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Android Build an Interactive Story App (Retired) User Input Hiding the ActionBar with an App Theme

Posted by cesar real
cesar real
2,110 Points

App just doesn't work anymore after messing up with the Action Bar

I'm getting a message: Interactive Story has stopped after I run the emulator

the errors: E/AndroidRuntime: FATAL EXCEPTION: main Process: com.example.cesar.interactivestory, PID: 2608 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.cesar.interactivestory/com.example.cesar.interactivestory.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.app.ActionBar.hide()' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707) at android.app.ActivityThread.-wrap12(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460) at android.os.Handler.dispatchMessage(Handler.java:102) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6077) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.app.ActionBar.hide()' on a null object reference at com.example.cesar.interactivestory.MainActivity.onCreate(MainActivity.java:17) at android.app.Activity.performCreate(Activity.java:6662) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)  at android.app.ActivityThread.-wrap12(ActivityThread.java)  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)  at android.os.Handler.dispatchMessage(Handler.java:102)  at android.os.Looper.loop(Looper.java:154)  at android.app.ActivityThread.main(ActivityThread.java:6077)  at java.lang.reflect.Method.invoke(Native Method)  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)

Seth Kroger
Seth Kroger
56,413 Points
Seth Kroger
Seth Kroger
56,413 Points

Code? It looks like you didn't initialize your ActionBar variable properly before calling hide.