nullpointerexception - Android Crash after using SharedPreferences -


i developing android application, keep me logged in functionality using sharedpreferences application started crash.

this line add preferences;

sharedpreferences pref = getapplicationcontext().getsharedpreferences("rs_remember" , getapplicationcontext().mode_private);

i pretty sure line causing error because works fine if remove it.

error message says:

java.lang.runtime: unable create application com.x.x.x : java.lang.nullpointerexception.

any idea abot shuold do?

edit

public activity activity;     sharedpreferences pref;     private rscurrentusermanager()     {         super();              pref = this.activity.getsharedpreferences("rallyspark_remember",0);       }   +05-09 18:02:56.221: e/androidruntime(31760): fatal exception: main +05-09 18:02:56.221: e/androidruntime(31760):  java.lang.runtimeexception: unable create application  com.x.x.general.rsapplication:  java.lang.nullpointerexception +05-09 18:02:56.221:  e/androidruntime(31760):   @  com.x.x.general.rscurrentusermanager.<init>(rscurrentusermanager.java:93) +05-09 18:02:56.221: e/androidruntime(31760):   @ com.x.x.general.rscurrentusermanager.getinstance(rscurrentusermanager.java:84)

i not using shared preferences in other pleace in order find problem removed execpt defination

if inside of activity method shouldn't need use context. if aren't or inside of inner class or listener replcae

sharedpreferences pref = getapplicationcontext().getsharedpreferences("rs_remember" , getapplicationcontext().mode_private);

with

sharedpreferences pref = activityname.this.getsharedpreferences("rs_remember" , getapplicationcontext().mode_private);

most of time want use activity context instead of application context. can find many posts information 2 on so. i'm pretty sure problem if isn't please post full logcat , show line in code.

this answer has explanation of two


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