Perhaps this is better logic:
Two lists your spinner items and your images, these should correlate with each other, e.g. SpinnerList index 2 relates to imageList index 2.
Then after making the selection from the spinner, the corresponding image is shown.
This is a demo example, and takes no account of the location of the image files. You will need to provide the correct path to the files, once you have returned the filename. The above should work if your images are in your assets/media folder.