Question

当我要创建toolbar的版式时，
然后显示此异常：

java.lang.ClassNotFoundException：android.view.View $ OnUnhandledKeyEventListener 在org.jetbrains.android.uipreview.ModuleClassLoader.load（ModuleClassLoader.java:180）在com.android.tools.idea.rendering.RenderClassLoader.findClass（RenderClassLoader.java:61）在org.jetbrains.android.uipreview.ModuleClassLoader.findClass（ModuleClassLoader.java:118）在java.lang.ClassLoader.loadClass（ClassLoader.java:424）在java.lang.ClassLoader.loadClass（ClassLoader.java:357）在org.jetbrains.android.uipreview.ModuleClassLoader.loadClass（ModuleClassLoader.java:213）在android.support.v7.widget.ViewUtils.isLayoutRtl（ViewUtils.java:58）在android.support.v7.widget.Toolbar.onMeasure_Original（Toolbar.java:1578）在android.support.v7.widget.Toolbar.onMeasure（Toolbar.java）在android.view.View.measure_Original（View.java:22071）在android.view.View_Delegate.measure（View_Delegate.java:80）在android.view.View.measure（View.java:22035）在android.view.ViewGroup.measureChildWithMargins（ViewGroup.java:6602）在android.widget.FrameLayout.onMeasure（FrameLayout.java:185）在android.view.View.measure_Original（View.java:22071）在android.view.View_Delegate.measure（View_Delegate.java:80）在android.view.View.measure（View.java:22035）在android.widget.RelativeLayout.measureChildHorizontal（RelativeLayout.java:715）在android.widget.RelativeLayout.onMeasure（RelativeLayout.java:461）在android.view.View.measure_Original（View.java:22071）在android.view.View_Delegate.measure（View_Delegate.java:80）在android.view.View.measure（View.java:22035）在com.android.layoutlib.bridge.impl.RenderSessionImpl.measureView（RenderSessionImpl.java:590）在com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate（RenderSessionImpl.java:343）在com.android.layoutlib.bridge.Bridge.createSession（Bridge.java:384）在com.android.tools.idea.layoutlib.LayoutLibrary.createSession（LayoutLibrary.java:193）在com.android.tools.idea.rendering.RenderTask.createRenderSession（RenderTask.java:544）在com.android.tools.idea.rendering.RenderTask.lambda $ inflate $ 3（RenderTask.java:678）在java.util.concurrent.FutureTask.run（FutureTask.java:266）在java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1142）在java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:617）在java.lang.Thread.run（Thread.java:745）

我正在使用Android API 28和Android Studio 3.1版

我的布局代码是：

<?xml version="1.0" encoding="utf-8"?> 
 <android.support.v7.widget.Toolbar 
   xmlns:android="schemas.android.com/apk/res/android"    
   android:layout_width="match_parent" 
   android:layout_height="wrap_content" 
   android:background="@color/colorPrimary" 
   android:id="@+id/main_app_bar" 
   android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" >     
 </android.support.v7.widget.Toolbar>

Answer 1

     xmlns:android="schemas.android.com/apk/res/android";   
remove semicolom(;) and try again

Answer 2

use this :


<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar

    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/colorPrimary"
    android:id="@+id/main_app_bar"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    xmlns:android="http://schemas.android.com/apk/res/android">
    </android.support.v7.widget.Toolbar>

创建工具栏时出现异常

2 个答案: