Qun Cheng 6dd929ab28
Normalize Dialog theme (#153982)
This PR is to make preparations to make `DialogTheme` conform to Flutter's conventions for component themes:

* Added a `DialogThemeData` class which defines overrides for the defaults for `Dialog` properties.
* Added 2 `DialogTheme` constructor parameters: `DialogThemeData? data` and `Widget? child`. This is now the preferred way to configure a `DialogTheme`:
```
DialogTheme(
  data: DialogThemeData(color: xxx, elevation: xxx, ...),
  child: Dialog(...)
)
```
  These two properties are made nullable to not break existing apps which has customized `ThemeData.dialogTheme`.

* Changed the type of theme defaults from `DialogTheme` to `DialogThemeData`.

TODO:

* Fix internal failures.
* Change the type of `ThemeData.dialogTheme` from `DialogTheme` to `DialogThemeData`. This may cause breaking changes, a migration guide will be created.

Addresses the "theme normalization" sub project within https://github.com/flutter/flutter/issues/91772
2024-09-05 22:00:23 +00:00
..
2024-08-29 16:28:08 +00:00
2024-08-28 05:23:18 +00:00
2024-08-29 16:28:08 +00:00