operators.py

import bpy
from bpy.types import Operator


class InvokeMenuBaseClass:
    bl_options = {'INTERNAL'}

    @classmethod
    def poll(cls, context):
        # NOTE: This operator only exists to add a poll to the add modifier shortcut in the property editor.
        space = context.space_data
        return space and space.type == 'PROPERTIES' and space.context == cls.space_context

    def invoke(self, context, event):
        return bpy.ops.wm.call_menu(name=self.menu_id)


class INVOKE_OT_CLASSIC_MODIFIER_MENU(InvokeMenuBaseClass, Operator):
    bl_idname = "object.invoke_classic_modifier_menu"
    bl_label = "Add Modifier"
    bl_description = "Add a procedural operation/effect to the active object"
    menu_id = "OBJECT_MT_modifier_add"
    space_context = 'MODIFIER'


class INVOKE_OT_ASSET_MODIFIER_MENU(InvokeMenuBaseClass, Operator):
    bl_idname = "object.invoke_asset_modifier_menu"
    bl_label = "Add Asset Modifier"
    bl_description = "Add a modifier nodegroup to the active object"
    menu_id = "OBJECT_MT_modifier_add_assets"
    space_context = 'MODIFIER'


class INVOKE_OT_ADD_GPENCIL_SHADERFX_MENU(InvokeMenuBaseClass, Operator):
    bl_idname = "object.invoke_add_gpencil_shaderfx_menu"
    bl_label = "Add Grease Pencil Effect"
    bl_description = "Add a visual effect to the active grease pencil object"
    menu_id = "OBJECT_MT_gpencil_shaderfx_add"
    space_context = 'SHADERFX'


class INVOKE_OT_ADD_CONSTRAINTS_MENU(InvokeMenuBaseClass, Operator):
    bl_idname = "object.invoke_add_constraints_menu"
    bl_label = "Add Object Constraint"
    bl_description = "Add a constraint to the active object"
    menu_id = "OBJECT_MT_constraint_add"
    space_context = 'CONSTRAINT'


class INVOKE_OT_ADD_BONE_CONSTRAINTS_MENU(InvokeMenuBaseClass, Operator):
    bl_idname = "pose.invoke_add_constraints_menu"
    bl_label = "Add Bone Constraint"
    bl_description = "Add a constraint to the active bone"
    menu_id = "BONE_MT_constraint_add"
    space_context = 'BONE_CONSTRAINT'


if bpy.app.version >= (4, 3, 0):
    classes = (
        INVOKE_OT_CLASSIC_MODIFIER_MENU,
        INVOKE_OT_ASSET_MODIFIER_MENU,
        INVOKE_OT_ADD_GPENCIL_SHADERFX_MENU,
        INVOKE_OT_ADD_CONSTRAINTS_MENU,
        INVOKE_OT_ADD_BONE_CONSTRAINTS_MENU,
    )
else:
    class INVOKE_OT_ADD_GPENCIL_MODIFIER_MENU(InvokeMenuBaseClass, Operator):
        bl_idname = "object.invoke_add_gpencil_modifier_menu"
        bl_label = "Add Grease Pencil Modifier"
        bl_description = "Add a procedural operation/effect to the active grease pencil object"
        menu_id = "OBJECT_MT_gpencil_modifier_add"
        space_context = 'MODIFIER'

    classes = (
        INVOKE_OT_CLASSIC_MODIFIER_MENU,
        INVOKE_OT_ASSET_MODIFIER_MENU,
        INVOKE_OT_ADD_GPENCIL_MODIFIER_MENU,
        INVOKE_OT_ADD_GPENCIL_SHADERFX_MENU,
        INVOKE_OT_ADD_CONSTRAINTS_MENU,
        INVOKE_OT_ADD_BONE_CONSTRAINTS_MENU,
    )


def register():
    for cls in classes:
        bpy.utils.register_class(cls)


def unregister():
    for cls in classes:
        bpy.utils.unregister_class(cls)