Try this code,scroll view is from half way from button to onwards, lot of TextView are for checking scroll View.
<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"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<ScrollView
android:id="@+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignTop="@+id/button1"
android:layout_marginLeft="22dp"
android:layout_marginTop="20dp" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Large TextLarge TextLarge TextLarge
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text
Large TextLarge TextLarge TextLarge TextLarge Text"
android:textAppearance="?android:attr/textAppearanceLarge" />
</LinearLayout>
</ScrollView>
<Button
android:id="@+id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/scrollView1"
android:layout_alignParentTop="true"
android:layout_marginLeft="39dp"
android:layout_marginRight="39dp"
android:background="#ffff55"
android:text="Button" />
</RelativeLayout>