Android java : null context in a class that extend Application -


i have class extending application. when try context of class either using "getapplicationcontext" or using "getbasecontext", context allways null.

i need context use "getsharedpreferences".

the error printed :

caused by: java.lang.nullpointerexception @ android.content.contextwrapper.getapplicationcontext(contextwrapper.java:109)

what doing wrong or other ways can use "getsharedpreferences" without context (if possible) ?

thanks help.

edit code :

i'm initializing class "deviceinfo" in main class. class "deviceinfo" extends application. in it's constructor tried :

protected deviceinfo() {          context = getapplicationcontext(); }

wich gives me same error mentioned earlier.

and here main line causing me trouble...

sharedpreferences key = getapplicationcontext().getsharedpreferences("keys", context.mode_private);

final edit : all, took inputs , realized wasn't doing right way @ all. changed code , works, again.

your problem application's context hasn't been created before you're trying access it. ensure context has been created, should wait access context until oncreate() before attempting access context object.

for example:

public class deviceinfo extends application {      @override     public void oncreate() {         super.oncreate();         sharedpreferences key = getapplicationcontext().getsharedpreferences("keys", context.mode_private);     }  }

you can use preferencemanager.getdefaultsharedpreferences(getapplicationcontext()) access default preferences file.


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