Tech Tip: Dropdown List Not Updating
PRODUCT: 4D | VERSION: 20 | PLATFORM: Mac & Win
Published On: November 6, 2025
It is a common issue among 4D developers to encounter dropdown list that fail to update in a form.
The developers will usually use a collection of commands from the hierarchical lists category, to create or load lists (New list, LOAD LIST), add new items (APPEND TO LIST or INSERT IN LIST), and finally save the list with the SAVE LIST command.
Lists are then attributed to form objects by defining the list as a data source. However, developer might not see the graphical object updating.
In that case, it is recommended to use the command OBJECT SET LIST BY REFERENCE. An example usage of this command with a dropdown list is presented in this documentation.
The developers will usually use a collection of commands from the hierarchical lists category, to create or load lists (New list, LOAD LIST), add new items (APPEND TO LIST or INSERT IN LIST), and finally save the list with the SAVE LIST command.
Lists are then attributed to form objects by defining the list as a data source. However, developer might not see the graphical object updating.
In that case, it is recommended to use the command OBJECT SET LIST BY REFERENCE. An example usage of this command with a dropdown list is presented in this documentation.