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Timothy Boland
18,237 PointsReceiving SharedPreferences.getString(java.lang.String, java.lang.String)' on a null object reference
I get the following error when running the app:
07-10 17:33:06.208 1474-1474/com.racecondtion.android.retrofitworkshop E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.racecondtion.android.retrofitworkshop, PID: 1474
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.racecondtion.android.retrofitworkshop/com.racecondtion.android.retrofitworkshop.MainActivity}: java.lang.NullPointerException: Attempt to invoke interface method 'java.lang.String android.content.SharedPreferences.getString(java.lang.String, java.lang.String)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2416)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Caused by: java.lang.NullPointerException: Attempt to invoke interface method 'java.lang.String android.content.SharedPreferences.getString(java.lang.String, java.lang.String)' on a null object reference
at com.racecondtion.android.retrofitworkshop.api.OAuthUtil.get(OAuthUtil.java:40)
at com.racecondtion.android.retrofitworkshop.api.OAuthUtil.isAuthorized(OAuthUtil.java:56)
at com.racecondtion.android.retrofitworkshop.MainActivity.onCreate(MainActivity.java:61)
at android.app.Activity.performCreate(Activity.java:6251)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1107)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2369)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2476)
at android.app.ActivityThread.-wrap11(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1344)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
Seems like its not getting any data from OAuthUtil.isAuthorized I think the lesson is missing some code. I noticed the code that sets OAuthUtil is in onResume, not onCreate or onStart, so maybe that is why the values are null. Did anyone else have this problem?
1 Answer
Timothy Boland
18,237 PointsThis question was for the "Simplify Networking with RetroFit" android course. I was getting this error because i didnt have my BaseApplication class in the Android Manifest...Everything is good now