We would like to have a repeating data list of categories and within that another repeating data list of transactions corresponding to the categories. Is this possible? If so, how can we set it up?

We understand how to make the first repeating data list of categories by simply adding a container to it. However, as the designs show, we would like to have a second repeating data list of information relating to that category that is only displayed once the category repeating data list item is clicked by the user which would open the second repeating data list. How should we go about setting this up especially if we want this to be the case for other category items when generated? 

We were thinking that we would have to use conditional visibility for the second relating data list which is triggered by the clicking of the first category repeating data list item.

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