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Create Pick List from custom field in Sales Order form

Hello Right now when you click on Create -> Pick List, it will choose the items from the “Items” table. Makes sense, but we have a requirement to get the pick list from a custom table that’s added in the form. Is there a way to create a pick list from this source of data in the form?

You can remove the default option and add your own using Custom Scripting:

https://docs.erpnext.com/docs/user/manual/en/customize-erpnext/custom-scripts/rename-buttons-in-form-view

You will have to point the button to a valid method in the system, or create your own which will do the job. The documentation covers some basic aspects about this.