"NoSuchWindowException: no such window: window was already closed" while switching tabs using Selenium and WebDriver through Python3

Question

I have a form that opens in a new tab when I click on it. When I try to navigate to that new tab, I keep getting a NoSuchWindowException. Code is pretty straightforward. 'myframe' is the frame within the new tab that the information will eventually get plugged into. Should I be waiting for something else?

from selenium import webdriver
from selenium.webdriver.support import expected_conditions as EC
from selenium.webdriver.support.ui import WebDriverWait, Select
from selenium.webdriver.common.by import By
from selenium.common.exceptions import TimeoutException, NoSuchElementException
import time
import pandas as pd

url = *****
driver = webdriver.Chrome(executable_path = r'S:\Engineering\Jake\MasterControl Completing Pipette CalPM Forms\chromedriver')
driver.get(url)

wait = WebDriverWait(driver, 5)    

window_before = driver.window_handles[0]
driver.find_element_by_id('portal.scheduling.prepopulate').click()
window_after = driver.window_handles[1]
driver.switch_to_window(window_after)
driver.switch_to_default_content()
wait.until(EC.frame_to_be_available_and_switch_to_it('myframe'))

---

Traceback (most recent call last):

  File "<ipython-input-308-2aa72eeedd51>", line 1, in <module>
    runfile('S:/Engineering/Jake/MasterControl Completing Pipette CalPM Forms/Pipette Completing CalPM Tasks.py', wdir='S:/Engineering/Jake/MasterControl Completing Pipette CalPM Forms')

  File "C:\ProgramData\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 678, in runfile
    execfile(filename, namespace)

  File "C:\ProgramData\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 106, in execfile
    exec(compile(f.read(), filename, 'exec'), namespace)

  File "S:/Engineering/Jake/MasterControl Completing Pipette CalPM Forms/Pipette Completing CalPM Tasks.py", line 150, in <module>
    create_new_cal_task(asset_number)

  File "S:/Engineering/Jake/MasterControl Completing Pipette CalPM Forms/Pipette Completing CalPM Tasks.py", line 130, in create_new_cal_task
    driver.switch_to_default_content()

  File "C:\ProgramData\Anaconda3\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 783, in switch_to_default_content
    self._switch_to.default_content()

  File "C:\ProgramData\Anaconda3\lib\site-packages\selenium\webdriver\remote\switch_to.py", line 65, in default_content
    self._driver.execute(Command.SWITCH_TO_FRAME, {'id': None})

  File "C:\ProgramData\Anaconda3\lib\site-packages\selenium\webdriver\remote\webdriver.py", line 314, in execute
    self.error_handler.check_response(response)

  File "C:\ProgramData\Anaconda3\lib\site-packages\selenium\webdriver\remote\errorhandler.py", line 242, in check_response
    raise exception_class(message, screen, stacktrace)

NoSuchWindowException: no such window: window was already closed
  (Session info: chrome=68.0.3440.106)
  (Driver info: chromedriver=2.40.565498 (ea082db3280dd6843ebfb08a625e3eb905c4f5ab),platform=Windows NT 6.1.7601 SP1 x86_64)

Answer 1

I was able to fix this by using

While True:
    try:
        [navigate to the new frame, wait for a specific element to show up]
        break
    except (NoSuchWindowException, NoSuchElementException):
        pass

I had not realized that when I clicked to open the form, another window opened briefly in the background, then closed. This increased the window_handles to 2, so doing anything relating to waiting for 2 window handles still kept throwing an error.