Handle infinite scroll

Infinite-scroll feeds load more content as the user nears the bottom of the page. The test pattern is simple: scroll, wait for the item count to grow, repeat — but never use a fixed number of iterations or sleeps.

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Scroll until the target item appears

The safest stop condition is finding the element you actually care about:

ProductListPage.java

import io.testfly.test.BasePage;
import io.testfly.wait.WaitEngine;
import org.openqa.selenium.By;

public class ProductListPage extends BasePage {

    private static final By PRODUCTS = By.cssSelector(".product-card");

    public void scrollUntilProductVisible(String productId) {
        By target = By.cssSelector("[data-product-id='" + productId + "']");

        for (int i = 0; i < 50; i++) {   // generous upper bound, not a fixed expectation
            if (find(target).count() > 0) {
                return;                  // found it
            }
            int before = find(PRODUCTS).count();
            scrollToBottom();
            WaitEngine.wait(d -> !d.findElements(target).isEmpty()
                || d.findElements(PRODUCTS).size() > before
                || !d.findElements(By.cssSelector(".catalog-end")).isEmpty());
            if (find(target).count() == 0 && find(".catalog-end").count() > 0) {
                throw new AssertionError("Catalog ended before product: " + productId);
            }
        }
        throw new AssertionError("Product not loaded after scrolling: " + productId);
    }
}

ProductTest.java

import io.testfly.test.BaseTest;
import org.testng.annotations.Test;

public class ProductTest extends BaseTest {

    @Test
    public void oldProductLoadsOnScroll() {
        open("/products");
        ProductListPage list = new ProductListPage();
        list.scrollUntilProductVisible("PROD-1985");
        assertThat(find("[data-product-id='PROD-1985']")).isVisible();
    }
}

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Load the catalog until its end marker

Use this when you want to load the entire catalog before making assertions:

// Inside ProductListPage (scrollToBottom() is a protected BasePage helper)
public int loadAllProducts() {
    By products = By.cssSelector(".product-card");
    By end = By.cssSelector(".catalog-end");
    for (int page = 0; page < 100; page++) {
        if (find(end).count() > 0) {
            return find(products).count();
        }
        int before = find(products).count();
        scrollToBottom();
        WaitEngine.wait(d -> d.findElements(products).size() > before
            || !d.findElements(end).isEmpty());
    }
    throw new AssertionError("Catalog did not reach its end within 100 scrolls");
}

Use an application-specific end marker such as .catalog-end. An unchanged count or document.readyState does not prove that asynchronous loading has finished. The iteration bound prevents an endless feed from hanging the test.

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Avoid the common pitfalls

❌ Don't	✅ Do
Thread.sleep(2000) after each scroll	Wait for a real condition: new items, a sentinel element, or no growth
Scroll a fixed 10 times	Scroll until the target appears or growth stops
Assert immediately after scrollToBottom()	Wait for the DOM to update first
Use absolute pixel scrolls	Scroll to the bottom of document.body so it works at any viewport

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When the scroll trigger is a button

Some feeds use a "Load more" button instead of automatic scroll:

// Inside ProductListPage; imports WaitEngine and ExpectedConditions
while (find("#load-more").isVisible()) {
    int before = find(".product-card").count();
    find("#load-more").click();
    WaitEngine.wait(ExpectedConditions.numberOfElementsToBeMoreThan(
        By.cssSelector(".product-card"), before));
}

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Deeper reference: WaitEngine — WaitEngine.wait(ExpectedCondition) for custom conditions, waitForPageLoad(), and other wait patterns.