When I disable my Spinner it looks almost exactly like it did prior to being disabled, i.e.
Before
I had a similar problem, except getChildView returned null for me, so the excepted solution did not work. I believe this was caused because I set the adapter in XML, and this ignored the "clickable" and "enabled" attributes.
This was my XML:
The solution for me was to remove the "enabled" and "clickable" attributes and put the following code in my "onCreate"
spinner.setEnabled(false);
Hope it helps someone!