Cookbook chevron_right Testing chevron_right Widget chevron_right Tap, drag, and enter text Tap, drag, and enter text How to test widgets for user interaction. Cookbook chevron_right Testing chevron_right Unit chevron_right Mocking Mock dependencies using Mockito Use the Mockito package to mimic the behavior of services for testing. This test makes sure that the orientation is landscape and that only 3 columns of data appear in the app: In test/widget_test.dart, inside of the Orientation group, add the following test after the landscape test: Learn how to use the Flutter Widget Previewer to see your widgets render in real-time, separate from your full app. To locate widgets in a test environment, use the Finder classes. While it's possible to write your own Finder classes, it's generally more convenient to locate widgets using the tools provided by the flutter_test package. During a flutter run session on a widget test, you can also interactively tap parts of the screen for the Flutter tool to print the suggested Finder. This recipe looks at the. The integration_test package lets you: Use the flutter drive command to run tests on a physical device or emulator. Run on Firebase Test Lab, to automate testing on a variety of devices. Use flutter_test APIs to write tests in a style similar to widget tests. In the introduction to unit testing recipe, you learned how to test Dart classes using the test package. To test widget classes, you need a few additional tools provided by the flutter_test package, which ships with the Flutter SDK. The flutter_test package provides the following tools for testing widgets: The WidgetTester allows building and interacting with widgets in a test environment. The. How to handle scrolling in a widget test. Now, you can write a test. In this example, scroll through the list of items and verify that a particular item exists in the list. The WidgetTester class provides the scrollUntilVisible () method, which scrolls through a list until a specific widget is visible. This is useful because the height of the items in the list can change depending on the. Testing a widget involves multiple classes and requires a test environment that provides the appropriate widget lifecycle context. For example, the Widget being tested should be able to receive and respond to user actions and events, perform layout, and instantiate child widgets. Handle scrolling How to handle scrolling in a widget test. Many apps feature lists of content, from email clients to music apps and beyond. To verify that lists contain the ex.