Stretching ImageView to fill screen height inside of Horizontal Scroll View

I've read all there is to read in terms of supporting different screen desnities. And, I have supplied proper variations of the images being display to appropriate folders. However, I am bewildered by something. The documentation for ImageView says that setting android:layout_width and android:layout_height to "fill_parent"/"match_parent" will result in the image stretching to fill the screen. (This seems necessary since not all screen densities offer the same size/pixel count screens and I don't want those extra few pixels to result in padding on the bottom of the screen) This seems to work any other time, but is not working for me when the ImageView is placed inside of a Horizontalscrollview and the width of the image is longer than that of the screen.

My code below: (The activity is set to landscape in my manifest)

<HorizontalScrollView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/hscrollview"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="0dp"
    android:fadingEdge="none"
    android:scrollbars="none"
    android:overScrollMode="never" >

<RelativeLayout 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:padding="0dp"
    android:fadingEdge="none"
    android:scrollbars="none"
    android:overScrollMode="never" >

<ImageView
    android:id="@+id/MapImageView"
    android:src="@drawable/map"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent" />
</RelativeLayout>
</HorizontalScrollView>

Edit: I replaced :src with :background to no effect.

This is the effect I get on devices like tablets. Ideally I want the image to fill the entire screen, like it does, below, on a phone with typical 480x800 resolution or the like.

Try using android:scaleType="fitXY" in your ImageView.