android - Can't read text file from assets with button click -

i've seen question common, after searching couldnt figure out solution problem: goal read simple text file assets when button clicked. i've followed tutorial, adapted project, when button clicked, nothing happens, although file in right place. here's code , in advance:

public class resultactivity extends activity implements view.onclicklistener {  button restart; button answers; textview ler; textview msg;   @override   protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_result);     getwindow().setflags(windowmanager.layoutparams.flag_fullscreen, windowmanager.layoutparams.flag_fullscreen);      msg = (textview) findviewbyid(r.id.msg);     ler=(textview) findviewbyid(r.id.ler);     answers=(button) findviewbyid(r.id.answers);     answers.setonclicklistener(this);     restart=(button) findviewbyid(r.id.restartquiz);     restart.setonclicklistener(this);      msg.settext("correct answers: " + quizactivity.correct + "wrong answers: "             + quizactivity.wrong + " final score " + quizactivity.score);   }  @override public void onclick(view view) {     if (view == restart) {          quizactivity.score=0;         quizactivity.correct=0;         quizactivity.wrong=0;         intent = new intent(this, mainactivity.class);         startactivity(a);     }     if(view==answers){         string text="";         try{             inputstream is= getassets().open("file.txt");             int size=is.available();             byte [] buffer=new byte[size];             is.read(buffer);             is.close();         }catch (ioexception e){             e.printstacktrace();         }         ler.settext(text);     }   }   public void onbackpressed() {    } } 

this code may class implementation provided android system. allows access application-specific resources , classes. return assetmanager instance application's package.

public class resultactivity extends activity implements view.onclicklistener {   button restart;  button answers;  textview ler;  textview msg;   @override  protected void oncreate(bundle savedinstancestate) {  super.oncreate(savedinstancestate);  setcontentview(r.layout.activity_result);  getwindow().setflags(windowmanager.layoutparams.flag_fullscreen, windowmanager.layoutparams.flag_fullscreen);  msg = (textview) findviewbyid(r.id.msg); ler=(textview) findviewbyid(r.id.ler); answers=(button) findviewbyid(r.id.answers); answers.setonclicklistener(this); restart=(button) findviewbyid(r.id.restartquiz); restart.setonclicklistener(this);  msg.settext("correct answers: " + quizactivity.correct + "wrong answers: "         + quizactivity.wrong + " final score " + quizactivity.score);   }   @override  public void onclick(view view) {  if (view == restart) {      quizactivity.score=0;     quizactivity.correct=0;     quizactivity.wrong=0;     intent = new intent(this, mainactivity.class);     startactivity(a);    }    if(view==answers){     string text="";     try{ assetmanager text = mycontext.getassets();     inputstream = text.open("file.txt");         inputstream is= getassets().open("file.txt");         int size=is.available();         byte [] buffer=new byte[size];         is.read(buffer);         text = new string(buffer, 0, size); //this line missing          is.close();     }catch (ioexception e){         e.printstacktrace();     }     ler.settext(text);   } }  public void onbackpressed() {   } }