How to add a picture in costume fields

Hi,
I have a store that sells various materials, they have height, width and texture.

I did variations of height and width but 160 came on the product, according to this price is determined.

Now I need to add texture that does not cost anything but a picture need to appear when you select a texture.

Any ideas how to do?

Many thank's.

To be more explicit it is the link:
www.sunshadow.eu/produse/basic-shop/prod...ine-retractabile-sun

And I create custom field "tesatura" had to allocate according to the vaule the picture

You will have to edit the file show_block_custom_item via the menu Display->Views and add some javascript code in the "onchange" attribute of the custom field in order to display the image you want when the selection changes.

Ty,
But i'm not very good at js u can give me 1 example ?

Basically, you need to display the div where you have the image for the current selection and hide the others.
to display the div of the current selection, you can do like that:

onchange="document.getElementById('div_'+this.value).display='block';"

So if the image is in a HTML div with the id div_myimage and the value of the selection should be myimage with that example. You will also need additional code to hide the other div like that:
document.getElementById(other_div_id).display='none';

Hi Nicolas,
Thank you for prompt support, I managed to solve the problem with your support
hika shop is actually really good and with some adaptations for our specific I think we will do a really good work...

We haven't finished yet if we have more problems we will bother you with some questions that we will have

All the best.