java - Can't acces TextView defined in onCreate -

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• how declare textview variable can use anywhere? 2 answers

i still java beginner , have problem have onclick function , of course oncreate in define textview value. when want edit textview onclick can't that. know how can make textview value "global".

final textview result = (textview) findviewbyid(r.id.result); 

you have instantiate textview after setcontentview() method :

public class mainactivity extends activity {  textview textview;  @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);     textview = (textview)findviewbyid(r.id.textview); }  }