Delayed Work using Clock

Summary

• author: Mathieu Virbel
• kivy: >= 1.0.6

The idea is to unroll a working loop to not block the UI. Let's imagine that you want to create thousand of images. If you are doing it in a loop, the UI will stuck until all the images are loaded and added.

You can create one image per frame for example, then the UI will be not stuck at all.

Usage

from kivy.clock import Clock

def delayed_work(func, items, delay=0):
    '''Apply the func() on each item contained in items
    '''
    if not items:
        return
    def _delayed_work(*l):
        item = items.pop()
        if func(item) is False or not len(items):
            return False
        Clock.schedule_once(_delayed_work, delay)
    Clock.schedule_once(_delayed_work, delay)

Usage example

def create_image(filename):
  image = Image(source=filename)
  my_container.add_widget(image)

items = ['img1.png', 'img2.png', 'toto.png', 'azdmlk.png']
delayed_work(create_image, items)