Fix bottom bar in CoordinatorLayout

Try this layout :

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/container">

    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@+id/bottom_navigation"
        android:layout_alignParentTop="true">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">
        <android.support.v7.widget.CardView
            xmlns:card_view="http://schemas.android.com/apk/res-auto"
            android:id="@+id/card_view"
            android:layout_width="match_parent"
            android:layout_margin="10dp"
            android:layout_height="110dp"
            android:padding="15dp"
            card_view:cardElevation="2dp"
            card_view:cardCornerRadius="4dp">

            <TextView
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:text="Test" />

        </android.support.v7.widget.CardView>


        <android.support.v7.widget.CardView
            xmlns:card_view="http://schemas.android.com/apk/res-auto"
            android:id="@+id/card_view1"
            android:layout_width="match_parent"
            android:layout_margin="10dp"
            android:layout_height="110dp"
            android:padding="15dp"
            card_view:cardElevation="2dp"
            card_view:cardCornerRadius="4dp">

            <TextView
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:text="Test" />

        </android.support.v7.widget.CardView>

            <android.support.v7.widget.CardView
                xmlns:card_view="http://schemas.android.com/apk/res-auto"
                android:id="@+id/card_view3"
                android:layout_width="match_parent"
                android:layout_margin="10dp"
                android:layout_height="110dp"
                android:padding="15dp"
                card_view:cardElevation="2dp"
                card_view:cardCornerRadius="4dp">

                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:text="Test" />

            </android.support.v7.widget.CardView>

            <android.support.v7.widget.CardView
                xmlns:card_view="http://schemas.android.com/apk/res-auto"
                android:id="@+id/card_view4"
                android:layout_width="match_parent"
                android:layout_margin="10dp"
                android:layout_height="110dp"
                android:padding="15dp"
                card_view:cardElevation="2dp"
                card_view:cardCornerRadius="4dp">

                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:text="Test" />

            </android.support.v7.widget.CardView>

            <android.support.v7.widget.CardView
                xmlns:card_view="http://schemas.android.com/apk/res-auto"
                android:id="@+id/card_view5"
                android:layout_width="match_parent"
                android:layout_margin="10dp"
                android:layout_height="110dp"
                android:padding="15dp"
                card_view:cardElevation="2dp"
                card_view:cardCornerRadius="4dp">

                <TextView
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:text="Test" />

            </android.support.v7.widget.CardView>
        </LinearLayout>
    </ScrollView>


    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_gravity="bottom"
        android:gravity="bottom">

        <android.support.design.widget.BottomNavigationView
            android:layout_width="match_parent"
            android:layout_height="56dp"
            android:layout_weight="1"
            android:foregroundGravity="bottom"
            android:background="@color/green"
            app:itemIconTint="@color/white"
            app:itemTextColor="@color/white"
            android:id="@+id/bottomnav"
            app:menu="@menu/main">


        </android.support.design.widget.BottomNavigationView>

    </RelativeLayout>



</android.support.design.widget.CoordinatorLayout>