Tab's Are not Filling all the View

I have this layout but the problem that the tabs doesn't fill the screen like in this photo. I tried the tabgravity method but it doesn't exists in the tabwidget for my layout.

this is my layout.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.subhi.navtabs.MainActivity">


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



        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical">

            <HorizontalScrollView
                android:layout_width="match_parent"
                android:id="@+id/h_Scroll_View"
                android:layout_height="wrap_content">


                <TabWidget
                    android:id="@android:id/tabs"
                    android:fillViewport="true"
                    android:scrollbars="none"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"></TabWidget>

            </HorizontalScrollView>



            <FrameLayout
                android:id="@android:id/tabcontent"
                android:layout_width="match_parent"
                android:layout_height="match_parent">

                <android.support.v4.view.ViewPager
                    android:layout_width="match_parent"
                    android:id="@+id/viewpager"
                    android:layout_height="match_parent"></android.support.v4.view.ViewPager>
            </FrameLayout>
        </LinearLayout>
    </TabHost>
</RelativeLayout>

If anyone can Help me Please?

Use android.support.design.widget.TabLayout instead of TabHost. Here and here is a good tutorial how to use it properly. Then, you can use app:tabGravity="fill" to fill the view.