If condition to show list based upon another cell value

Hello everyone. I am trying to add a list to a cell using data validation. What I am trying to accomplish is basically: if cell A1 equals 1 then show list, otherwise show blank (or no list will be shown), however I cannot get it to work that simply. What I have tried is adding a data validation using custom and then including the following formula: =IF($A$1="1",List,""), however this does not work. If this is possible, could someone please help me with the proper method of doing this?