expandablelistview - Java Illegal Argument Exception android -

i having kind of error, after searching possible resources still not work.

error:

java.lang.illegalargumentexception: view android.widget.expandablelistview{416b0bc8 vfed.vc. ......id 0,0-480,0 #7f080005 app:id/lvexp} not drawer  

heres code:

expandablelistadapter listadapter; expandablelistview explistview; list<string> listdataheader; private drawerlayout drawer; private linearlayout linear; button btn;  hashmap<string, list<string>> listdatachild;  @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_main);     preparelistdata();      btn = (button)findviewbyid(r.id.button1);     linear = (linearlayout)findviewbyid(r.id.linear);     explistview = (expandablelistview) findviewbyid(r.id.lvexp);     drawer = (drawerlayout)findviewbyid(r.id.drawer_layout);      btn.setonclicklistener(new view.onclicklistener() {          @override         public void onclick(view arg0) {             // todo auto-generated method stub         if(!drawer.isdraweropen(explistview))         {             drawer.opendrawer(explistview);         }         else         {             drawer.closedrawer(explistview);         }          }     });      // listview       // preparing list data       listadapter = new expandablelistadapter(this, listdataheader, listdatachild);      // setting list adapter     explistview.setadapter(listadapter); 

for xml:

<?xml version="1.0" encoding="utf-8"?> <linearlayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" android:background="#f4f4f4" >  <linearlayout     android:id="@+id/linear"     android:layout_width="match_parent"     android:layout_height="50dp"     android:background="#000000"     android:orientation="vertical" >      <linearlayout         android:layout_width="wrap_content"         android:layout_height="match_parent" >          <button             android:id="@+id/button1"             android:layout_width="47dp"             android:layout_height="45dp"             android:background="@drawable/ic_home" />     </linearlayout>      <linearlayout         android:layout_width="match_parent"         android:layout_height="match_parent"         android:gravity="center_vertical" >          <textview             android:id="@+id/textview1"             android:layout_width="wrap_content"             android:layout_height="wrap_content"             android:text="drawer"             android:textappearance="?android:attr/textappearancelarge" />     </linearlayout>      <android.support.v4.widget.drawerlayout          android:id="@+id/drawer_layout"         android:layout_width="match_parent"         android:layout_height="match_parent">         <!-- main content view -->         <framelayout             android:id="@+id/content_frame"             android:layout_width="match_parent"             android:layout_height="match_parent" />         <!-- navigation drawer -->           <expandablelistview             android:id="@+id/lvexp"             android:layout_width="match_parent"             android:layout_height="match_parent"             android:cachecolorhint="#00000000" >         </expandablelistview>     </android.support.v4.widget.drawerlayout>     </linearlayout>  </linearlayout> 

you getting exception on if(!drawer.isdraweropen(explistview)) explistview list not drawer. thats why getting java.lang.illegalargumentexception:

try post idea. more information link