将ViewPager置于AppBayLayout中，我在FrameLayout.LayoutParams和CoordinatorLayout.LayoutParams之间得到一个强制转换异常。如果我使用以下xml中的ImageView切换ViewPager，它可以很好地工作。关于什么可行的任何建议？我想要嵌入一个图像滑块，当webview向上滚动时，这些图像会消失。我已经尝试将ViewPager放在其他布局中，例如LinearLayout和FrameLayout，但同样的问题。
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/fragmentListing2"
android:fitsSystemWindows="true">
<android.support.v4.widget.NestedScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/rvToDoList"
app:layout_behavior="@string/appbar_scrolling_view_behavior">
<WebView
android:layout_width="match_parent"
android:layout_height="fill_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
android:id="@+id/lstWebviewDescription">
</WebView>
</android.support.v4.widget.NestedScrollView>
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/lstAppBarLayout"
android:fitsSystemWindows="true"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.CollapsingToolbarLayout
android:id="@+id/collapsing_toolbar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
app:contentScrim="?attr/colorPrimary"
app:expandedTitleMarginEnd="64dp"
app:expandedTitleMarginStart="48dp"
app:layout_scrollFlags="scroll|exitUntilCollapsed">
<android.support.v4.view.ViewPager
android:layout_width="match_parent"
android:layout_height="200dp"
android:id="@+id/lstImageAds"
app:layout_collapseMode="parallax">
</android.support.v4.view.ViewPager>
<include
android:id="@+id/lstToolbar"
layout="@layout/toolbar"
android:layout_height="?attr/actionBarSize"
app:layout_collapseMode="pin"
android:foregroundGravity="top"
android:layout_width="match_parent"/>
</android.support.design.widget.CollapsingToolbarLayout>
</android.support.design.widget.AppBarLayout>
</android.support.design.widget.CoordinatorLayout>
这是堆栈跟踪。正如您所看到的，原因在AppBarLayout中很深，并且有些误导。我首先想到这是由于NestedScrollView并继续工作，但经过大量的实验，结果却是ViewPager。另外，请忽略堆栈跟踪的intellij部分。在Android手机上运行时，它与顶部的堆栈跟踪基本相同。
java.lang.ClassCastException: android.widget.FrameLayout$LayoutParams cannot be cast to android.support.design.widget.CoordinatorLayout$LayoutParams
at android.support.design.widget.AppBarLayout$ScrollingViewBehavior.updateOffset(AppBarLayout.java:1155)
at android.support.design.widget.AppBarLayout$ScrollingViewBehavior.onDependentViewChanged(AppBarLayout.java:1150)
at android.support.design.widget.CoordinatorLayout.offsetChildToAnchor(CoordinatorLayout.java:1341)
at android.support.design.widget.CoordinatorLayout.dispatchOnDependentViewChanged(CoordinatorLayout.java:1109)
at android.support.design.widget.CoordinatorLayout$OnPreDrawListener.onPreDraw(CoordinatorLayout.java:1581)
at android.view.ViewTreeObserver.dispatchOnPreDraw(ViewTreeObserver.java:944)
at android.view.AttachInfo_Accessor.dispatchOnPreDraw(AttachInfo_Accessor.java:46)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.render(RenderSessionImpl.java:371)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:428)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:350)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:510)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:498)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:888)
at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:498)
at com.android.tools.idea.rendering.RenderTask.access$600(RenderTask.java:72)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:610)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:607)
at com.android.tools.idea.rendering.RenderService.runRenderAction(RenderService.java:366)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:607)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:629)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.doRender(AndroidLayoutPreviewToolWindowManager.java:652)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager.access$1700(AndroidLayoutPreviewToolWindowManager.java:80)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$7$1.run(AndroidLayoutPreviewToolWindowManager.java:594)
at com.intellij.openapi.progress.impl.CoreProgressManager$2.run(CoreProgressManager.java:152)
at com.intellij.openapi.progress.impl.CoreProgressManager.registerIndicatorAndRun(CoreProgressManager.java:452)
at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:402)
at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:54)
at com.intellij.openapi.progress.impl.CoreProgressManager.runProcess(CoreProgressManager.java:137)
at org.jetbrains.android.uipreview.AndroidLayoutPreviewToolWindowManager$7.run(AndroidLayoutPreviewToolWindowManager.java:589)
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$1.run(Alarm.java:351)
at java.util.concurrent.Executors$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)
答案 0 :(得分：1)
我不确定您将ViewPager放在AppBarLayout内的原因。它应该在AppBarLayout之外但在CoordinatorLayout之内。通过这个项目了解如何：https://github.com/chrisbanes/cheesesquare