Detect a Blender Keyboard Shortcut

Question

How would I detect a Blender keyboard shortcut in edit mode? I'm trying to detect the merge operation (Alt+M), but I don't want to change the shortcut of anything, just execute a function at the same time that the operation is called by the key combination. I thought about the draw function which constantly listens, but that doesn't seem ideal.

Answer 1

Found it through the modal operator. There were other posts touching on this, but basically it will keep Blender's keymaps but still execute your custom code.

import bpy

class ModalOperator(bpy.types.Operator):
    bl_idname = "object.modal_operator"
    bl_label = "Simple Modal Operator"

    def execute(self, context):
        print("This is the modal operator")
        return {'FINISHED'}

    def modal(self, context, event):
        if event.type == 'ESC':  # Confirm
            print("This is finished")
            return {'FINISHED'}
        elif event.alt:
            if event.type == 'M':  # Confirm
                print("This is a Blender Shortcut key")
            return {'PASS_THROUGH'}

        return {'PASS_THROUGH'}

    def invoke(self, context, event):
        print("This is the invoker")

        context.window_manager.modal_handler_add(self)
        return {'RUNNING_MODAL'}

bpy.utils.register_class(ModalOperator)

bpy.ops.object.modal_operator('INVOKE_DEFAULT')