How to Make a Custom Overlay View Transparent on top of a SurfaceView?

Question

OK I've gone through many similar questions here on SO and around the web, to no avail. I'm just trying to overlay a transparent view on top of a SurfaceView.. and eventually draw a rectangle on it, such that it appears to overlay the camera preview.

I cannot get the custom view to be transparent, it blocks-out the underlying camera preview. Any suggestions?

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <FrameLayout 
        android:layout_alignParentTop="true"
        android:layout_width="fill_parent"
        android:layout_height="400dip">
        <SurfaceView
            android:layout_width="fill_parent"
            android:layout_height="fill_parent" 
            android:id="@+id/drawSurface"  />
        <com.bobby.facecapture.FaceOverlayView
            android:id="@+id/drawOverlay"
            android:background="@android:color/transparent" 
            android:layout_width="200dip"     
            android:layout_height="200dip"    
        />
    </FrameLayout>
</RelativeLayout>

The 200x200 is just temporary, to prove that it is indeed overlaying the other view.

The FaceOverlayView is just a custom view - deriving directly from View, without overriding anything (for now).

I get a black rectangle on top of the camera preview

Answer 1

Well, this resource file is the Barcode Scanner capture layout, which has a "viewfinder" layered over top of a camera preview. They use their own @color/transparent resource, defined as <color name="transparent">#00000000</color>. Perhaps poke around with their code and try to figure out where you and they differ.