How to create a drop down list containing many materials and assign to the box. Please help me!

[seltzdesign (Armin Seltz)]

Check this thread and the solution by @AndersDeleuran. It can “automatically” update the keys and values of a dropdown.

Setting the entries in a value list?

It’s only a bug if there are software requirements. Anywho, you can add this line to prevent the code running before it has something to work with (i.e. attempting to populate with nothing): [2021-01-08 16_07_16-Grasshopper - 210108_PopulateValueList_01_] 210108_PopulateValueList_01.gh (4.2 KB) And these bits to avoid the item selection error raised when populating an empty value list: [2021-01-08 16_33_02-Grasshopper - 210108_PopulateValueList_01] 210108_PopulateValueList_02.gh (4.4 KB) …