Có đọc tài liệu trên http://developer.android.com/guide/topics/ui/actionbar.html thấy v7 hỗ trợ actionbar từ android 2.1 mà khi tạo project android 2.3 thì nó báo deprecated ationbar.

Stack trace
java.lang.NoSuchFieldError: action_bar
at android.support.v7.internal.widget.ActionBarContainer.onFinishInflate(ActionBarContainer.java:83)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:814)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:64)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:782)
at android.view.LayoutInflater.rInflate_Original(LayoutInflater.java:809)
at android.view.LayoutInflater_Delegate.rInflate(LayoutInflater_Delegate.java:64)
at android.view.LayoutInflater.rInflate(LayoutInflater.java:782)
at android.view.LayoutInflater.inflate(LayoutInflater.java:504)
at android.view.LayoutInflater.inflate(LayoutInflater.java:414)
at com.android.layoutlib.bridge.bars.BridgeActionBar.(BridgeActionBar.java:84)
at com.android.layoutlib.bridge.bars.AppCompatActionBar.(AppCompatActionBar.java:56)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.createActionBar(RenderSessionImpl.java:1691)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:362)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:321)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:350)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:497)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:485)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:894)
at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:485)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:590)
at com.intellij.android.designer.designSurface.AndroidDesignerEditorPanel$6.run(AndroidDesignerEditorPanel.java:480)
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)

83% thành viên diễn đàn không hỏi bài tập, còn bạn thì sao?