Time delay when selecting objects in a python script!

Question

I am trying to create a simple script in python that will allow me to select objects from my scene. What I did, is created a scene, and added 3 objects, a cube, a sphere and a cylinder, and they are named; Cube, Sphere and a Cylinder , respectively. I am trying to create a python script in which I want to select these objects within a time delay. So for example I want to select the Cylinder, then 1 second later I want to select the Cube and then 1 second after that I want to select the Sphere. At the end of my script all 3 objects should be selected. In my script they are all getting selected but they all get selected instantaneously at the end of the program. I used the time module for python to create the time delay of 1 second after I select one object, but it doesn't seem like the time delay does anything, because all 3 objects gets selected simultaneously. Here is my python script and blender project.

Firstly, I create an empty list, which i then fill up with the name of all the objects in my scene, in my case its only 3 objects. I then loop through those objects from my list / scene and select them 1 by 1 with a 1 second delay in between. However when the script ends all the objects are selected instantly. And yes, I did unselect everything before running the script.

Does anyone know how I can fix or re write my code, so when I run the script, it will select an object then wait for 1 second and select the other object and then wait 1 more second after that and select the last object.

Of course, I only used only 3 objects in my scene for simplicity reasons, but this script should of course work for any scene and any number of objects.

Answer 1

Modal timer operator

Would suggest not using time.sleep and use a modal timer operator instead.' Example using modal timer operator template.

import bpy

class ModalTimerOperator(bpy.types.Operator):
    """Operator which runs its self from a timer"""
    bl_idname = "wm.modal_timer_operator"
    bl_label = "Modal Timer Operator"

    _timer = None
    ob_index = 0

    def modal(self, context, event):
        scene = context.scene
        if self.ob_index >= len(scene.objects):
            self.cancel(context)
            return {'CANCELLED'}

        if event.type == 'TIMER':
            scene.objects[self.ob_index].select = True
            self.ob_index += 1

        return {'PASS_THROUGH'}

    def execute(self, context):
        wm = context.window_manager
        self._timer = wm.event_timer_add(1, context.window)
        wm.modal_handler_add(self)
        return {'RUNNING_MODAL'}

    def cancel(self, context):
        wm = context.window_manager
        wm.event_timer_remove(self._timer)

def register():
    bpy.utils.register_class(ModalTimerOperator)

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

if __name__ == "__main__":
    register()

    # test call
    bpy.ops.wm.modal_timer_operator()

Answer 2

It ought to function as intended. Try printing time between iterations.