How to add string to ListView dynamically in android? -

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public class myactivity extends activity {     context context;     list<string> tasks;     arrayadapter<string> adapter;      /**      * called when activity first created.      */     @override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.main);          context = this;         tasks = new arraylist<string>();          button add = (button) findviewbyid(r.id.button);         add.setonclicklistener(new view.onclicklistener() {             @override             public void onclick(view view) {                 edittext edittext = (edittext) findviewbyid(r.id.edittext);                 edittext.setvisibility(1);                  inputmethodmanager imm = (inputmethodmanager) getsystemservice(context.input_method_service);                 imm.showsoftinput(edittext, 0);                  string value = edittext.gettext().tostring();                 tasks.add(value);                  adapter = new arrayadapter<string>(context,r.id.listview,tasks);                 listview listview = (listview) findviewbyid(r.id.listview);                 listview.setadapter(adapter);             }         });     } }

here, getting value user. , trying add list view dynamically. but, showing error called "unfortunatly app closed". failing in adding string value tasks variable. tasks list of string.

tasks.add(value);

if try add else failing. like,

tasks.add("something");

i don't know problem. sure failing in line, because if remove line, app working fine. if knows why failing please let me know. in advance.

there many wrong in source code. try following code and, understand writing rather copy pasting blindly.

@override public void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.main);      context = this;     tasks = new arraylist<string>();      // instances variables on initial     button add = (button) findviewbyid(r.id.button);     final edittext edittext = (edittext) findviewbyid(r.id.edittext);      // second parameter row layout,      adapter = new arrayadapter<string>(context,android.r.layout.simple_list_item1,tasks);     listview listview = (listview) findviewbyid(r.id.listview);     listview.setadapter(adapter);        add.setonclicklistener(new view.onclicklistener() {         @override         public void onclick(view view) {              edittext.setvisibility(1);              inputmethodmanager imm = (inputmethodmanager) getsystemservice(context.input_method_service);             imm.showsoftinput(edittext, 0);              string value = edittext.gettext().tostring();             tasks.add(value);              // method refresh listview manually              adapter.notifydatasetchanged();         }     }); }

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