Ben Konyi 3595e7dad0
[ Widget Preview ] Add support for theme and brightness properties on Preview (#167001)
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
2025-04-15 17:51:40 +00:00
..
2024-12-19 20:06:21 +00:00

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.dart file is a Flutter app instrumenting a test case.
  • There is a corresponding test_driver/*_test.dart that 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.dart and search for createExternalUiFrameRateIntegrationTest.

The actual tests are run by task runners:


  1. Only iOS and Android. ↩︎

  2. Unfortunately documentation is quite limited. See #142021. ↩︎