Difficulty Dynamically Updating EnumProperty Items Stored in Addon Preferences

Hello dear Blender devs,
Summary: We are developing a Blender add-on that aims to create a dynamic combobox, allowing users to select items that can change based on user interactions or external data. These items are stored in the add-on preferences. However, I’m encountering challenges in dynamically updating the items displayed in the combobox.
The code below seems coherent but Pylance is uncapable of locating the register EnumNftsPropertyGroup

# Define a PropertyGroup to structure the data stored in AddonPreferences
class MyAddonPreferences(bpy.types.AddonPreferences):
    bl_idname = __name__

    # Define a CollectionProperty to store nfts for the combobox
    nfts_collection: bpy.props.CollectionProperty(
        items=[("default", "default", "Choose your nft")],
        name="My Nfts",
        description='All loaded Nfts by identifier',

# Define an Operator to update the nfts in the CollectionProperty
class UpdateNftsOperator(bpy.types.Operator):
    bl_idname = "my.update_nfts_operator"
    bl_label = "Update Nfts"

    def execute(self, context):
        # Dynamic logic to update items in the CollectionProperty
        addon_prefs = self.addon_prefs(context) # some operation occur here ...


# Define a PropertyGroup to represent items in the combobox
class EnumNftsPropertyGroup(bpy.types.PropertyGroup):
    identifier: bpy.props.StringProperty()
    name: bpy.props.StringProperty()
    url: bpy.props.StringProperty()

# Define a Panel to display the combobox
class MyPanel(bpy.types.Panel):
    bl_idname = "my.panel"
    bl_label = "My Panel"
    bl_category = "My Addon"
    bl_space_type = "VIEW_3D"
    bl_region_type = "UI"

    def draw(self, context):
        layout = self.layout

        # Access the items in AddonPreferences and populate the combobox
        preferences = context.preferences.addons[__name__].preferences
        nfts_collection = preferences.nfts_collection
        # Create a list of tuples for the items in the combobox
        nfts = [("default", "Default", "Choose your nft")]  # Default item

        # Add items based on your nfts_collection
        for nfts in nfts_collection:
            nfts.append((nfts.identifier, nfts.description, nfts.url))  # Use the data from your collection

        # Display the combobox
        layout.label(text="Select an item:")
        layout.prop(context.scene, "my_selected_item", text="NFT Items", icon='QUESTION')  # Use your scene property

def register():

def unregister():

The challenge I’m facing is how to effectively update the nfts_collection dynamically within the UpdateNftsOperator so that the combobox in the MyPanel accurately reflects the updated list of items. Maybe the registration of the EnumNftsPropertyGroup is not correct… but I can’t find out the reason.


  • Blender version: 3.6.3
  • Operating system: Linux ubuntu 22.04

Hopefully, this post receive positive feedback for us to progress on our adventure in Blender, I would greatly appreciate any assistance in resolving this issue. Thank you for your support!
Johnny Christmas aka jnxmas

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1 Like

thanks you for you reply, my mistake, I saw the categorie addon, but it must be for the official addon