Unexpected error in android app

Question

I made a small app in android studio, which is tic tac (XO) game. All was working fine and I've tested the app on the emulator many times. But at a moment the application crashed and the well known message says: Unfortunately, "tictactoe has stopped". And then I wasn't even able to start the app, all the time it crashes when trying to run it.

Android logcat showed those messages:

E/AndroidRuntime: FATAL EXCEPTION: main
E/AndroidRuntime: java.lang.RuntimeException: Unable to resume activity {.tictactoe/.tictactoe.MainGame}: java.lang.NullPointerException
E/AndroidRuntime: at android.app.ActivityThread.performResumeActivity(ActivityThread.java:2575)
E/AndroidRuntime: at android.app.ActivityThread.handleResumeActivity(ActivityThread.java:2603) E/AndroidRuntime: at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2089) E/AndroidRuntime: at android.app.ActivityThread.access$600(ActivityThread.java:130)

With many more messages. Any help?

Update: more logcat:

E/AndroidRuntime: at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:99) E/AndroidRuntime: at android.os.Looper.loop(Looper.java:137)

please post your complete Logcat and the relevant code too.. — Lal, Jan 22 '16 at 16:36
from your logcat that is posted, i can understand that the Null pointer exception is raised in your `onResume()`. — Lal, Jan 22 '16 at 16:38
@Lal I tryed to post the complete logcat, put the stackoverflow wditor refused it! — Ahmad Issa, Jan 22 '16 at 16:46
my problem is that the app worked fine, and then crashed without even editing my code! — Ahmad Issa, Jan 22 '16 at 16:47
sorry onResume have some code: protected void onResume() { super.onResume(); IsBackGround = false; mPlayer.start(); } — Ahmad Issa, Jan 22 '16 at 16:57
may be `IsBackGround ` or `mPlayer` is null..show your code please.. — Lal, Jan 22 '16 at 17:06
@Lal and Knossos and every one, I solved the problem, the issue was with null pointer to Media player, some code may be deleted by mistake or so, and that lead to NULL pointer exception. Thank you for help! — Ahmad Issa, Jan 22 '16 at 17:08
It's always good to catch the exceptions and print the stack traces to debug more efficiently. — Mohit Sharma, Jan 22 '16 at 18:20

score 0 · Answer 1 · answered Jan 22 '16 at 16:47

You need to use saveBundleState and onResumeBundleState to hold important view items information. You likely have elements in the main activity OnCreate which use generated views/items right?

You also need to make sure this is present:

onPause(){
super.onPause;
//DO SOME CODE TO SAVE BUNDLE
}

onResume(){
super.onResume;
//DO SOME CODE TO REOPEN BUNDLE
}

Unexpected error in android app

1 Answers1