java - Null pointer exception on list view -

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• what nullpointerexception, , how fix it? 12 answers

i creating dynamic views. want add views list , remove them onactivityresult.

but getting nullpointerexception on list view when adding view list.

where should add view in list view?

here code :

public class mon extends fragment {      private framelayout fab;     private eventtablehelper mdb;     private intent i;     private viewgroup dayplanview;     private int minutesfrom,minutesto;     private list<eventdata> events;     private list<view> list;     private eventdata e;     private layoutinflater inflater;     public  boolean editmode;     private relativelayout container;     relativelayout parent;      view eventview;     @override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);          inflater = (layoutinflater) getactivity().getsystemservice(context.layout_inflater_service);     }     @override     public view oncreateview(layoutinflater inflater, viewgroup container,                              bundle savedinstancestate) {         view view = inflater.inflate(r.layout.fragment_mon, container, false);          fab = (framelayout) view.findviewbyid(r.id.main_fab);         imagebutton imagebutton = (imagebutton) view.findviewbyid(r.id.imgbtn_fab);        imagebutton.setonclicklistener(new view.onclicklistener() {             @override             public void onclick(view v) {                  = new intent(getactivity(), addeventactivity.class);                  editmode = false;                 i.putextra("editmode", editmode);                 startactivityforresult(i, 1);             }         });          dayplanview = (viewgroup) view.findviewbyid(r.id.hoursrelativelayout);          showevents();          return view;     }      private void createevent(layoutinflater inflater, viewgroup dayplanview, int fromminutes, int tominutes, string title,string location,final int id) {         eventview = inflater.inflate(r.layout.event_view, dayplanview, false);         relativelayout.layoutparams layoutparams = (relativelayout.layoutparams) eventview.getlayoutparams();          container = (relativelayout) eventview.findviewbyid(r.id.container);         textview tvtitle = (textview) eventview.findviewbyid(r.id.textviewtitle);           if (tvtitle.getparent() != null)            ((viewgroup) tvtitle.getparent()).removeview(tvtitle);          if(location.equals(""))         {             tvtitle.settext("event : " + title);         }         else         {             tvtitle.settext("event : " + title + " (at : " + location +")");         }         int distance = (tominutes - fromminutes);         layoutparams.topmargin = dptopixels(fromminutes + 9);         layoutparams.height = dptopixels(distance);          eventview.setlayoutparams(layoutparams);         dayplanview.addview(eventview);         container.addview(tvtitle);            eventview.setonclicklistener(new view.onclicklistener() {              @override             public void onclick(view v) {                  = new intent(getactivity(), addeventactivity.class);                 editmode = true;                 i.putextra("editmode", editmode);                 i.putextra("id", id);                 startactivityforresult(i, 1);              }         });     }      @override     public void onactivityresult(int requestcode, int resultcode, intent data) {         super.onactivityresult(requestcode, resultcode, data);          removeview();         showevents();     }      public void showevents()     {         mdb = new eventtablehelper(getactivity());         events = mdb.getallevents("mon");          (eventdata eventdata : events) {              int id = eventdata.getid();             string datefrom = eventdata.getfromdate();              if (datefrom != null) {                 string[] times = datefrom.substring(11, 16).split(":");                 minutesfrom = integer.parseint(times[0]) * 60 + integer.parseint(times[1]);             }             string title = eventdata.gettitle();             string location = eventdata.getlocation();             string dateto = eventdata.gettodate();              if (dateto != null) {                 //times = dateto.substring(11,16).split(":");                 string[] times1 = dateto.substring(11, 16).split(":");                 minutesto = integer.parseint(times1[0]) * 60 + integer.parseint(times1[1]);             }             createevent(inflater, dayplanview, minutesfrom, minutesto, title, location, id);             id++;              list.add(eventview);         }     }      public void removeview()     {         for(int i=0; i<list.size(); i++)         {             dayplanview.removeview(eventview);         }     }      private int dptopixels(int dp) {         return (int) (dp * getresources().getdisplaymetrics().density);     }  } 

getting exception @ list.add(eventview); please help..

your list never initialized , when come results trying add element null referenced list

solution:

in oncreate do:

list = new arraylist<view>();