Button overriding listview items and how to add textview just above listview

I have a listview between header and button, I want to add textview just above listview and button to align properly so that button do not override listview items. How can i do that? Not sure what is the issue with xml layout

layout.xml

<LinearLayout xmlns:android="http://ift.tt/nIICcg"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#e7ebee"
    android:gravity="center"
    android:orientation="vertical"
    android:weightSum="1">

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="452dp"
        android:layout_weight="1"
        android:gravity="center"
        android:orientation="vertical" >

        <RelativeLayout
            android:id="@+id/mainheader"
            android:layout_width="fill_parent"
            android:layout_height="52dp"
            android:background="#0a2436">

            <RelativeLayout
                android:id="@+id/subheader"
                android:layout_width="wrap_content"
                android:layout_height="52dp" >

                <ImageView
                    android:id="@+id/back"
                    android:layout_width="40dip"
                    android:layout_height="wrap_content"
                    android:layout_alignParentLeft="true"
                    android:layout_centerVertical="true"
                    android:background="@drawable/my_highlight_drawable"
                    android:src="@drawable/back" />

                <ImageView
                    android:id="@+id/inboxheader"
                    android:layout_width="2dip"
                    android:layout_height="wrap_content"
                    android:layout_centerVertical="true"
                    android:layout_marginRight="5dp"
                    android:layout_toRightOf="@+id/back"
                    android:background="#85929B"
                    android:paddingBottom="15dip"
                    android:paddingTop="15dip" />
            </RelativeLayout>

            <ImageView
                android:id="@+id/windowtitle"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerHorizontal="true"
                android:layout_centerVertical="true"
                android:contentDescription="@null"
                android:src="@drawable/logo" />
        </RelativeLayout>

        <ListView
            android:id="@android:id/list"
            android:layout_width="fill_parent"
            android:layout_height="match_parent"
            android:divider="@android:color/darker_gray"
            android:dividerHeight="1dip"
            android:drawSelectorOnTop="false"
            android:focusable="false"
            android:paddingTop="0dip" />

        <TextView
            android:id="@+id/android:empty"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:gravity="center"
            android:text="No Data Available"
            android:visibility="invisible" />
    </LinearLayout>

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:gravity="center" >

        <TableLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:layout_centerInParent="true"
            android:gravity="bottom">

            <TableRow
                android:layout_width="fill_parent"
                android:layout_height="wrap_content"
                android:background="#092435"
                android:gravity="center_horizontal" >

                <Button
                    android:id="@+id/btnManualLookup"
                    android:layout_width="0dp"
                    android:layout_weight="1"
                    android:background="#4982AE"
                    android:gravity="center"
                    android:padding="15dip"
                    android:text="Submit"
                    android:textColor="#ffffff" />


            </TableRow>
        </TableLayout>
    </LinearLayout>

</LinearLayout>