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mandy Xun
2,917 PointsRending Problems
When I following the course "Build an Interactive Story App", I came across a error at the very beginning, when I want to run the emulator to check the first imageview, and the preview of the app is a blank white screen:
Rending Problems The following classes could not be instantiated: - android.support.v7.app.WindowDectorActionBar (Open Class, Show Exception, Clear Cache)
Tip: Use View.isInEditMode() in your custom views to skip code or show sample data when shown in the IDE
Exception Details: java.lang.NullPointerException at android.support.v7.app.WindowDecorActionBar.getDectorToolbar(WindowDecorAcationBar.java:241) at android.support.v7.app.WindowDecorActionBar.init(WindowDecorActionBar.java:198) at android.support.v7.app.WindowDecorActionBar.<init>(WindowDecorActionBar.java:190) at java.lang.reflect.Constructor.newInstance(Constructor.java.:513) at com.android.layoutlib.bridge.bars.AppCompatActionBar.<init>(AppCompatActionBar.java:89) at com.android.layoutlab.bridge.impl.Layout.createActionBar(Layout.java:237) at com.android.layoutlab.bridge.impl.Layout.<init>(Layout.java:151)
java.lang.NullPointerException at android.support.v7.app.WindowDecorActionBar.getDecorToolbar(WindowDecorActionBar.java:241) at android.support.v7.app.WindowDecorActionBar.init(WindowDecorActionBar.java:198) at android.support.v7.app.WindowDecorActionBar.<init>(WindowDecorActionBar.java:190) at sun.reflect.GeneratedConstructorAccessor209.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at org.jetbrains.android.uipreview.ViewLoader.createNewInstance(ViewLoader.java:458) at org.jetbrains.android.uipreview.ViewLoader.loadClass(ViewLoader.java:170) at org.jetbrains.android.uipreview.ViewLoader.loadView(ViewLoader.java:103) at com.android.tools.idea.rendering.LayoutlibCallbackImpl.loadView(LayoutlibCallbackImpl.java:168) at com.android.layoutlib.bridge.bars.AppCompatActionBar.<init>(AppCompatActionBar.java:89) at com.android.layoutlib.bridge.impl.Layout.createActionBar(Layout.java:237) at com.android.layoutlib.bridge.impl.Layout.<init>(Layout.java:151) at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:206) 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: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:362) 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:439) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918) at java.lang.Thread.run(Thread.java:695)