Scrolling TabHost+ViewPager inside a ScrollView

Question

I am using an ObservableScrollView as the parent layout and i am able to scroll the content depending on how i scroll the Parent(similar to Google I/O 2014 app). Everything was working as expected until i added the Tabhost with Viewpager as a child of ObservableScrollView. Now I am able to scroll the contents of Viewpager but not the Parent Scrollview. The Problem I think is with the focus. How can i make the Parent ObservableScrollViewScrollable along with Viewpager and Tabhost inside?

Thanks.

<com.rfit.views.ObservableScrollView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/scroll_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/WhiteSmoke"
android:fillViewport="true"
android:overScrollMode="never">

<FrameLayout
    android:id="@+id/scroll_view_child"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:clipChildren="false">

    <!-- Background photo -->
    <FrameLayout
        android:id="@+id/session_photo_container"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:foreground="@drawable/photo_banner_scrim">

        <ImageView
            android:id="@+id/session_photo"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:background="@color/LightGrey"


            android:scaleType="centerCrop" />
    </FrameLayout>

    <LinearLayout
        android:id="@+id/details_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@color/WhiteSmoke"
        android:clipToPadding="false"
        android:orientation="vertical"
        android:paddingLeft="@dimen/keyline_1"

        android:paddingRight="@dimen/keyline_1"
        android:paddingTop="16dp">









            <TabHost
                android:id="@android:id/tabhost"
                android:layout_width="match_parent"


                android:layout_height="wrap_content" >

                <LinearLayout
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"

                    android:orientation="vertical" >

                    <TabWidget
                        android:id="@android:id/tabs"
                        android:orientation="horizontal"
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_weight="0" />

                    <FrameLayout
                        android:id="@android:id/tabcontent"
                        android:layout_width="0dp"
                        android:layout_height="0dp"
                        android:layout_weight="0">


                    </FrameLayout>

                    <android.support.v4.view.ViewPager

                        android:id="@+id/viewpager"
                        android:layout_width="match_parent"
                        android:layout_height="match_parent"
                        android:layout_gravity="bottom" />







                </LinearLayout>
            </TabHost>







    </LinearLayout>

    <!-- Title/subtitle bar (floating; position determined at run time as the content view scrolls) -->
    <FrameLayout
        android:id="@+id/header_session"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:clipChildren="false"
        android:clipToPadding="false">

        <!-- height assigned dynamically -->
        <View
            android:id="@+id/header_background"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:background="@color/revofit_eat" />




        <LinearLayout
            android:id="@+id/header_session_contents"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="@color/revofit_eat"
            android:orientation="vertical"
            android:paddingBottom="16dp"
            android:paddingLeft="@dimen/keyline_2_session_detail"
            android:paddingRight="@dimen/keyline_1"
            android:paddingTop="16dp">

            <!-- Session title -->
            <TextView
                android:id="@+id/session_title"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_gravity="start"
                android:layout_marginBottom="0dp"
                android:ellipsize="end"
                android:fontFamily="@string/font_fontFamily_medium"
                android:lineSpacingMultiplier="1.1"
                android:maxLines="2"

                android:text="Bacon ipsum dolor sit amet chicken beef ribs kielbasa, tail bacon porchetta ground round voluptate sed aute shank meatball. Swine in andouille, ex esse duis fatback laboris ullamco frankfurter landjaeger. Beef ribs excepteur filet mignon meatloaf, jerky sausage esse beef meatball strip steak sint sunt et turducken bresaola. "
                android:textColor="@color/White"
                android:textSize="@dimen/text_size_large" />

            <!-- Session subtitle -->
            <TextView
                android:id="@+id/session_subtitle"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_gravity="start"
                android:ellipsize="end"
                android:maxLines="2"
                android:text="Dolor occaecat hamburger"
                android:textColor="@color/wallet_hint_foreground_holo_dark"
                android:textSize="16sp" />







        </LinearLayout>






        <View
            android:id="@+id/header_shadow"
            android:layout_width="match_parent"
            android:layout_height="6dp"

            android:layout_gravity="bottom"
            android:layout_marginBottom="-6dp"
            android:background="@drawable/bottom_shadow" />


    </FrameLayout>

    <!-- FAB -->
    <include layout="@layout/include_add_schedule_fab" />


</FrameLayout></com.rfit.views.ObservableScrollView>