How to make Selenium wait until an element is present?

Question

I'm trying to make Selenium wait for an element that is dynamically added to the DOM after page load. I tried this:

fluentWait.until(ExpectedConditions.presenceOfElement(By.id("elementId"));

In case it helps, here is fluentWait:

FluentWait fluentWait = new FluentWait<>(webDriver) {
    .withTimeout(30, TimeUnit.SECONDS)
    .pollingEvery(200, TimeUnit.MILLISECONDS);
}

But it throws a NoSuchElementException. It looks like presenceOfElement expects the element to be there, so this is flawed. This must be bread and butter to Selenium, and I don't want to reinvent the wheel... Is there an alternative, ideally without rolling my own Predicate?

Answer 1

You need to call ignoring with an exception to ignore while the WebDriver will wait.

FluentWait<WebDriver> fluentWait = new FluentWait<>(driver)
        .withTimeout(30, TimeUnit.SECONDS)
        .pollingEvery(200, TimeUnit.MILLISECONDS)
        .ignoring(NoSuchElementException.class);

See the documentation of FluentWait for more information. But beware that this condition is already implemented in ExpectedConditions, so you should use:

WebElement element = (new WebDriverWait(driver, 10))
   .until(ExpectedConditions.elementToBeClickable(By.id("someid")));

*Fewer versions of Selenium:

withTimeout(long, TimeUnit) has become withTimeout(Duration)
pollingEvery(long, TimeUnit) has become pollingEvery(Duration)

So the code will look as such:

FluentWait<WebDriver> fluentWait = new FluentWait<>(driver)
        .withTimeout(Duration.ofSeconds(30)
        .pollingEvery(Duration.ofMillis(200)
        .ignoring(NoSuchElementException.class);

A basic tutorial for waiting can be found here.