android报错，大神来看一下

求大神给我看一下

 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.anew/com.anew.MainActivity}: java.lang.IllegalStateException: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2688)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2749)
    at android.app.ActivityThread.-wrap12(ActivityThread.java)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1498)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:160)
    at android.app.ActivityThread.main(ActivityThread.java:6197)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:874)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:764)
Caused by: java.lang.IllegalStateException: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.
    at android.support.v7.app.AppCompatDelegateImplV9.setSupportActionBar(AppCompatDelegateImplV9.java:207)
    at android.support.v7.app.AppCompatActivity.setSupportActionBar(AppCompatActivity.java:130)
    at com.anew.MainActivity.onCreate(MainActivity.java:19)
    at android.app.Activity.performCreate(Activity.java:6736)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1119)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2641)
    ... 9 more

http://blog.csdn.net/zhaokaiqiang1992/article/details/47442691

由于Activity已存在ActionBar，所以使用Toolbar进行替换时出错.你可以换主题也可以增加values资源文件

楼上的链接讲的很详细了

是自定义theme时遇见的吗？你看看你的Activity是不是继承自app。。。Activity，改成继承自Activity