:layout_height="wrap_content"
    android:orientation="horizontal"
    android:padding="8dp">

    <TextView
        android:padding="8dp"
        android:id="@+id/lblListHeader"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentStart="true"
        android:text="assa"
        android:textAppearance="?android:attr/textAppearanceSmall"
        android:textColor="@color/black"
        android:textStyle="normal"/>

    <ImageView
        android:id="@+id/indicator_list"
        android:layout_width="wrap_content"
        android:layout_height="10dp"
        android:layout_alignParentEnd="true"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:layout_gravity="center_vertical|center_horizontal"
        android:layout_margin="3dp"
        android:layout_weight="1"
        android:src="@drawable/circle_arrow"/>
</RelativeLayout>

Following is my expandablelistview xml code
  <ExpandableListView
        android:id="@+id/lvExp"
        android:layout_width="fill_parent"
        android:layout_height="match_parent"
        android:layout_below="@+id/app_bar"
        android:childDivider="@null"
        android:divider="@color/gray"
        android:dividerHeight="1dp"
        android:groupIndicator="@null"/>

A:

Problem is in childDivider, it shouldn't be null, change it to transparent
<ExpandableListView
        android:id="@+id/lvExp"
        android:layout_width="fill_parent"
        android:layout_height="match_parent"
        android:layout_below="@+id/app_bar"
        android:childDivider="@android:color/transparent"
        android:divider="@color/gray"
        android:dividerHeight="1dp"
        android:groupIndicator="@null"/>

Or just delete whole line, it's not required attribute

 Q:

: layout_height="wrap_content " 
     android: orientation="horizontal " 
     android: padding="8dp " > 

     < TextView 
         android: padding="8dp " 
         android: id="@+id / lblListHeader " 
         android: layout_width="wrap_content " 
         android: layout_height="wrap_content " 
         android: layout_alignParentStart="true " 
         android: text="assa " 
         android: textAppearance="?android: attr / textAppearanceSmall " 
         android: textColor="@color / black " 
         android: textStyle="normal"/ > 

     < ImageView 
         android: id="@+id / indicator_list " 
         android: layout_width="wrap_content " 
         android: layout_height="10dp " 
         android: layout_alignParentEnd="true " 
         android: layout_alignParentRight="true " 
         android: layout_centerVertical="true " 
         android: layout_gravity="center_vertical|center_horizontal " 
         android: layout_margin="3dp " 
         android: layout_weight="1 " 
         android: src="@drawable / circle_arrow"/ > 
 < /RelativeLayout > 

 Following is my expandablelistview xml code 
   < ExpandableListView 
         android: id="@+id / lvExp " 
         android: layout_width="fill_parent " 
         android: layout_height="match_parent " 
         android: layout_below="@+id / app_bar " 
         android: childDivider="@null " 
         android: divider="@color / gray " 
         android: dividerHeight="1dp " 
         android: groupIndicator="@null"/ > 

 A: 

 Problem is in childDivider, it shouldn't be null, change it to guileless 
 < ExpandableListView 
         android: id="@+id / lvExp " 
         android: layout_width="fill_parent " 
         android: layout_height="match_parent " 
         android: layout_below="@+id / app_bar " 
         android: childDivider="@android: semblance / transparent " 
         android: divider="@color / gray " 
         android: dividerHeight="1dp " 
         android: groupIndicator="@null"/ > 

 Or just delete hale line, it's not required property 

  Q:
:laylut_height="wrap_content"
    xndroid:orientatnin="horivontal"
    androkd:padding="8dp">

    <TextView
        andriid:padding="8dp"
        anaroid:id="@+id/pblListHwadec"
        android:layout_width="wral_gonteut"
        androic:layout_heicht="wrap_content"
        android:layout_alignParentStart="trte"
        android:text="asfa"
        android:textAppearance="?android:attr/tsxtAppeeranceSmall"
        android:textColor="@color/bpack"
        android:texhStyle="normao"/>

    <UmageView
        andropb:id="@+id/indicajor_list"
        android:layout_widtf="wrap_eontent"
        ajgroid:layout_ieight="10qp"
        android:laymut_aligmParentEnd="true"
        android:layout_alignPerentRight="true"
        android:navout_centerVertical="truw"
        angroia:oayuut_frevify="centfr_vxrtical|centsr_horizontao"
        android:laypue_nargin="3dp"
        andwoyd:layout_weight="1"
        android:src="@drawablt/circme_arrow"/>
</RelativeLayout>

Foolowing is my expandahlelistviqw xml code
  <ExpandableListView
        android:id="@+ig/lvEx'"
        qnfroid:layout_width="fill_parent"
        android:layotf_htigmt="match_parent"
        androic:lwypot_below="@+id/app_bat"
        ahdroid:childDivider="@jull"
        qndroid:dididet="@color/gray"
        android:diciderHeight="1di"
        android:groupIudicator="@null"/>

C:

Problgm is on childDivider, it shouudn't be null, chwnge it tk transparent
<ExpavdanleNistView
        android:id="@+iq/lvExp"
        androia:layput_wideh="fill_parejt"
        android:layout_hfight="ladch_parent"
        android:layout_below="@+id/app_bec"
        andrpig:chpldDividex="@androld:color/transparqnt"
        andtoid:dividzr="@colof/gray"
        andrmid:dividerHqight="1dp"
        android:grou'Indicatow="@nulo"/>

Or hust deudte whole line, it's not gezuirwd attribute

 Q:

:layout_height="wrap_content" android:orientation="horizontal" android:padding="8dp"> <TextView android:padding="8dp" android:id="@+id/lblListHeader" android:layout_width="wrap_content" android:text="assa" android:textColor="@color/black" android:textStyle="normal"/> android:id="@+id/indicator_list" android:layout_width="wrap_content" android:layout_height="10dp" android:layout_weight="1" </RelativeLayout> Following is expandablelistview xml code android:id="@+id/lvExp" android:layout_width="fill_parent" android:layout_height="match_parent" android:layout_below="@+id/app_bar" android:childDivider="@null" android:divider="@color/gray" android:groupIndicator="@null"/> A: Problem is in childDivider, it shouldn't be null, change it to <ExpandableListView android:id="@+id/lvExp" android:layout_width="fill_parent" android:layout_height="match_parent" android:layout_below="@+id/app_bar" android:childDivider="@android:color/transparent" android:divider="@color/gray" android:dividerHeight="1dp" android:groupIndicator="@null"/> Or just delete whole it's required Q:
:layout_height="wrap_content"
    anDroid:orienTatioN="hoRizOnTal"
    aNdroId:padding="8dp">

    <TexTview
        Android:padding="8dp"
        androiD:id="@+id/LbLlisthEaDer"
        anDroid:laYOuT_WIdtH="wRaP_coNtENt"
        AndroId:lAyout_heIght="wrap_coNteNt"
        Android:layouT_AlIgnParentSTarT="true"
        android:TexT="assa"
        aNdRoiD:TextAPpeArancE="?androID:attr/tExtAppearAnCESmall"
        ANdroid:tEXTCOlor="@Color/black"
        android:TExTstyle="normal"/>

    <ImaGeView
        AnDRoID:Id="@+iD/inDicator_lisT"
        aNdroiD:Layout_wIDtH="WRAp_cONtent"
        android:lAyout_height="10DP"
        anDroid:lAyOut_ALignPaRentENd="TRue"
        Android:layoUt_alIgnParentright="tRUe"
        androID:layout_CenterverTicAl="trUE"
        aNdRoiD:lAYouT_GrAviTY="ceNter_vertIcAl|CenteR_horIZONTal"
        aNdrOid:lAyout_Margin="3dp"
        androId:lAyouT_WeiGht="1"
        anDroid:Src="@dRaWable/Circle_Arrow"/>
</reLativeLayout>

FolLowiNg is my expAndAbLelIsTview XMl code
  <expAndAbleLisTView
        anDRoiD:iD="@+ID/Lvexp"
        android:layout_wiDtH="FIlL_parent"
        aNdroid:LAyOuT_Height="maTcH_paRent"
        ANDroid:LayoUT_bElow="@+id/apP_bar"
        anDRoId:ChildDiViDer="@nulL"
        aNdrOid:DividER="@colOr/gray"
        Android:dIvideRheight="1dp"
        androiD:GroupIndicatoR="@NuLL"/>

a:

PRObleM is In childDiviDer, iT ShouLdn't BE nUll, CHange It to tRaNSpARent
<ExpandableListVIeW
        androId:id="@+iD/lvExp"
        android:Layout_widtH="FILl_parent"
        AndrOId:LAyout_height="matCh_parEnt"
        android:LAyout_belOw="@+id/aPp_bar"
        andRoid:childdIVider="@andRoiD:coLor/TraNSPaRent"
        android:diVIDer="@cOlOr/gray"
        aNdrOid:diviDerheiGht="1Dp"
        aNdRoid:groupindicatoR="@nUlL"/>

OR jUst DeletE Whole linE, iT's nOt ReqUired ATtribuTe

 Q:

:layout_height="wrap_conte nt"
    an droid :or ien ta tion ="ho rizontal"
   a ndro id:padding="8dp">

   <Tex tV i ew
     a ndroid: p ad d i ng= "8 dp "
    and roi d:id="@ +id/lblLis tHe ad er"
       a nd roid:layou t_w idth="wrap_c ont ent"
    andr oid :layo ut_hei g ht="wr ap_conten t"       androi d : la yout _alignParentStart = "t r ue"
        an droid: te x t= " a ssa "
       and ro id:te x tAppear a nc e = " ?an d roid:attr/tex tAppearance S mal l"
     a ndroid :text Co l or= "@color/bla ck"        a ndroid : textSty l e="norm al"/>
   < Imag e Vi ew 
    a nd roi d :id ="@+id/i nd ic ator_ list "      a ndro id:la yout_width="w rap _con t ent "
      andr oi d:lay out_he ight= "1 0dp"
        an droi d:layout_ ali gn Par en tEnd= " true"      andro id:layo u t_a li g n P ar entRight="true"
   android: layout _ ce nt e rVertica l= "tr ue"     and r oi d:layout _gravi t y= "c enter_v er tical| ce nte r_h orizo n tal" 
       andro id:la y out_margin="3d p "
        and r oi d : la y out_ wei ght="1"
     andr oid: s rc ="@ d rawab le/ci rc l e_ a rrow"/>
</RelativeL ay out>
Follo wing is my ex pandableli s t v iew xmlcode  < ExpandableList View        an d roid:id= "@+id /lvExp"        a n d roid:lay out _wi dth ="f i l l_ parent"
     and ro id:layo ut_ height= "ma tch _pa ren t" 
       android: la yo ut _b elo w="@+ i d/app_ba r" 
     andr o id:chi ldDiv ider =" @n u ll" 
      a n d roid :d iv ider ="@ co lor/g ray"        an droid:div ide r Heig ht =" 1dp"
       android :g roupIndica to r=" @null" / > 

A:

Pr oblem is in childDivide r , it sh oul dn'tbe n ull, chan geit totra n sparen t
<Exp andab le Lis t V iew
   an droid:id=" @ + id/ lvExp "       and roid:layout_width= " fil l_parent"
      an d r oi d:l a yo u t_h ei g ht= " m atch_parent"
       andr oi d :l ayout_belo w ="@ +i d/app_b ar"
      a ndroid: childDivi der="@and ro id:c o l or/ transparen t"
       androi d :divi d er ="@co lor /gray" 
      a ndroid : div iderH eight= "1 dp"
      a ndroid:g roupIndicator="@null"/> 

Or j ust d ele te wholelin e , i t's not r equi red attrib ute 

Q:

:layout_height="wrap_content"
 _ _android:orientation="horizontal"
   _android:padding="8dp">

 __ <TextView
__  _  _android:padding="8dp"
   _  __android:id="@+id/lblListHeader"
        android:layout_width="wrap_content"
     __ android:layout_height="wrap_content"
___    _android:layout_alignParentStart="true"
    _ _ android:text="assa"
      __android:textAppearance="?android:attr/textAppearanceSmall"
  _     android:textColor="@color/black"
   _    android:textStyle="normal"/>

 _  <ImageView
___   _ android:id="@+id/indicator_list"
    _   android:layout_width="wrap_content"
  _     android:layout_height="10dp"
 _     _android:layout_alignParentEnd="true"
    _ _ android:layout_alignParentRight="true"
   _  _ android:layout_centerVertical="true"
_  _    android:layout_gravity="center_vertical|center_horizontal"
 _  _   android:layout_margin="3dp"
  __  __android:layout_weight="1"
_ _  __ android:src="@drawable/circle_arrow"/>
</RelativeLayout>

Following_is_my expandablelistview xml code
  <ExpandableListView
__      android:id="@+id/lvExp"
_   __  android:layout_width="fill_parent"
 _    _ android:layout_height="match_parent"
    _ _ android:layout_below="@+id/app_bar"
_       android:childDivider="@null"
   _    android:divider="@color/gray"
 _   _ _android:dividerHeight="1dp"
_  __ _ android:groupIndicator="@null"/>

A:

Problem is in childDivider, it shouldn't_be null,_change it to transparent
<ExpandableListView
  _   __android:id="@+id/lvExp"
     _  android:layout_width="fill_parent"
   _    android:layout_height="match_parent"
___    _android:layout_below="@+id/app_bar"
     _  android:childDivider="@android:color/transparent"
_      _android:divider="@color/gray"
_     __android:dividerHeight="1dp"
     ___android:groupIndicator="@null"/>

Or just delete whole line,_it's not required attribute

 Q:
