Different Appium Scroll Strategies

Appium, being an open-source tool, allows developers to automate mobile applications easily. It is widely used for testing on both Android and iOS platforms. A fundamental aspect of mobile testing is scrolling and Appium offers various strategies to perform this task efficiently. Understanding these different scroll strategies is crucial for adjusting your testing approach to the specific requirements of your mobile application.

Different Appium Scroll Strategies

Appium facilitates scrolling by offering various strategies, that testers can leverage based on the application’s structure and the desired outcome. Let’s delve into the different Appium scroll strategies available.

1. Scroll by Coordinates

The simplest way to scroll in Appium is by using coordinates. This involves defining a starting point and an endpoint for the scroll action. However, this method is somewhat static and may not be suitable for dynamic content or varying screen sizes.

Implementation Example:

Java

// Scroll from point (x1, y1) to (x2, y2)
driver.scroll(100, 500, 100, 100)

This example scrolls from coordinates (100, 500) to (100, 100).

2. UiScrollable (Android)

The UiScrollable class in Appium is used for handling scrolling actions in Android applications during automated testing. It provides a way to perform dynamic and complex scrolling operations by allowing testers to specify scrollable elements and scroll directions.

Example:

Java

public static void scrollDownUsingUiScrollable(AndroidDriver<AndroidElement> driver) {
    // Find a scrollable element using UiSelector
    MobileElement scrollableElement = driver.findElementByAndroidUIAutomator(
            "new UiScrollable(new UiSelector().scrollable(true)).scrollIntoView("
                    + "new UiSelector().text(\"ElementTextToScrollTo\"))");

    // Perform the scrolling action
    scrollableElement.sendKeys("");
}

1. driver.findElementByAndroidUIAutomator(…):
   • This line uses the findElementByAndroidUIAutomator method provided by the Appium AndroidDriver to locate a UI element using the Android UI Automator framework.
   • The argument passed to findElementByAndroidUIAutomator is a string representing an Android UI Automator script.
2. new UiScrollable(new UiSelector().scrollable(true)): This creates a UiScrollable instance, specifying that the element should be scrollable. This part identifies the scrollable container.
3. .scrollIntoView(new UiSelector().text(“ElementTextToScrollTo”)): This further refines the selection by specifying that the scrolling action should bring into view an element with the text “ElementTextToScrollTo.”
4. MobileElement scrollableElement = … :
   • The result of the findElementByAndroidUIAutomator method is assigned to the scrollableElement variable, which is of type MobileElement.
   • scrollableElement now represents the identified scrollable element based on the provided Android UI Automator script.
5. scrollableElement.sendKeys(“”):
   • This line is a workaround commonly used for triggering scroll actions in Appium.
   • By calling sendKeys(“”) on the scrollableElement, the script simulates sending an empty string as input, which in turn is often interpreted as a keypress, triggering the scroll action within the identified scrollable element.

3. Mobile JSON Wire Protocol Actions

The Mobile JSON Wire Protocol is a communication protocol used by Appium to interact with mobile devices. It defines a set of actions or commands that Appium sends to the device under test and the device responds accordingly. One of these actions is mobile:scroll, which allows for scrolling within the current view on both Android and iOS platforms.

Example:

Java

public static void scrollDownUsingMobileScroll(AppiumDriver<MobileElement> driver) {
    // Execute the mobile:scroll action to scroll down
    driver.executeScript("mobile:scroll", ImmutableMap.of("direction", "down"));
}

The purpose of this method is to simulate a scroll-down action in the current view of the mobile application.

Let’s break down the method scrollDownUsingMobileScroll step by step:

1. driver.executeScript(“mobile:scroll”, ImmutableMap.of(“direction”, “down”)):
   • The driver.executeScript method in Appium allows you to execute arbitrary JavaScript or the mobile JSON Wire Protocol commands on the device under test.
2. “mobile:scroll”: This is the script or command that is being executed. In this case, it’s the mobile:scroll action.
3. ImmutableMap.of(“direction”, “down”):
   • This part provides parameters to the mobile:scroll action. In this example, it specifies that the scrolling direction should be “down.”
   • ImmutableMap.of is a way to create an immutable map (key-value pairs) in Java. The “direction” is the key, and “down” is the value.

4. Touch Actions (Multi-Touch Scroll)

The Touch Actions in Appium allow testers to simulate multi-touch gestures, providing a way to interact with the application through complex touch-based scenarios. In the context of scrolling, Touch Actions can be used to simulate scrolling actions when native scrolling might not be applicable or when a more customized interaction is required.

Example:

Java

public static void performScrollWithTouchActions(AndroidDriver<MobileElement> driver) {
    // Create a TouchAction instance
    TouchAction touchAction = new TouchAction(driver);

    // Perform a scroll by initiating a press at (100, 500), moving to (100, 100), and releasing
    touchAction.press(PointOption.point(100, 500))
               .moveTo(PointOption.point(100, 100))
               .release()
               .perform();
}

Explanation:

1. Create a TouchAction Instance: TouchAction touchAction = new TouchAction(driver); This line creates a new instance of the TouchAction class, which is provided by the Appium Java client library. This instance will be used to define a sequence of touch-based actions.
2. Define Touch Actions Sequence:
   • The press method initiates a touch at the specified coordinates (100, 500).
   • The moveTo method simulates moving the touch to the specified coordinates (100, 100).
   • The release method signals the release of the touch, completing the scroll action.
   • The perform method executes the defined sequence of touch actions.

5. Flick (Swipe) Gesture

Flick gestures in Appium are similar to swiping but are typically used for faster scrolling. The flick method allows testers to simulate quick and decisive scrolls in both vertical and horizontal directions. The flick method is used to simulate rapid and abrupt scrolling gestures, either vertically or horizontally. It’s suitable for scenarios where a quick swipe is needed, such as navigating through a long list or gallery.

Example:

Java

// Perform a flick gesture to simulate a swipe up
  driver.flick(0, -1);

Explanation:

1. driver refers to an instance of the Appium driver, which is controlling the automation on the mobile device.
2. flick is a method provided by Appium for performing flick or swipe gestures.
3. The parameters (0, -1) represent the direction and distance of the flick gesture.
   • The 0 in the X-axis means no horizontal movement (no movement left or right).
   • The -1 in the Y-axis means a negative movement in the vertical direction, suggesting an upward swipe.

6. MobileElement ScrollIntoView

For Appium scripts interacting with specific elements, the scrollIntoView method is handy. It ensures that a particular element is brought into the viewable area, making it accessible for further interactions.

Example:

Java

MobileElement targetElement = driver.findElement(MobileBy.id("targetElementId"));

// Ensure the target element is brought into view
targetElement.scrollIntoView();

Let’s break down the code step by step:

1. Locate the Target Element by ID: MobileElement targetElement = driver.findElement(MobileBy.id(“targetElementId”));
   • This line uses the findElement method to locate the target element in the mobile app.
   • MobileBy.id(“targetElementId”) is a locator strategy that finds an element using its ID. Replace “targetElementId” with the actual ID of the element you want to interact with.
2. Ensure the Target Element is Brought into View: targetElement.scrollIntoView();
   • This line calls the scrollIntoView method on the targetElement. This method is a part of the Appium library.
   • The purpose is to ensure that the target element is scrolled into the viewable area on the screen. This is useful when the element is not initially visible.

Choosing the Right Strategy

The choice of an Appium scroll strategy depends on factors such as the application under test, the type of content and the desired testing scenario.

1. For General Scrolling

• Coordinates or JSON wire protocol actions can be suitable for straightforward scrolling needs.
• UiScrollable is a robust choice for android applications with complex view hierarchies.

2. For Targeted Element Interaction

Use scrollIntoView when the goal is to bring a specific element into view for interaction.

3. For Dynamic and Multi-Touch Scrolling

Touch actions and flick gestures are effective for scenarios that require dynamic or rapid scrolling.

It’s essential to consider the unique characteristics of the application and adapt the scroll strategy accordingly. Additionally, considering the platform-specific implementations, such as UiScrollable for android and touch actions for both platforms, ensures compatibility and consistency across devices.

Handling Common Challenges

1. Wait for Elements to Load: Implement appropriate waits to ensure that elements are loaded before attempting to scroll. This avoids potential issues where elements are not present in the current view.
2. Adjust Scroll Distance: Experiment with the scroll distance to find the optimal value for your application. This is particularly important for scroll strategies that rely on coordinates or flick gestures.
3. Handle Infinite Scrolling: For scenarios with infinite scrolling, consider using a loop or recursive function to continue scrolling until a specific condition or element is met.
4. Debugging: Leverage Appium’s logging capabilities and inspect the application’s UI hierarchy to understand the structure and identify scrollable elements.

Conclusion

To automate mobile apps effectively with Appium, it’s crucial to know how to scroll in different situations. Appium offers various scroll strategies to handle different testing scenarios, whether it’s simple scrolling or dealing with dynamic content. Picking the right strategy based on your app’s features helps ensure thorough testing and script reliability. Regular testing, adjusting to any app changes, and exploring Appium’s features regularly are key to successful and efficient mobile testing practices.