I have a data grid with items that have an attribute which contains a link to an external location.
On the data grid I have an action button to open a link. I select the attribute that contains the link. Now, whenever I execute this button (double-click, single click, select and click button) I get redirect to <currentlocation>/null.
I double checked, triple checked if the attribute has the correct value. In the end I had to use the URL redirector widget to make this work (using the same attribute: works like a charm).
I’ve stumbled on your question after encountering the same problem myself. After looking at a other (but related) forum post, I found the answer to our common problem: you need to have the attribute as a column in your datagrid for this to work. In my case, the client does not want to view the whole url in the datagrid so a solution for that would be to set the width of the url attribute column to 0.
I found the answer as a comment from Sufian Othman in this post: https://forum.mendix.com/link/questions/93151