how to set top border for bottom navigation bar in android as shown in image

Question

is it possible to set top border for bottom navigation bar in android, if possible tell me how we can do this, i am using the new bottom navigation view of android. Here is my code

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
        <LinearLayout
            android:id="@+id/app_bar_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            android:layout_alignParentTop="true">
                <include
                    android:id="@+id/gamebar"
                    layout="@layout/gamebar_layout"
                    />
                <include
                    android:id="@+id/toolbar"
                    layout="@layout/toolbar_layout" />
        </LinearLayout>

        <!-- Let's add fragment -->
        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_below="@+id/app_bar_layout"
            android:layout_above="@+id/bottom_navigation"
            android:id="@+id/contentContainer"/>
        <android.support.design.widget.BottomNavigationView
            android:id="@+id/bottom_navigation"
            android:layout_width="match_parent"
            android:layout_height="56dp"
            android:layout_alignParentBottom="true"
            app:itemBackground="@color/BottomNavigationBgColor"
            app:itemIconTint="@color/CelestialBlue"
            app:itemTextColor="@color/CelestialBlue"
            app:menu="@menu/bottom_navigation_main" />
</RelativeLayout>

Answer 1

You can try this: add a View element above BottomNavigationView

<View
    android:layout_width="match_parent"
    android:layout_height="4dp"
    android:layout_above="@+id/bottom_navigation"
    android:background="#000000"></View>

<android.support.design.widget.BottomNavigationView
    android:id="@+id/bottom_navigation"
    android:layout_width="match_parent"
    android:layout_height="56dp"
    android:layout_alignParentBottom="true"
    app:itemBackground="@color/BottomNavigationBgColor"
    app:itemIconTint="@color/CelestialBlue"
    app:itemTextColor="@color/CelestialBlue"
    app:menu="@menu/bottom_navigation_main" />

Answer 2

1. Define a background drawable using XML:

   <layer-list xmlns:android="http://schemas.android.com/apk/res/android">
       <item>
           <shape android:shape="rectangle">
               <solid android:color="@color/colorPrimaryDark" />
           </shape>
       </item>
       <item android:top="1dp">
           <shape android:shape="rectangle">
               <solid android:color="@color/colorWhite" />
           </shape>
       </item>
   </layer-list>
   

2. Use it as background with

   android:background="@drawable/myBackgroundBottomDrawer"