Window handles in Selenium Python - Build an Automation Script

Verify switching between multiple browser windows

Preconditions (2)

Step 1: Open the main test page at 'https://example.com/main'

Step 2: Click the link with id 'open-new-window' that opens a new browser window

Step 3: Switch to the new window

Step 4: Verify the new window's title is 'New Window'

Step 5: Close the new window

Step 6: Switch back to the original window

Step 7: Verify the original window's title is 'Main Page'

✅ Expected Result: The test switches to the new window correctly, verifies its title, closes it, switches back to the original window, and verifies the original title.

Automation Requirements - Selenium with Python

Assertions Needed:

Verify new window title is 'New Window'

Verify original window title is 'Main Page'

Best Practices:

Use explicit waits where needed

Use window handles to switch windows

Close only the new window before switching back

Use try-finally or context management to ensure windows are closed

Automated Solution

Selenium Python

from selenium import webdriver
from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

# Initialize the Chrome driver
with webdriver.Chrome() as driver:
    wait = WebDriverWait(driver, 10)
    # Open the main page
    driver.get('https://example.com/main')
    original_window = driver.current_window_handle

    # Click the link that opens a new window
    wait.until(EC.element_to_be_clickable((By.ID, 'open-new-window'))).click()

    # Wait for the new window
    wait.until(EC.number_of_windows_to_be(2))

    # Get all window handles
    windows = driver.window_handles

    # Switch to the new window
    for window in windows:
        if window != original_window:
            driver.switch_to.window(window)
            break

    # Verify the new window title
    wait.until(EC.title_is('New Window'))
    assert driver.title == 'New Window', f"Expected title 'New Window' but got '{driver.title}'"

    # Close the new window
    driver.close()

    # Switch back to original window
    driver.switch_to.window(original_window)

    # Verify the original window title
    wait.until(EC.title_is('Main Page'))
    assert driver.title == 'Main Page', f"Expected title 'Main Page' but got '{driver.title}'"

This script uses Selenium WebDriver with Python to automate the test case.

First, it opens the main page and stores the original window handle.

Then it clicks the link that opens a new window and waits until two windows are open.

It switches to the new window by comparing window handles.

It waits for the new window's title to be 'New Window' and asserts it.

Next, it closes the new window and switches back to the original window.

Finally, it waits for the original window's title to be 'Main Page' and asserts it.

Using explicit waits ensures the script waits for elements and conditions properly.

Using a context manager for the driver ensures the browser closes after the test.

Common Mistakes - 3 Pitfalls

Not waiting for the new window to open before switching

Closing the original window instead of the new window

Using hardcoded window handles

Bonus Challenge

Now add data-driven testing with 3 different links that open different new windows and verify their titles.

Show Hint