A loader appears after clicking a button then content loads. How do you handle it in Selenium?

Answer

Handling Loader → Content Pattern in Selenium

This is a very common pattern: click action → spinner appears → content loads. You must wait for the spinner to disappear before interacting with the loaded content.

Standard Pattern

Java

// Step 1: Click the action button
driver.findElement(By.id("loadDataBtn")).click();

WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(20));

// Step 2: Wait for loader/spinner to DISAPPEAR
wait.until(
    ExpectedConditions.invisibilityOfElementLocated(By.cssSelector(".spinner"))
);

// Step 3: Wait for content to APPEAR
WebElement content = wait.until(
    ExpectedConditions.visibilityOfElementLocated(By.cssSelector(".data-container"))
);

// Step 4: Interact with loaded content
System.out.println("Content loaded: " + content.getText());

If Loader Is Not in DOM Initially

Java

// Click
driver.findElement(By.id("loadBtn")).click();

// Wait for loader to APPEAR first (confirms action triggered)
wait.until(
    ExpectedConditions.visibilityOfElementLocated(By.cssSelector(".loading-overlay"))
);

// Then wait for it to DISAPPEAR
wait.until(
    ExpectedConditions.invisibilityOfElementLocated(By.cssSelector(".loading-overlay"))
);

// Now content is ready

Reusable Method

Java

public void waitForLoaderAndContent(String loaderCss, String contentCss) {
    WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(30));

    // Wait for loader to go away
    wait.until(ExpectedConditions.invisibilityOfElementLocated(
        By.cssSelector(loaderCss)
    ));

    // Wait for content
    wait.until(ExpectedConditions.visibilityOfElementLocated(
        By.cssSelector(contentCss)
    ));
}

// Usage
clickLoadButton();
waitForLoaderAndContent(".spinner", ".results-grid");

Handle Slow Networks in CI

Java

// Increase timeout for CI environments
int timeout = System.getenv("CI") != null ? 45 : 15;
WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(timeout));

When Timeout Happens

If the wait times out, it is a real defect — the spinner never disappeared or content never loaded within the acceptable time. Log it, take a screenshot, and report it as a bug rather than increasing the timeout further.