How to make a conditional dropdown from another dropdown selection

I am using a template grid to display assets for design threads based on an industry. Meaning you will select an industry which will show design threads for that industry and once you have selected the design thread all of the available assets will appear in the grid. I have an entity that is connected to the template grid which are the assets entity and have two drop down selectors one for the industry and another for the threads. Both of these are lists of the respective industries and threads with their own entities that have associations with the assets entity. I am wondering how can I use the selection of the industries to only show threads associated with that industry and then only show the assets to that thread. 
1 answers

You are looking for the constrained by function. See the documentation here:

It is in the 2.9.2 section.