android - setting strings equal to eachother in a popup -

i'm making type of calculator app calculates surface areas of weird shapes etc.. when measurements inputted, user clicks calculate,and result gets displayed. problem i'm having cant result string (z) equal 1 in popup... dearly appreciated because have been stuck on quite while now.

public class rectangular extends activity {  edittext length; edittext width; edittext edge; edittext roll; textview tt; button calculate; double w=0; double x=0; double y=0; double z=0; double v=0;   @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_rectangular);     initcontrols();      //when calculation done, popup window inflates      final button btnopenpopup = (button)findviewbyid(r.id.button8);     btnopenpopup.setonclicklistener(new button.onclicklistener() {         public void onclick(view arg0) {             layoutinflater layoutinflater                     = (layoutinflater) getbasecontext()                     .getsystemservice(layout_inflater_service);             view popupview = layoutinflater.inflate(r.layout.pop_up, null);             final popupwindow popupwindow = new popupwindow(                     popupview,                     viewgroup.layoutparams.fill_parent,                     viewgroup.layoutparams.fill_parent);             popupwindow.showatlocation(popupview, gravity.center, 0, 0);             edittext rs = (edittext) popupview.findviewbyid(r.id.edittext6);             rs.settext(double.tostring(z));               button btndismiss = (button) popupview.findviewbyid(r.id.button9);             btndismiss.setonclicklistener(new button.onclicklistener() {                  @override                 public void onclick(view v) {                     // todo auto-generated method stub                     popupwindow.dismiss();                 }             });              popupwindow.showasdropdown(btnopenpopup, 50, -30);          }     });  }   //these initial controls calculation gets put string z  private void initcontrols() {     length=(edittext)findviewbyid(r.id.edittext);     width=(edittext)findviewbyid(r.id.edittext2);     edge=(edittext)findviewbyid(r.id.edittext3);     roll=(edittext)findviewbyid(r.id.edittext4);     tt=(textview)findviewbyid(r.id.edittext5);     calculate=(button)findviewbyid(r.id.button8);     calculate.setonclicklistener(new button.onclicklistener() {public void onclick                 (view v) { calculate();}}); }  edittext input; edittext output; button one;   private void calculate() {       w=double.parsedouble(length.gettext().tostring());     x=double.parsedouble(width.gettext().tostring());     y=double.parsedouble(edge.gettext().tostring());     v=double.parsedouble(roll.gettext().tostring());     z=((x+y+y)*(y+y+w))/v;          }     public void clear (view v){     viewgroup group = (viewgroup) findviewbyid(r.id.scrollview);     clearform(group); }  private void clearform(viewgroup group) {     (int = 0, count = group.getchildcount(); < count; ++i) {         view view = group.getchildat(i);         if (view instanceof edittext) {             ((edittext)view).settext("");         }          if(view instanceof viewgroup && (((viewgroup)view).getchildcount() > 0))             clearform((viewgroup)view);     } }     @override public boolean oncreateoptionsmenu(menu menu) {     // inflate menu; adds items action bar if present.     getmenuinflater().inflate(r.menu.menu_rectangular, menu);     return true; }  @override public boolean onoptionsitemselected(menuitem item) {     // handle action bar item clicks here. action bar     // automatically handle clicks on home/up button, long     // specify parent activity in androidmanifest.xml.     int id = item.getitemid();      //noinspection simplifiableifstatement     if (id == r.id.action_settings) {         return true;     }      return super.onoptionsitemselected(item); } 

}