에러 로그챗입니다 문제 해결좀 해주세요

Question

10-13 13:48:22.370 24077-24077/? E/AndroidRuntime: FATAL EXCEPTION: main
                                                   Process: com.example.user.myapplication, PID: 24077
                                                   java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.user.myapplication/com.example.user.myapplication.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:2917)
                                                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2978)
                                                       at android.app.ActivityThread.-wrap14(ActivityThread.java)
                                                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1628)
                                                       at android.os.Handler.dispatchMessage(Handler.java:102)
                                                       at android.os.Looper.loop(Looper.java:154)
                                                       at android.app.ActivityThread.main(ActivityThread.java:6646)
                                                       at java.lang.reflect.Method.invoke(Native Method)
                                                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1468)
                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1358)
                                                    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:204)
                                                       at android.support.v7.app.AppCompatActivity.setSupportActionBar(AppCompatActivity.java:129)
                                                       at com.example.user.myapplication.MainActivity.onCreate(MainActivity.java:20)
                                                       at android.app.Activity.performCreate(Activity.java:6912)
                                                       at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1126)
                                                       at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2870)
                                                       at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2978)
                                                       at android.app.ActivityThread.-wrap14(ActivityThread.java)
                                                       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1628)
                                                       at android.os.Handler.dispatchMessage(Handler.java:102)
                                                       at android.os.Looper.loop(Looper.java:154)
                                                       at android.app.ActivityThread.main(ActivityThread.java:6646)
                                                       at java.lang.reflect.Method.invoke(Native Method)
                                                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1468)
                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1358)

 

핸드폰에 어플 보내보는데 자꾸 앱 중지 뜨네요

원인과 해결방법좀 알려주세요

Answer 1

http://charactermail.tistory.com/134

참고해보세요.

Comments

android:theme="@style/AppTheme.NoActionBar"
이거를 입력하면 @style/AppTheme.NoActionBar이 부분이 빨간 글자로 되면서 오류가 떠요
Alt+Enter해도 뭘 해야 할지 모르겠어요

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에러나는덴 이유가 많아서..무슨 에러가 발생하는지 알아보셔용.
그리고 로그보니 MainActivity.java:20 번째 줄에서 에러났다는데 거기도 보시고요.
로그만 올리셔서 자세히는 답변을 못해드리겠네요;