persistent_bottomsheet.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/bottomsheet"
    android:layout_width="match_parent"
    android:layout_height="300dp"
    android:layout_alignParentBottom="true"
    android:background="#636262"
    android:orientation="vertical"
    app:behavior_hideable="false"
    app:behavior_peekHeight="50dp"
    app:layout_behavior="android.support.design.widget.BottomSheetBehavior">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:orientation="horizontal">

        <TextView
            android:id="@+id/cart"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:layout_alignParentTop="true"
            android:onClick="ExpandBottomSheet"
            android:text="CART"
            android:padding="5dp"
            android:gravity="center"
            android:textStyle="bold"
            android:textColor="@android:color/black" />

        <TextView
            android:id="@+id/pay"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="PAY"
            android:padding="5dp"
            android:textStyle="bold"
            android:onClick="pay"
            android:textColor="@android:color/black"
            android:gravity="center_vertical"
            android:layout_alignParentRight="true" />

    </RelativeLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center_vertical"
        android:orientation="horizontal">
        <android.support.v7.widget.RecyclerView
            android:id="@+id/recyclerview_bottom_sheet"
            android:layout_width="match_parent"
            android:layout_height="match_parent"></android.support.v7.widget.RecyclerView>
    </LinearLayout>
</LinearLayout>