NoobCoder:

I'm trying to collapse my header view while scrolling up the view pager. In the following image relativelayout3 is the layout I want to collapse..

Something like playstore preview image collapse in app page..

I tried searching and the following line in relativelayout3, But it didnt work

app:layout_scrollFlags="scroll|enterAlways"

And this my complete xml,

    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:app="http://ift.tt/GEGVYd">
        android:layout_width="match_parent"
        android:layout_height="match_parent">
            android:layout_width="match_parent"
            android:layout_height="match_parent">
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:id="@+id/relativeLayout3"
                app:layout_scrollFlags="scroll|enterAlways"
                >
        android:layout_width="match_parent"
        android:layout_height="55dp"
        android:id="@+id/toolbar"
        android:background="@color/cornflower_blue_two"
        android:elevation="5dp">

            android:id="@+id/more"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentEnd="true"
            android:layout_centerVertical="true"
            android:layout_marginEnd="10dp"
            android:background="@null"
            android:src="@drawable/ic_dots_vertical" />

            android:id="@+id/back"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentStart="true"
            android:layout_centerVertical="true"
            android:layout_marginEnd="5dp"
            android:layout_marginStart="10dp"
            android:background="@null"
            android:src="@drawable/ic_arrow_left" />


        android:id="@+id/slider"
        android:layout_width="match_parent"
        android:layout_height="250dp"
        android:background="@color/blue"
        android:layout_below="@id/toolbar"
        />


                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_alignParentStart="true"
                android:layout_below="@+id/relativeLayout3">

                    android:id="@+id/product"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_margin="10dp"
                    android:text="Blah Blah"
                    android:textColor="@color/dark_gray"
                    android:textSize="25sp"
                    android:textStyle="bold" />

                    android:id="@+id/brand"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignStart="@+id/product"
                    android:layout_below="@+id/product"
                    android:text="Blah inc."
                    android:textSize="20sp"
                    android:textStyle="bold" />

                    android:id="@+id/ratings"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignBaseline="@+id/brand"
                    android:layout_alignBottom="@+id/brand"
                    android:layout_marginStart="10dp"
                    android:layout_toEndOf="@+id/brand"
                    android:background="@color/ratings"
                    android:paddingEnd="10dp"
                    android:paddingStart="10dp"
                    android:text="4.7"
                    android:textColor="@color/white"
                    android:textSize="20sp"
                    android:textStyle="bold" />

                                    android:id="@+id/tabLayout"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_alignParentStart="true"
                    android:layout_below="@+id/brand"
                    android:layout_marginTop="14dp"
                    app:tabGravity="fill"
                    app:tabMode="fixed" />

                                    android:id="@+id/pager"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_alignParentStart="true"
                    android:layout_below="@+id/tabLayout" />