NullPointerException in Opening Android Activity -

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this question has answer here:

when cast elements other layout got error.

final  spinner maining = (spinner) findviewbyid(r.id.spinner); final  edittext sub1 = (edittext) findviewbyid(r.id.sub1); final  edittext sub2 = (edittext) findviewbyid(r.id.sub2); final  edittext sub3 = (edittext) findviewbyid(r.id.sub3); final  edittext sub4 = (edittext) findviewbyid(r.id.sub4); final  edittext sub5 = (edittext) findviewbyid(r.id.sub5); final  edittext sub6 = (edittext) findviewbyid(r.id.sub6);

heres error

caused by: java.lang.nullpointerexception: attempt invoke virtual method 'android.view.view android.view.window.findviewbyid(int)' on null object reference

place code after setcontentview in activity.

if want them available in every method of activity, declare them fields.

public class myactivity extends activity {          spinner myspiner;        @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.my_layout);         myspiner = (spinner) findviewbyid(r.id.myspiner);

and instantiate them after.


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