I guess I am using incompatible themes
Code:
  --------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
                  Process: com.example.naveen.materialthemeapp, PID: 2366
                  java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.naveen.materialthemeapp/com.example.naveen.materialthemeapp.MainActivity}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2325)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387)
                      at android.app.ActivityThread.access$800(ActivityThread.java:151)
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303)
                      at android.os.Handler.dispatchMessage(Handler.java:102)
                      at android.os.Looper.loop(Looper.java:135)
                      at android.app.ActivityThread.main(ActivityThread.java:5254)
                      at java.lang.reflect.Method.invoke(Native Method)
                      at java.lang.reflect.Method.invoke(Method.java:372)
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
                   Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
                      at android.support.v7.app.AppCompatDelegateImplV9.createSubDecor(AppCompatDelegateImplV9.java:355)
                      at android.support.v7.app.AppCompatDelegateImplV9.ensureSubDecor(AppCompatDelegateImplV9.java:324)
                      at android.support.v7.app.AppCompatDelegateImplV9.setContentView(AppCompatDelegateImplV9.java:285)
                      at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:140)
                      at com.example.naveen.materialthemeapp.MainActivity.onCreate(MainActivity.java:11)
                      at android.app.Activity.performCreate(Activity.java:5990)
                      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1106)
                      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2278)
                      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2387) 
                      at android.app.ActivityThread.access$800(ActivityThread.java:151) 
                      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1303) 
                      at android.os.Handler.dispatchMessage(Handler.java:102) 
                      at android.os.Looper.loop(Looper.java:135) 
                      at android.app.ActivityThread.main(ActivityThread.java:5254) 
                      at java.lang.reflect.Method.invoke(Native Method) 
                      at java.lang.reflect.Method.invoke(Method.java:372) 
                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903) 
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698) 
Application terminated.

what should I do to avoid this error should I download a older version or there is a work around for this one