enum_items not working with dynamic EnumProperty #86803

New Issue

Hugo Aboud · 2021-03-21T22:34:03+01:00

Hugo Aboud commented

2021-03-21 22:34:03 +01:00

System Information
Operating system: Windows 10

Blender Version
Broken: 2.91.2, 5be9ef4177, master, 2021-01-19

Short description of error

When using a callback to populate a (dynamic) EnumProperty, the enum_items property available for that rna_type returns an empty collection.

Exact steps for others to reproduce the error

Minimal script sample:

import bpy

class DMX_OT_Test(bpy.types.Operator):
    bl_label = "DMX > Test"
    bl_idname = "dmx.test"

    entries: bpy.props.EnumProperty(
        name = "Entries",
        description = "Entries to be loaded into enum_items",
        items = (('id0','',''),('id1','',''),('id2','',''))
    )
    
    dyn_entry_items = []
    def entryListItems(self, context):
        if (not len(DMX_OT_Test.dyn_entry_items)):
            DMX_OT_Test.dyn_entry_items = (('dyn_id0','',''),('dyn_id1','',''),('dyn_id2','',''))
        return DMX_OT_Test.dyn_entry_items
    
    dyn_entries: bpy.props.EnumProperty(
        name = "Dynamic Entries",
        description = "Dynamic entries to be loaded into enum_items",
        items = entryListItems
    )

    def execute(self, context):
        print('---\n')
        
        print(self.rna_type)
        print(self.rna_type.properties)
        for prop in self.rna_type.properties:
            print("\t",prop)
            
        print("\nself.entries:", self.entries)
        print(self.rna_type.properties['entries'].enum_items)
        for item in self.rna_type.properties['entries'].enum_items:
            print("\t",item)

        print("\nself.dyn_entries:", self.dyn_entries)
        print(self.rna_type.properties['dyn_entries'].enum_items)
        for item in self.rna_type.properties['dyn_entries'].enum_items:
            print("\t",item)
            print("\t",item.identifier)
        return {'FINISHED'}
    
def register():
    bpy.utils.register_class(DMX_OT_Test)


def unregister():
    bpy.utils.unregister_class(DMX_OT_Test)

if __name__ == "__main__":
    
    register()

# test call
bpy.ops.dmx.test()
unregister()

Output:

<bpy_struct, Struct("DMX_OT_test")>
<bpy_collection[3], Struct.properties>
  <bpy_struct, PointerProperty("rna_type")>
  <bpy_struct, EnumProperty("entries")>
  <bpy_struct, EnumProperty("dyn_entries")>

self.entries: id0
<bpy_collection[3], EnumProperty.enum_items>
  <bpy_struct, EnumPropertyItem("id0")>
  <bpy_struct, EnumPropertyItem("id1")>
  <bpy_struct, EnumPropertyItem("id2")>

self.dyn_entries: dyn_id0
  <bpy_collection[0], EnumProperty.enum_items>

**System Information** Operating system: Windows 10 **Blender Version** Broken: 2.91.2, 5be9ef417703, master, 2021-01-19 **Short description of error** When using a callback to populate a (dynamic) `EnumProperty`, the `enum_items` property available for that `rna_type` returns an empty collection. **Exact steps for others to reproduce the error** Minimal script sample: ``` import bpy class DMX_OT_Test(bpy.types.Operator): bl_label = "DMX > Test" bl_idname = "dmx.test" entries: bpy.props.EnumProperty( name = "Entries", description = "Entries to be loaded into enum_items", items = (('id0','',''),('id1','',''),('id2','','')) ) dyn_entry_items = [] def entryListItems(self, context): if (not len(DMX_OT_Test.dyn_entry_items)): DMX_OT_Test.dyn_entry_items = (('dyn_id0','',''),('dyn_id1','',''),('dyn_id2','','')) return DMX_OT_Test.dyn_entry_items dyn_entries: bpy.props.EnumProperty( name = "Dynamic Entries", description = "Dynamic entries to be loaded into enum_items", items = entryListItems ) def execute(self, context): print('---\n') print(self.rna_type) print(self.rna_type.properties) for prop in self.rna_type.properties: print("\t",prop) print("\nself.entries:", self.entries) print(self.rna_type.properties['entries'].enum_items) for item in self.rna_type.properties['entries'].enum_items: print("\t",item) print("\nself.dyn_entries:", self.dyn_entries) print(self.rna_type.properties['dyn_entries'].enum_items) for item in self.rna_type.properties['dyn_entries'].enum_items: print("\t",item) print("\t",item.identifier) return {'FINISHED'} def register(): bpy.utils.register_class(DMX_OT_Test) def unregister(): bpy.utils.unregister_class(DMX_OT_Test) if __name__ == "__main__": register() # test call bpy.ops.dmx.test() unregister() ``` Output: ``` <bpy_struct, Struct("DMX_OT_test")> <bpy_collection[3], Struct.properties> <bpy_struct, PointerProperty("rna_type")> <bpy_struct, EnumProperty("entries")> <bpy_struct, EnumProperty("dyn_entries")> self.entries: id0 <bpy_collection[3], EnumProperty.enum_items> <bpy_struct, EnumPropertyItem("id0")> <bpy_struct, EnumPropertyItem("id1")> <bpy_struct, EnumPropertyItem("id2")> self.dyn_entries: dyn_id0 <bpy_collection[0], EnumProperty.enum_items> ```

Hugo Aboud commented

2021-03-21 22:34:03 +01:00

Added subscriber: @Hugo-Aboud

Jaume Bellet commented

2021-03-22 09:32:20 +01:00

Added subscriber: @JaumeBellet

Jaume Bellet commented

2021-03-22 09:32:20 +01:00

Issue here is that RNA_property_enum_items_ex function is called with NULL as context.

When calling the callback (to get the value for example), is scaled up from a BPY_context_get() call on bpy_rna.c

Issue here is that RNA_property_enum_items_ex function is called with NULL as context. When calling the callback (to get the value for example), is scaled up from a BPY_context_get() call on bpy_rna.c

Philipp Oeser commented

2021-03-22 15:08:23 +01:00

Added subscriber: @lichtwerk

Philipp Oeser commented

2021-03-22 15:08:23 +01:00

Changed status from 'Needs Triage' to: 'Needs User Info'

Philipp Oeser commented

2021-03-22 15:08:23 +01:00

I can confirm the behavior.

Trying to understand the usecase a bit better though (since these are 'expanded' correctly for the UI and elsewhere):
Why do you need access to these like demonstrated above?
While not as convenient as from 'proper expanded' collection of EnumPropertyItem, you could get them directly through the callback, no?

See
#86803.blend

I can confirm the behavior. Trying to understand the usecase a bit better though (since these are 'expanded' correctly for the UI and elsewhere): Why do you need access to these like demonstrated above? While not as convenient as from 'proper expanded' collection of `EnumPropertyItem`, you could get them directly through the callback, no? See [#86803.blend](https://archive.blender.org/developer/F9904044/T86803.blend)

Hugo Aboud commented

2021-03-22 17:31:00 +01:00

The issue came up while I was trying to setup dynamic nested Menus using context_pointer_set, as described here.

Since the data argument must be of AnyType I need acess to the EnumPropertyItem references.

The solution for now has been populating the enum items when the annotations are evaluated. However, this can only be done once, not allowing for dynamic content changes.

manufacturers: EnumProperty(
    name = "Manufacturers",
    description = "Fixture GDTF Manufacturers",
    items = DMX_GDTF.getManufacturerList()
)

The issue came up while I was trying to setup dynamic nested Menus using `context_pointer_set`, as described [here](https://blender.stackexchange.com/a/45855/107464). Since the `data` argument must be of `AnyType` I need acess to the `EnumPropertyItem` references. The solution for now has been populating the enum items when the annotations are evaluated. However, this can only be done once, not allowing for dynamic content changes. ``` manufacturers: EnumProperty( name = "Manufacturers", description = "Fixture GDTF Manufacturers", items = DMX_GDTF.getManufacturerList() ) ```

Ankit Meel commented

2021-03-30 16:11:12 +02:00

Changed status from 'Needs User Info' to: 'Needs Triage'

Philipp Oeser commented

2021-04-06 13:42:45 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Philipp Oeser commented

2021-04-06 13:42:45 +02:00

Interesting usecase, confirming then.

Campbell Barton commented

2021-04-28 16:42:03 +02:00

Added subscriber: @ideasman42

Campbell Barton commented

2021-04-28 16:42:03 +02:00

Currently enum_items only works for static items. - That is a fixed array of items.

For C/C++ code both can be set, for Python passing the item as a function makes it impossible

Marking as a TODO since this isn't an error in the code.

Currently `enum_items` only works for static items. - That is a fixed array of items. For C/C++ code both can be set, for Python passing the item as a function makes it impossible Marking as a TODO since this isn't an error in the code.

Philipp Oeser removed the

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enum_items not working with dynamic EnumProperty #86803