android - Can't remove "shadow" from unelevated transparent FloatingActionButton -

after spending multiple hours researching problem, decided ask instead of wasting more time on such (seemingly) easy task.

i'm trying implement floatingactionbutton transparent background , no broder, show custom icon. know material design discourages it, need way.

the problem face there shadow showing, don't want. since set elevation 0dp don't know how got there , how can remove it.

here code fragment containing fab:

<android.support.design.widget.coordinatorlayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/fragment_layout" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@drawable/bg_sample" android:elevation="0dp" android:fitssystemwindows="true">      <android.support.v7.widget.recyclerview         android:id="@+id/fragment_grid"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:fitssystemwindows="true"         android:gravity="center"         android:padding="10dp"         android:stretchmode="columnwidth"         android:verticalspacing="25dp"/>      <android.support.design.widget.floatingactionbutton         android:id="@+id/fab"         style="@style/apptheme"         android:layout_width="wrap_content"         android:layout_height="wrap_content"         android:layout_gravity="bottom|center"         android:layout_marginbottom="@dimen/activity_vertical_margin"         android:adjustviewbounds="true"         android:elevation="0dp"         android:fitssystemwindows="true"         android:scaletype="fitcenter"         app:borderwidth="0dp"         app:fabsize="normal"         app:layout_anchorgravity="bottom|center"         app:layout_behavior="scrollawarefabbehavior"         />  </android.support.design.widget.coordinatorlayout> 

here apptheme:

<style name="apptheme" parent="theme.appcompat.light.darkactionbar">     <item name="colorprimary">@color/colorprimary</item>     <item name="colorprimarydark">@color/colorprimarydark</item>     <item name="coloraccent">@color/coloraccent</item>     <item name="android:fitssystemwindows">true</item>     <item name="android:spotshadowalpha">0</item>     <item name="android:shadowradius">0</item>     <item name="android:ambientshadowalpha">0</item>     <item name="selectableitembackgroundborderless">@null</item> </style> 

the oncreateview of fragment in set transperancy:

@override public final view oncreateview(final layoutinflater inflater, final viewgroup container,                                final bundle savedinstancestate) {     // initialize variables     view view = inflater.inflate(r.layout.fragment_desk, container, false);      coordinatorlayout = (coordinatorlayout) view.findviewbyid(r.id.fragment_layout);     fab = (floatingactionbutton) coordinatorlayout.findviewbyid(r.id.fab);     fab.getbackground().setcolorfilter(color.transparent, porterduff.mode.clear);      return view; } 

tl;dr: how can remove shadow shown in second picture?

edit: seems, problem linked fab size. set design_fab_size_normal 200 see, does. turns out doesn't affect icon size size of shadow.

here dimens.xml:

<resources xmlns:tools="http://schemas.android.com/tools">     <dimen name="design_fab_image_size" tools:override="true">64dp</dimen>     <dimen name="design_fab_size_normal" tools:override="true">200dp</dimen> </resources> 

it should be:

app:elevation="0dp" 

instead of:

android:elevation="0dp" 

you can java code using:

float zeroelevation=0.0f; view.setelevation(zeroelevation);