The reason for the space is because your container layout (the layout into which the Fragment
is inflated) has paddings applied:
<LinearLayout
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/main_container"
android:layout_width="fill_parent"
android:layout_height="fill_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"
android:background="@color/mainBlue"
android:orientation="vertical" >
Remove the paddings at top, bottom, left and right and your Fragment
will take up all the space.