java - passing arrayList in Custom adapter -

i calling arraylist in customadapter, custom_row.xml contains desired row. want first 2 elements of arraylist side side in row, , third , fourth element in other row , on. wrote code, print first element arraylist. if remove comments , run, same error when putting comments. don't know going wrong.

or maybe should right way.

class customadapter extends arrayadapter {  list<string> names; layoutinflater inflater; context context; public customadapter(context context,  list<string> names) {     super(context,r.layout.custom_row ,names);    this.names=names;     this.context=context; }   @override public view getview(int position, view convertview, viewgroup parent) {      inflater=layoutinflater.from(getcontext());     view customview=inflater.inflate(r.layout.custom_row,parent,false);     string data=names.get(position);    //string data1=names.get(position+1);     textview tv=(textview)customview.findviewbyid(r.id.teama);     tv.settext(data);    //textview tv1=(textview)customview.findviewbyid(r.id.teamb);     //tv1.settext(data1);     return customview; } 

i getting error- java.lang.nullpointerexception: attempt invoke virtual method 'void android.widget.textview.settext(java.lang.charsequence)' on null object reference @ com.example.customadapter.getview

the problem because tv null, because findviewbyid(r.id.teama) returns null, so.. check teama exists in r.layout.custom_row