Android测试：等待视图层次结构的根目录具有窗口焦点

在 Android Ui测试中,我想在对话框中单击一个微调器项,但是会弹出以下错误：

va.lang.RuntimeException: Waited for the root of the view hierarchy to have window focus and not be requesTing layout for over 10 seconds. If you specified a non default root matcher,it may be picking a root that never takes focus. Otherwise,something is serIoUsly wrong. SELEcted Root:
Root{application-window-token=android.view.ViewRootImpl$W@2dac97c7,window-token=android.view.ViewRootImpl$W@2dac97c7,has-window-focus=false,layout-params-type=1,layout-params-String=Wm.LayoutParams{(0,0)(fillxfill) sim=#10 ty=1 fl=#81810100 pfl=0x8 wanim=0x1030461 surfaceInsets=Rect(0,0 - 0,0) mwfl=0x0},decor-view-String=MultiPhoneDecorView{id=-1,visibility=VISIBLE,width=1600,height=2560,has-focus=true,has-focusable=true,is-clickable=false,is-enabled=true,is-focused=false,is-focusable=false,is-layout-requested=false,is-SELEcted=false,root-is-layout-requested=false,has-input-connection=false,x=0.0,y=0.0,child-count=1}}
. All Roots:
Root{application-window-token=android.view.ViewRootImpl$W@3c913e1,window-token=android.view.ViewRootImpl$W@21b23506,has-window-focus=true,layout-params-type=1002,layout-params-String=Wm.LayoutParams{(310,600)(722x480) gr=#10000033 sim=#1 ty=1002 fl=#1860200 fmt=-3 wanim=0x10302db surfaceInsets=Rect(0,decor-view-String=PopupViewContainer{id=-1,width=722,height=480,child-count=1}}
Root{application-window-token=android.view.ViewRootImpl$W@3c913e1,window-token=android.view.ViewRootImpl$W@3c913e1,layout-params-type=2,0)(wrapxwrap) gr=#11 sim=#20 ty=2 fl=#1800002 pfl=0x8 fmt=-3 wanim=0x1030462 surfaceInsets=Rect(0,0) mwfl=0x10},decor-view-String=DecorView{id=-1,width=1136,height=1058,child-count=1}}
Root{application-window-token=android.view.ViewRootImpl$W@2dac97c7,child-count=1}}
at android.support.test.espresso.base.RootViewPicker.get(RootViewPicker.java:99)
at android.support.test.espresso.ViewInteractionModule.provideRootView(ViewInteractionModule.java:69)
at android.support.test.espresso.ViewInteractionModule_ProvideRootViewFactory.get(ViewInteractionModule_ProvideRootViewFactory.java:23)
at android.support.test.espresso.ViewInteractionModule_ProvideRootViewFactory.get(ViewInteractionModule_ProvideRootViewFactory.java:9)
at android.support.test.espresso.base.ViewFinderImpl.getView(ViewFinderImpl.java:68)
at android.support.test.espresso.ViewInteraction$1.run(ViewInteraction.java:120)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:422)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.Handler.handleCallBACk(Handler.java:739)
at android.os.Handler.dispatchmessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6117)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)

我试过了

onData(allOf(is(instanceOf(String.class)),containsString("A4"))).inRoot(isPlatformPopup()).perform(click());

和

onView(withText(containsString("A4"))).inRoot(isFocusable()).check(matches(isDisplayed()));

和

onView(withText(containsString("A4"))).inRoot(withDecorView(not(getActivity().getWindow().getDecorView()))).check(matches(isDisplayed()));

但它们都不起作用……
有人能告诉我如何获得ralavant root吗？

onView(withText(containsString("A4"))).inRoot(isPlatformPopup()).check(matches(isDisplayed()));