我一直在尝试使用AppBarLayout和折叠工具栏创建折叠工具栏。
一旦将AppBarLayout组件添加到项目中，布局编辑器便无法渲染，我注意到它也与其他一些组件（例如FAB）一起出现，但是一旦完成创建布局，我就可以删除FAB并添加它。错误仅出现在渲染中，当我运行该应用程序时，效果很好。
我尝试用默认的Scrolling活动创建一个新项目，该活动包含一个AppBarLayout和折叠式工具栏，并且该布局仍未呈现，并且仅在删除AppBarLayout之后才呈现，删除并添加它可能会暂时解决问题，但之后一些生成或更改问题会返回，并且布局不会再次在布局编辑器中呈现。
我试图通过单击文件->使缓存无效来解决该问题。它解决了片刻的问题，但是在添加了一些带有约束的约束之后，又再次出现了布局问题。
一些默认的滚动活动内容，包括应用栏布局和折叠工具栏
<com.google.android.material.appbar.AppBarLayout
android:id="@+id/app_bar"
android:fitsSystemWindows="true"
android:layout_height="@dimen/app_bar_height"
android:layout_width="match_parent"
android:theme="@style/AppTheme.AppBarOverlay">
<com.google.android.material.appbar.CollapsingToolbarLayout
android:id="@+id/toolbar_layout"
android:fitsSystemWindows="true"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:toolbarId="@+id/toolbar"
app:layout_scrollFlags="scroll|exitUntilCollapsed"
app:contentScrim="?attr/colorPrimary">
<androidx.appcompat.widget.Toolbar
android:id="@+id/toolbar"
android:layout_height="?attr/actionBarSize"
android:layout_width="match_parent"
app:layout_collapseMode="pin"
app:popupTheme="@style/AppTheme.PopupOverlay"/>
</com.google.android.material.appbar.CollapsingToolbarLayout>
</com.google.android.material.appbar.AppBarLayout>
The errors received:
java.lang.IllegalArgumentException: java.lang.ClassCastException@466d8fa7
at sun.reflect.GeneratedMethodAccessor738.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at android.animation.PropertyValuesHolder_Delegate.callMethod(PropertyValuesHolder_Delegate.java:108)
at android.animation.PropertyValuesHolder_Delegate.nCallFloatMethod(PropertyValuesHolder_Delegate.java:143)
at android.animation.PropertyValuesHolder.nCallFloatMethod(PropertyValuesHolder.java)
at android.animation.PropertyValuesHolder.access$400(PropertyValuesHolder.java:38)
at android.animation.PropertyValuesHolder$FloatPropertyValuesHolder.setAnimatedValue(PropertyValuesHolder.java:1387)
at android.animation.ObjectAnimator.animateValue(ObjectAnimator.java:990)
at android.animation.ValueAnimator.animateBasedOnTime(ValueAnimator.java:1339)
at android.animation.ValueAnimator.doAnimationFrame(ValueAnimator.java:1471)
at android.animation.AnimationHandler.doAnimationFrame(AnimationHandler.java:146)
at android.animation.AnimationHandler.access$100(AnimationHandler.java:37)
at android.animation.AnimationHandler$1.doFrame(AnimationHandler.java:54)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:947)
at android.view.Choreographer.doCallbacks(Choreographer.java:761)
at android.view.Choreographer_Delegate.doFrame(Choreographer_Delegate.java:66)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.renderAndBuildResult(RenderSessionImpl.java:563)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.render(RenderSessionImpl.java:425)
at com.android.layoutlib.bridge.BridgeRenderSession.render(BridgeRenderSession.java:120)
at com.android.ide.common.rendering.api.RenderSession.render(RenderSession.java:151)
at com.android.ide.common.rendering.api.RenderSession.render(RenderSession.java:133)
at com.android.tools.idea.rendering.RenderTask.lambda$null$8(RenderTask.java:755)
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1590)
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)
--------------------------------------------------
java.lang.IllegalArgumentException: java.lang.ClassCastException@1ff1f72c
at sun.reflect.GeneratedMethodAccessor738.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at android.animation.PropertyValuesHolder_Delegate.callMethod(PropertyValuesHolder_Delegate.java:108)
at android.animation.PropertyValuesHolder_Delegate.nCallFloatMethod(PropertyValuesHolder_Delegate.java:143)
at android.animation.PropertyValuesHolder.nCallFloatMethod(PropertyValuesHolder.java)
at android.animation.PropertyValuesHolder.access$400(PropertyValuesHolder.java:38)
at android.animation.PropertyValuesHolder$FloatPropertyValuesHolder.setAnimatedValue(PropertyValuesHolder.java:1387)
at android.animation.ObjectAnimator.animateValue(ObjectAnimator.java:990)
at android.animation.ValueAnimator.animateBasedOnTime(ValueAnimator.java:1339)
at android.animation.ValueAnimator.doAnimationFrame(ValueAnimator.java:1471)
at android.animation.AnimationHandler.doAnimationFrame(AnimationHandler.java:146)
at android.animation.AnimationHandler.access$100(AnimationHandler.java:37)
at android.animation.AnimationHandler$1.doFrame(AnimationHandler.java:54)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:947)
at android.view.Choreographer.doCallbacks(Choreographer.java:761)
at android.view.Choreographer_Delegate.doFrame(Choreographer_Delegate.java:66)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.renderAndBuildResult(RenderSessionImpl.java:563)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.render(RenderSessionImpl.java:425)
at com.android.layoutlib.bridge.BridgeRenderSession.render(BridgeRenderSession.java:120)
at com.android.ide.common.rendering.api.RenderSession.render(RenderSession.java:151)
at com.android.ide.common.rendering.api.RenderSession.render(RenderSession.java:133)
at com.android.tools.idea.rendering.RenderTask.lambda$null$8(RenderTask.java:755)
at java.util.concurrent.CompletableFuture$AsyncSupply.run(CompletableFuture.java:1590)
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)
材料组件1.1.0-alphax和当前稳定的Android Studio（在我的情况下为3.4.1）存在问题。尝试返回1.0.0版或下载Android Studio 3.5 Beta-x（我的版本为beta-04）。
答案 1 :(得分：0)
我必须通过单击文件->使缓存无效来解决该问题。它解决了片刻的问题，但在添加了一些约束后又再次出现了布局问题