You have the ability to add a custom field for your custom module of type Media (images, videos, files).
Then choose what kind of media this field will manage and save the changes. If you have a pop up which asks you
Are you sure you want to save the changes to this content type?
Check Update widget templates as well
and click Yes, save the changes.
After that when you create an item of the module you will have an image selector:
This is how you should associate an item with an image.
After the item is created and the widget is dropped on the page, you could see the item and the image in the details view of the item. The field is added automatically to the details template.
If you want to add it to the list template you need to go to the properties of the widget, navigate to List settings, choose the template and add the AssetsField there (copy it from the details template).
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
system and vote to affect the priority of the items