java - Android listview custom rows -

i have problem custom layout i've set listview. have button adds elements listview , uses custom row everytime try press button add crashes. can suggest solution on how fix this? i'm pretty new android btw.

here's code:

import android.app.activity; import android.content.intent; import android.os.bundle; import android.view.view; import android.widget.adapterview; import android.widget.arrayadapter; import android.widget.button; import android.widget.listadapter; import android.widget.listview;  import java.util.arraylist;  public class projectcreatescreen extends activity {  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.secondary_layout1);      button btn = (button) findviewbyid(r.id.addbtn);      final arraylist<string> listitems=new arraylist<string>();     final listadapter addadapter = new arrayadapter<string>(this, r.layout.custom_row,             listitems);     listview lv = (listview) findviewbyid(r.id.lv);     lv.setadapter(addadapter);      btn.setonclicklistener(new view.onclicklistener() {         @override         public void onclick(view v) {             listitems.add("new project");             ((arrayadapter) addadapter).notifydatasetchanged();         }     });     lv.setonitemclicklistener(new adapterview.onitemclicklistener() {         @override         public void onitemclick(adapterview<?> parent, view view, int position, long id) {             intent switchtoedit = new intent(projectcreatescreen.this, teamcreatescreen.class);             startactivity(switchtoedit);         }     }); } 

}

the layout activity uses:

<?xml version="1.0" encoding="utf-8"?> <relativelayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent" android:id="@+id/rl">  <button     android:layout_width="match_parent"     android:layout_height="60dp"     android:text="@string/addproject"     android:id="@+id/addbtn"     android:layout_alignparenttop="true"     android:layout_centerhorizontal="true"     android:onclick="startproject"/>  <listview     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:layout_below="@+id/addbtn"     android:id="@+id/lv">     </listview>  </relativelayout> 

the custom row layout:

<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical">  <textview     android:layout_width="wrap_content"     android:layout_height="80dp"     android:id="@+id/customrow"/>  </linearlayout> 

edit: need provide r.id.customrow arrayadapter constructor.

this should fix it:

 final listadapter addadapter = new arrayadapter<string>(this, r.layout.custom_row, r.id.customrow,                 listitems); 

with original code, added data arraylist, , got exception:

04-09 13:12:34.992  12418-12418/com.listviewtest.daniel.listviewtest e/arrayadapter﹕ must supply resource id textview 04-09 13:12:34.992  12418-12418/com.listviewtest.daniel.listviewtest d/androidruntime﹕ shutting down vm 04-09 13:12:34.992  12418-12418/com.listviewtest.daniel.listviewtest w/dalvikvm﹕ threadid=1: thread exiting uncaught exception (group=0x41891da0) 04-09 13:12:35.012  12418-12418/com.listviewtest.daniel.listviewtest e/androidruntime﹕ fatal exception: main     process: com.listviewtest.daniel.listviewtest, pid: 12418     java.lang.illegalstateexception: arrayadapter requires resource id textview