ImageView displaying in layout but not on actual device

Question

I have an ImageView that I want to display matching the full width of the device, I realized that like this:

Answer 1

I had a problem with a samsung phone not displaying my drawable but it worked fine on another phone. The picture was not in any large dimensions or otherwise abnormal.

To solve this I simply put my picture asset into a drawable subfolder instead of having it in the main drawable folder. E.g from res/drawable to res/drawable-mdpi worked for me. If you have a picture to use for everything not having a specific dpi, put it into res/drawable-nodpi. Here's a bit more about the dpi folders.