android - How to populate a ListView with Parse Array using ArrayAdapter -

so i'm new android , i'm using parse backend. have array column in parse called prescriptionarray. want take contents of array (string values) , populate listview them. think i'm missing couple of lines not sure where? appreciated.. in advance!

public class prescriptionsarrayactivity extends appcompatactivity {  private listview lvprescriptions; private edittext etmedicalid; private arrayadapter<string> adapter ;   @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_prescriptions_array);      lvprescriptions = (listview) findviewbyid(r.id.lvprescriptions);     etmedicalid = (edittext) findviewbyid(r.id.etmedicalid);      //get medical id number previous activity     bundle bundle = getintent().getextras();     string str = bundle.getstring("medicalid");     toast.maketext(getbasecontext(), str, toast.length_long).show();     etmedicalid.settext(str);      final list<string> arrayprescription = new arraylist<string>();     final arrayadapter adapter = new arrayadapter(prescriptionsarrayactivity.this, android.r.layout.simple_list_item_1, arrayprescription);      final parsequery<parseobject> query = parsequery.getquery("prescriptionobject");     query.whereequalto("medicalid", etmedicalid.gettext().tostring());     query.findinbackground(new findcallback<parseobject>() {         public void done(list<parseobject> prescriptionlist, parseexception e) {              if (e == null) {                 (int = 0; < prescriptionlist.size(); i++) {                     parseobject p = prescriptionlist.get(i);                     if (p.getlist("prescriptionarray") != null) {                              string s = arrayprescription.tostring();                             adapter.addall(arrays.aslist(s));                       }                 }                 lvprescriptions.setadapter(adapter);             }             }         });     } }