Iterating through reacquired list of elements

Question

I have: two lists of unused and used elements. I have to transfer exact elements (element can be transferred on double click or click + button press than it disappears from 'unused elements' and appears in 'used elements') from first one to second. Discovered that first list is reacquired each time when I transfer element.

for x in range(0, len(offers)):
    try:
        if "21796" in offers[x].get_attribute('text'):
            ActionChains(app.driver).double_click(offers[x]).perform()
            offers = app.driver.find_elements_by_css_selector('select[name="unused_offers[]"]>option')
    except IndexError:
        break

So I run through the cycle in range of length of initial offers list and there are two problems:

1) If I won't reacquire 'offers' list I'll get StaleElementException

2) If I do I'll get out of initial offers list range because each iteration 'offers' list become shorter.

I decided to go through 2) way and just handle IndexError exception.

The question: Is there a better way to iterate through the list which becomes shorter then iteration range?

I did try also

ActionChains(app.driver).key_down(Keys.CONTROL, offers[x]).click(offers[x]).key_up(Keys.CONTROL, offers[x]).perform()

In cycle for escape list reacquire but there was the issue - cycle was just clicking elements one by one (looks like CTRL wasn't really held.

Answer 1

I would make an "endless" loop, find an offer on each iteration and exit the loop once an offer cannot be found (NoSuchElementException exception is raised). Implementation:

from selenium.common.exceptions import NoSuchElementException

while True:
    try:
        offer = app.driver.find_element_by_xpath('//select[@name="unused_offers[]"]/option[contains(@text, "21796")]')
    except NoSuchElementException:
        break

    ActionChains(app.driver).double_click(offer).perform()