钮工作正常并且完全符合它的需要，但是在我们的项目中，在我们实现MiniController Button的每个布局中，预览窗格（在XML模式下）总是存在渲染错误。
错误是：
java.lang.IllegalStateException: No VideoCastManager instance was found, did you forget to initialize it?
at com.google.android.libraries.cast.companionlibrary.cast.VideoCastManager.getInstance(VideoCastManager.java:259)
at com.google.android.libraries.cast.companionlibrary.widgets.MiniController.<init>(MiniController.java:111)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:465)
at org.jetbrains.android.uipreview.ViewLoader.loadClass(ViewLoader.java:172)
at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:105)
at com.android.tools.idea.rendering.LayoutlibCallbackImpl.loadView(LayoutlibCallbackImpl.java:176)
at android.view.BridgeInflater.loadCustomView(BridgeInflater.java:247)
at android.view.BridgeInflater.createViewFromTag(BridgeInflater.java:171)
at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:704)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:835)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:70)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:811)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:838)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:70)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:811)
at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:798)
at android.view.LayoutInflater.inflate(LayoutInflater.java:515)
at android.view.LayoutInflater.inflate(LayoutInflater.java:394)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:229)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:426)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:350)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:520)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:508)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:967)
at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:508)
at com.android.tools.idea.rendering.RenderTask.access$600(RenderTask.java:75)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:620)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:617)
at com.android.tools.idea.rendering.RenderService.runRenderAction(RenderService.java:371)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:617)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:639)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.doRender(AndroidLayoutPreviewToolWindowManager.java:654)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.access$1700(AndroidLayoutPreviewToolWindowManager.java:82)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$7$1.run(AndroidLayoutPreviewToolWindowManager.java:596)
at com.intellij.openapi.progress.impl.CoreProgressManager$2.run(CoreProgressManager.java:142)
at com.intellij.openapi.progress.impl.CoreProgressManager.registerIndicatorAndRun(CoreProgressManager.java:446)
at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:392)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:54)
at com.intellij.openapi.progress.impl.CoreProgressManager.runProcess(CoreProgressManager.java:127)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$7.run(AndroidLayoutPreviewToolWindowManager.java:591)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:337)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:327)
at com.intellij.util.ui.update.MergingUpdateQueue$3.run(MergingUpdateQueue.java:271)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:286)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:244)
at com.intellij.util.ui.update.MergingUpdateQueue.run(MergingUpdateQueue.java:234)
at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:238)
at com.intellij.util.Alarm$Request$1.run(Alarm.java:352)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
问题是MiniController的构造函数试图获取VideoCastManager实例，但是当应用程序未运行时，该实例不可用。
public MiniController(Context context, AttributeSet attrs) {
super(context, attrs);
LayoutInflater inflater = LayoutInflater.from(context);
inflater.inflate(R.layout.mini_controller, this);
TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.MiniController);
mAutoSetup = a.getBoolean(R.styleable.MiniController_auto_setup, false);
a.recycle();
mPauseDrawable = getResources().getDrawable(R.drawable.ic_mini_controller_pause);
mPlayDrawable = getResources().getDrawable(R.drawable.ic_mini_controller_play);
mStopDrawable = getResources().getDrawable(R.drawable.ic_mini_controller_stop);
mHandler = new Handler();
mCastManager = VideoCastManager.getInstance();
loadViews();
setUpCallbacks();
}
我已经尝试从MiniController类创建一个子节点，但由于错误发生在构造函数中，我被强制调用super作为第一行构造函数调用。
有人知道摆脱这个错误的方法吗？ （只是为了确定：我知道我可以分叉CastCompanionLibrary并使用View.isInEditMode（），但我真的希望有更好的方法来解决这个问题。）
提前致谢：）