A sliver that is pinned to the start of its `CustomScrollView` and reacts to scrolling by resizing between the intrinsic sizes of its min and max extent prototypes.
The minimum and maximum sizes of this sliver are defined by `minExtentPrototype` and `maxExtentPrototype`, a pair of widgets that are laid out once. You can use `SizedBox` widgets to define the size limits.
This sliver is preferable to the general purpose `SliverPersistentHeader` for its relatively narrow use case because there's no need to create a `SliverPersistentHeaderDelegate` or to predict the header's minimum or maximum size.
The sample shows how this sliver's two extent prototype properties can be used to create a resizing header whose minimum and maximum sizes match small and large configurations of the same header widget.
https://github.com/flutter/flutter/assets/1377460/fa7ced98-9d92-4d13-b093-50392118c213
Related sliver utility PRs: https://github.com/flutter/flutter/pull/143538, https://github.com/flutter/flutter/pull/143196, https://github.com/flutter/flutter/pull/127340.
This PR adds `AnimatedList.separated`. A widget like an AnimatedList with animated separators. `animated_list_separated.0.dart` extends `animated_list.0.dart` to work with `AnimatedList.separated`
Related issue: https://github.com/flutter/flutter/issues/48226
The scroll notification events reported for a press-drag-release gesture within a scrollable on a touch screen device begin with a `ScrollStartNotification`, followed by a series of `ScrollUpdateNotifications`, and conclude with a `ScrollEndNotification`. This protocol can be used to defer work until an interactive scroll gesture ends. For example, you might defer updating a scrollable's contents via network requests until the scroll has ended, or you might want to automatically auto-scroll at that time.
In the example that follows the CustomScrollView automatically scrolls so that the last partially visible fixed-height item is completely visible when the scroll gesture ends. Many iOS applications do this kind of thing. It only makes sense to auto-scroll when the user isn't actively dragging the scrollable around.
It's easy enough to do this by reacting to a ScrollEndNotifcation by auto-scrolling to align the last fixed-height list item ([source code](https://gist.github.com/HansMuller/13e2a7adadc9afb3803ba7848b20c410)).
https://github.com/flutter/flutter/assets/1377460/a6e6fc77-6742-4f98-81ba-446536535f73
Dragging the scrollbar thumb in a desktop application is a similar user gesture. Currently it's not possible to defer work or auto-scroll (or whatever) while the scrollable is actively being dragged via the scrollbar thumb because each scrollbar thumb motion is mapped to a scroll start - scroll update - scroll end series of notifications. On a desktop platform, the same code behaves quite differently when the scrollbar thumb is dragged.
https://github.com/flutter/flutter/assets/1377460/2593d8a3-639c-407f-80c1-6e6f67fb8c5f
The stream of scroll-end events triggers auto-scrolling every time the thumb moves. From the user's perspective this feels like a losing struggle.
One can also detect the beginning and end of a touch-drag by listening to the value of a ScrollPosition's `isScrollingNotifier`. This approach suffers from a similar problem: during a scrollbar thumb-drag, the `isScrollingNotifier` value isn't updated at all.
This PR refactors the RawScrollbar implementation to effectively use a ScrollDragController to manage scrolls caused by dragging the scrollbar's thumb. Doing so means that dragging the thumb will produce the same notifications as dragging the scrollable on a touch device.
Now desktop applications can choose to respond to scrollbar thumb drags in the same that they respond to drag scrolling on a touch screen. With the changes included here, the desktop or web version of the app works as expected, whether you're listing to scroll notifications or the scroll position's `isScrollingNotifier`.
https://github.com/flutter/flutter/assets/1377460/67435c40-a866-4735-a19b-e3d68eac8139
This PR also makes the second [ScrollPosition API doc example](https://api.flutter.dev/flutter/widgets/ScrollPosition-class.html#cupertino.ScrollPosition.2) work as expected when used with the DartPad that's part of API doc page.
Desktop applications also see scroll start-update-end notifications due to the mouse wheel. There is no touch screen analog for the mouse wheel, so an application that wanted to enable this kind of auto-scrolling alignment would have to include a heuristic that dealt with the sequence of small scrolls triggered by the mouse wheel. Here's an example of that: [source code](https://gist.github.com/HansMuller/ce5c474a458f5f4bcc07b0d621843165). This version of the app does not auto-align in response to small changes, wether they're triggered by dragging the scrollbar thumb of the mouse wheel.
Related sliver utility PRs: https://github.com/flutter/flutter/pull/143538, https://github.com/flutter/flutter/pull/143196, https://github.com/flutter/flutter/pull/143325.
The current MenuAnchor example in the API Docs is comprehensive and complicated for beginners. I have added a simple bare bone example without shortcuts, enums, etc in examples/api/lib/material/menu_anchor/ as `menu_anchor.3.dart`. The example is contributed by @mafreud
Fixes https://github.com/flutter/flutter/issues/148104
Manual recreation of https://github.com/flutter/flutter/pull/148911
Entire PR is just the output of
```
flutter update-packages --force-upgrade
```
followed by (run from the root of the flutter repo)
```
find . -type d -name 'android' | dart dev/tools/bin/generate_gradle_lockfiles.dart --no-gradle-generation --no-exclusion
```
Adds tests for `relative_positioned_transition`, `positioned_transition`, `sliver_fade_transition`, `align_transition`, `animated_builder`, `rotation_transition`, `animated_widget`, `slide_transition`, `listenable_builder`, `scale_transition`, `default_text_style_transition`, `decorated_box_transition`, `size_transition` api examples. Makes double type in the `align_transition` example explicit.
A test for `fade_transition` is already in currently open #148178.
Part of #130459.
Adds tests to the last two Snack Bar examples as part of #130459. Makes the [last example](https://api.flutter.dev/flutter/material/SnackBar-class.html#material.SnackBar.3) more usable through the use of standard widgets and visual hierarchy. Constraints on options that are not required by the SnackBar contract have been removed (Overflow threshold works on fixed SnackBars).
Contributes to https://github.com/flutter/flutter/issues/130459
It adds test for
- `examples/api/lib/material/scaffold/scaffold.0.dart`
- `examples/api/lib/material/scaffold/scaffold.2.dart`
It also modifies the `scaffold.1_test.dart` because the only difference with scaffold 0 is the background color, so I figured the test should include it
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Updates `examples/api/lib/widgets/restoration_properties/restorable_value.0.dart` to meet the latest API examples structure
- Adds tests for `examples/api/lib/widgets/restoration_properties/restorable_value.0.dart`
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Updates `examples/api/lib/widgets/actions/actions.0.dart` to meet the latest API examples structure
- Adds tests for `examples/api/lib/widgets/actions/actions.0.dart`
### fixes#136139
<br>
<details open> <summary><b>getting sentimental in the PR description</b> (click to collapse)<br><br></summary>
The past 7 months have been quite the journeyâI made some huge blunders and some huge accomplishmentsâa very fun time overall.
I really appreciate the people who took the time to perform code review for my refactoring shenanigans: **christopherfujino**, **andrewkolos**, **LongCatIsLooong**, **gspencergoog**, **loic-sharma**, **Piinks**, **bernaferrari**, **bartekpacia**, **bleroux**, **kevmoo**, **rakudrama**, **XilaiZhang**, **QuncCccccc**, **MominRaza**, and **victorsanni**.
And a huge shoutout to 2 individuals:
- @justinmc, for offering to sponsor me for commit access (words could not describe my excitement)
- @goderbauer, for being super duper proactive and consistent with code review
<br>
</details>
This pull request makes 13 "switch statements â switch expressions" PRs in total, reducing the LOC in this repo by **1,974**!
From now on, I'll make sure to request a test exemption for each refactoring PR ð
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Updates `examples/api/lib/widgets/shared_app_data/shared_app_data.0.dart` to meet latest API examples structure
- Updates `examples/api/lib/widgets/shared_app_data/shared_app_data.1.dart` to meet latest API examples structure
- Adds tests for `examples/api/lib/widgets/shared_app_data/shared_app_data.0.dart`
- Adds tests for `examples/api/lib/widgets/shared_app_data/shared_app_data.1.dart`
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Corrects the name for `examples/api/test/widgets/shortcuts/logical_key_set.0_test.dart` test file
- Update tests for `examples/api/lib/widgets/shortcuts/logical_key_set.0.dart`
PR #147801 introduced some convenient `AnimationStatus` getters, but I just realized that `AnimationController` now has 2 getters for the same thing: `isAnimating` and `isRunning`.
The intent of this pull request is to correct that mistake, and implement the getters in the appropriate places.
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Updates `examples/api/lib/material/tab_controller/tab_controller.1.dart` to properly remove the listener from the `TabController`
- Adds tests for `examples/api/lib/material/tab_controller/tab_controller.1.dart`
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Adds disposal of the `CurvedAnimation` in `examples/api/test/widgets/transitions/fade_transition.0.dart`
- Adds tests for `examples/api/lib/widgets/transitions/fade_transition.0.dart`
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Adds tests for `examples/api/lib/material/scaffold/scaffold.of.0.dart`
- Adds tests for `examples/api/lib/material/scaffold/scaffold.of.1.dart`
*Use `super.key` instead of manually passing the `Key` parameter using super(key: key) in the constructors.*
Since if you create a widget the new default will use `super.key` instead of `Key? key : super(key: key)` this small change is to maintain the consistency, it has no semantic change
also there are some other places that might need to be updated:
this file for example generate l10n project and it has all the dart code as String, it might have tests that validate the output somewhere that I might miss, also there are some other places like the `_Segment` class where it require `ValueKey` instead if `Key` so I didn't update them (even though it's possible)
