The `theme` parameter of `Preview(...)` allows for developers to provide a callback that returns a `PreviewThemeData` instance which can contain theming data for Material and Cupertino widgets in both light and dark modes. The provided theme data will be injected into the widget tree and applied to the previewed widget. The `brightness` parameter allows for developers to specify an initial brightness setting (e.g., light vs dark mode) for the previewed widget. If not provided, the current system default is used. A new button has also been added to each widget preview card that allows for toggling between light and dark mode for individual previews. **Demo:** https://github.com/user-attachments/assets/f0a4a3bc-25d2-49b0-a5f6-9149eccfc1d4 Fixes https://github.com/flutter/flutter/issues/166436 Fixes https://github.com/flutter/flutter/issues/166275 Fixes https://github.com/flutter/flutter/issues/166279 Fixes https://github.com/flutter/flutter/issues/166437
external_textures
Tests external texture rendering between a native1 platform and Flutter.
Part of Flutter's API for plugins includes passing external textures, or textures
created outside of Flutter, to Flutter, typically using the Texture
widget. This is useful for plugins that render video, or for plugins that
interact with the camera.
For example:
Because external textures are created outside of Flutter, there is often subtle translation that needs to happen between the native platform and Flutter, which is hard to observe. These integration tests are designed to help catch these subtle translation issues.
How it works
- Each
lib/*_main.dartfile is a Flutter app instrumenting a test case. - There is a corresponding
test_driver/*_test.dartthat runs assertions.
To run the test cases locally, use flutter drive2:
flutter drive lib/frame_rate_main.dart --driver test_driver/frame_rate_test.dart
Tip
On CI, the test cases are run within our device lab.
See
devicelab/lib/tasks/integration_tests.dartand search forcreateExternalUiFrameRateIntegrationTest.The actual tests are run by task runners: