What I need to do is quite simple although is causing me lots of trouble.
I need to create programmatically an AssetUrlSelector in a web part that selects a file in sharepoint 2010 and makes its path available to be used elsewhere.
So far I have managed to create the AssetUrlSelector and display the path on a textbox, however I cannot use this as every reference to it will be null.
Have you got any practical example?
Try the Document ID Service. In short this service generates IDs for documents (files) and generates an url with this ID so even if the file is moved the url stays valid and the service returns the document. This service might rely on search functionality unless you implement your custom search. Here is an article on how to configure OOB Doc IDs here. Also you can google further if you’re interested.