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
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).
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`
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)
Reverts: flutter/flutter#148238
Initiated by: zanderso
Reason for reverting: Failures in post submit https://logs.chromium.org/logs/flutter/buildbucket/cr-buildbucket/8748025189669617649/+/u/run_test.dart_for_web_canvaskit_tests_shard_and_subshard_3/stdout
Original PR Author: justinmc
Reviewed By: {hellohuanlin}
This change reverts the following previous change:
Reland of https://github.com/flutter/flutter/pull/143002, which was reverted in https://github.com/flutter/flutter/pull/148237 due to unresolved docs references. Not sure why those weren't caught in presubmit.
```
dartdoc:stdout: Generating docs for package flutter...
dartdoc:stderr: error: unresolved doc reference [TextInput.showSystemContextMenu]
dartdoc:stderr: from widgets.MediaQueryData.supportsShowingSystemContextMenu: (file:///b/s/w/ir/x/w/flutter/packages/flutter/lib/src/widgets/media_query.dart:579:14)
dartdoc:stderr: in documentation inherited from widgets.MediaQueryData.supportsShowingSystemContextMenu: (file:///b/s/w/ir/x/w/flutter/packages/flutter/lib/src/widgets/media_query.dart:579:14)
dartdoc:stderr: error: unresolved doc reference [showSystemContextMenu]
dartdoc:stderr: from services.SystemContextMenuController.hide: (file:///b/s/w/ir/x/w/flutter/packages/flutter/lib/src/services/text_input.dart:2554:16)
dartdoc:stderr: error: unresolved doc reference [hideSystemContextMenu]
dartdoc:stderr: from services.SystemContextMenuController.show: (file:///b/s/w/ir/x/w/flutter/packages/flutter/lib/src/services/text_input.dart:2509:16)
```
It's now possible to use the native-rendered text selection context menu on iOS. This sacrifices customizability in exchange for avoiding showing a notification when the user presses "Paste". It's off by default, but to enable, see the example system_context_menu.0.dart.
Reverts: flutter/flutter#143002
Initiated by: cbracken
Reason for reverting: unresolved docs links. See failure here: https://ci.chromium.org/ui/p/flutter/builders/prod/Linux%20docs_test/16540/overview
```
dartdoc:stdout: Generating docs for package flutter...
dartdoc:stderr: error: unresolved doc reference [TextInput.showSystemContextMenu]
dartdoc:stderr: from widgets.MediaQueryData.supportsShowingSystemContextMenu: (file:///b/s/w/ir/x/w/flutter/packages/flutt
Original PR Author: justinmc
Reviewed By: {Renzo-Olivares, hellohuanlin}
This change reverts the following previous change:
In order to work around the fact that iOS 15 shows a notification on pressing Flutter's paste button (https://github.com/flutter/flutter/issues/103163), this PR allows showing the iOS system context menu in text fields.
<img width="385" alt="Screenshot 2024-02-06 at 11 52 25 AM" src="https://github.com/flutter/flutter/assets/389558/d82e18ee-b8a3-4082-9225-cf47fa7f3674">
It is currently opt-in, which a user would typically do like this (also in example system_context_menu.0.dart):
```dart
contextMenuBuilder: (BuildContext context, EditableTextState editableTextState) {
// If supported, show the system context menu.
if (SystemContextMenu.isSupported(context)) {
return SystemContextMenu.editableText(
editableTextState: editableTextState,
);
}
// Otherwise, show the flutter-rendered context menu for the current
// platform.
return AdaptiveTextSelectionToolbar.editableText(
editableTextState: editableTextState,
);
},
```
Requires engine PR https://github.com/flutter/engine/pull/50095.
## API changes
### SystemContextMenu
A widget that shows the system context menu when built, and removes it when disposed. The main high-level way that most users would use this PR. Only works on later versions of iOS.
### SystemContextMenuController
Used under the hood to hide and show a system context menu. There can only be one visible at a time.
### MediaQuery.supportsShowingSystemContextMenu
Sent by the iOS embedder to tell the framework whether or not the platform supports showing the system context menu. That way the framework, or Flutter developers, can decide to show a different menu.
### `flutter/platform ContextMenu.showSystemContextMenu`
Sent by the framework to show the menu at a given `targetRect`, which is the current selection rect.
### `flutter/platform ContextMenu.hideSystemContextMenu`
Sent by the framework to hide the menu. Typically not needed, because the platform will hide the menu when the user taps outside of it and after the user presses a button, but it handles edge cases where the user programmatically rebuilds the context menu, for example.
### `flutter/platform System.onDismissSystemContextMenu`
Sent by the iOS embedder to indicate that the system context menu has been hidden by the system, such as when the user taps outside of the menu. This is useful when there are multiple instances of SystemContextMenu, such as with multiple text fields.
It's now possible to use the native-rendered text selection context menu on iOS. This sacrifices customizability in exchange for avoiding showing a notification when the user presses "Paste". It's off by default, but to enable, see the example system_context_menu.0.dart.
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Updates `examples/api/lib/widgets/animated_size/animated_size.0.dart` API example by using `SizedBox` to size the surrounding of the `FlutterLogo` while setting the constant `FlutterLogo` size. This was done because `FlutterLogo` already has size animation under the hood, and the main goal of this example is to show `AnimatedSize` usage
- Adds test for `examples/api/lib/widgets/animated_size/animated_size.0.dart`
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Updates `examples/api/lib/widgets/async/stream_builder.0.dart`
- Adds test for `examples/api/lib/widgets/async/stream_builder.0.dart`
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Fixes name of the `examples/api/lib/widgets/shortcuts/single_activator.single_activator.0.dart`
- Adds tests for `examples/api/lib/widgets/shortcuts/single_activator.0.dart`
Here's another PR with a couple of typos fixed. As you can see there was a typo in _fileReferenceI**n**dentifiers_, in class _ParsedProjectInfo._ Maybe we should do some check on that since I'm not sure if that property is used somewhere outside Flutter?
Reverts: flutter/flutter#139164
Initiated by: chunhtai
Reason for reverting: hard breaking change
Original PR Author: chunhtai
Reviewed By: {justinmc}
This change reverts the following previous change:
Adds a generic type and pop result to popscope and its friend.
The use cases are to be able to capture the result when the pop is called.
migration guide: https://github.com/flutter/website/pull/9872
Adds a generic type and pop result to popscope and its friend.
The use cases are to be able to capture the result when the pop is called.
migration guide: https://github.com/flutter/website/pull/9872
This PR contributes to https://github.com/flutter/flutter/issues/130459
### Description
- Updates `examples/api/lib/material/material_state/material_state_mouse_cursor.0.dart` to allow enable/disable `ListTile` in tests;
- Adds tests for `examples/api/lib/material/material_state/material_state_mouse_cursor.0.dart`.
This change adds support for triple click to select a paragraph at the clicked position and triple click + drag to extend the selection paragraph-by-paragraph when using the SelectionArea widget.
This PR also:
* Makes `Text` widgets a `SelectionContainer` if a parent `SelectionRegistrar` exists.
* Fixes issues with selectable ordering involving `WidgetSpan`s.
Fixes: https://github.com/flutter/flutter/issues/104552
`@visibleForOverriding` + `@protected` unfortunately does not catch the case where a `compute*` method was overridden in a subtype and the overide was called in that same type's implementation.
I did not add a `flutter_ignore` for this because it doesn't seem there will be false positives.
## Description
This adds some "See also" links to some docs for `TweenAnimationBuilder` and `ValueListenableBuilder`.
Also, moved a "snippet" example in `ValueListenableBuilder` into the examples directory as a Dartpad example.
## Tests
- Added test for the example.
This pull request introduces a new field named `helper` to the InputDecoration class. This field allows for specifying a widget containing contextual information about the InputDecorator.child's value. Unlike `helperText`, which accepts a plain string, `helper` supports widgets, enabling functionalities like tappable links for further explanation. This change aligns with the established pattern of `error`, `label`, `prefix`, and `suffix`.
fixes [#145163](https://github.com/flutter/flutter/issues/145163)
Fixes#138270.
Moves the majority of the logic of MaterialStateProperties down to the widgets layer, then has the existing Material classes pull from the widgets versions.
This pull request is part of the effort to solve issue #144903.
In the past, my efforts to reduce line length involved refactoring away from switch statements, but unlike [yesterday's PR](https://github.com/flutter/flutter/pull/144905), this one is full of switch statements that make things more concise!
Improved the smiley image TextButton example a little. Handling the case where the `Future.delayed` object that represents the button's one second long action is superseded by a second button press that triggers a new one-second action. This does complicate the example - just a little - but it's a little more robust. In case someone copy-and-pastes the code.
The TextButton example was recently updated: https://github.com/flutter/flutter/pull/144583
Reverts flutter/flutter#144001
Initiated by: Piinks
Reason for reverting: Failing goldens at the tip of tree
Original PR Author: QuncCccccc
Reviewed By: {HansMuller}
This change reverts the following previous change:
Original Description:
Reverts flutter/flutter#143973
This is a reland for #138521 with an updated g3fix(cl/605555997). Local test: cl/609608958.
## Description
This PR adds more documentation for `TextEditingController(String text)` constructor and it adds one example.
https://github.com/flutter/flutter/pull/96245 was a first improvement to the documentation.
https://github.com/flutter/flutter/issues/79495 tried to hide the cursor when an invalid selection is set but it was reverted.
https://github.com/flutter/flutter/pull/123777 mitigated the issue of having a default invalid selection: it takes care of setting a proper selection when a text field is focused and its controller selection is not initialized.
I will try changing the initial selection in another PR, but It will probably break several existing tests.
## Related Issue
Fixes https://github.com/flutter/flutter/issues/95978
## Tests
Adds 1 test for the new example.
Reland https://github.com/flutter/flutter/pull/141818 with a fix for a special case: If only `background` is specified for `TextButton.styleFrom` or `OutlinedButton.styleFrom` it applies the button's disabled state, i.e. as if the same value had been specified for disabledBackgroundColor.
The change relative to #141818 is the indicated line below:
```dart
final MaterialStateProperty<Color?>? backgroundColorProp = switch ((backgroundColor, disabledBackgroundColor)) {
(null, null) => null,
(_, null) => MaterialStatePropertyAll<Color?>(backgroundColor), // ADDED THIS LINE
(_, _) => _TextButtonDefaultColor(backgroundColor, disabledBackgroundColor),
};
```
This backwards incompatibility cropped up in an internal test, see internal Google issue b/323399158.
Reverts flutter/flutter#141818
Initiated by: XilaiZhang
This change reverts the following previous change:
Original Description:
Fixes https://github.com/flutter/flutter/issues/139456, https://github.com/flutter/flutter/issues/130335, https://github.com/flutter/flutter/issues/89563.
Two new properties have been added to ButtonStyle to make it possible to insert arbitrary state-dependent widgets in a button's background or foreground. These properties can be specified for an individual button, using the style parameter, or for all buttons using a button theme's style parameter.
The new ButtonStyle properties are `backgroundBuilder` and `foregroundBuilder` and their (function) types are:
```dart
typedef ButtonLayerBuilder = Widget Function(
BuildContext context,
Set<MaterialState> states,
Widget? child
);
```
The new builder functions are called whenever the button is built and the `states` parameter communicates the pressed/hovered/etc state fo the button.
## `backgroundBuilder`
Creates a widget that becomes the child of the button's Material and whose child is the rest of the button, including the button's `child` parameter. By default the returned widget is clipped to the Material's ButtonStyle.shape.
The `backgroundBuilder` can be used to add a gradient to the button's background. Here's an example that creates a yellow/orange gradient background:

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [Colors.orange, Colors.yellow]),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
Because the background widget becomes the child of the button's Material, if it's opaque (as it is in this case) then it obscures the overlay highlights which are painted on the button's Material. To ensure that the highlights show through one can decorate the background with an `Ink` widget. This version also overrides the overlay color to be (shades of) red, because that makes the highlights look a little nicer with the yellow/orange background.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
overlayColor: Colors.red,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return Ink(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [Colors.orange, Colors.yellow]),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
Now the button's overlay highlights are painted on the Ink widget. An Ink widget isn't needed if the background is sufficiently translucent. This version of the example creates a translucent backround widget.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
overlayColor: Colors.red,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [
Colors.orange.withOpacity(0.5),
Colors.yellow.withOpacity(0.5),
]),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
One can also decorate the background with an image. In this example, the button's background is an burlap texture image. The foreground color has been changed to black to make the button's text a little clearer relative to the mottled brown backround.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
foregroundColor: Colors.black,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return Ink(
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(burlapUrl),
fit: BoxFit.cover,
),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
The background widget can depend on the `states` parameter. In this example the blue/orange gradient flips horizontally when the button is hovered/pressed.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final Color color1 = Colors.blue.withOpacity(0.5);
final Color color2 = Colors.orange.withOpacity(0.5);
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(
colors: switch (states.contains(MaterialState.hovered)) {
true => <Color>[color1, color2],
false => <Color>[color2, color1],
},
),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
The preceeding examples have not included a BoxDecoration border because ButtonStyle already supports `ButtonStyle.shape` and `ButtonStyle.side` parameters that can be uesd to define state-dependent borders. Borders defined with the ButtonStyle side parameter match the button's shape. To add a border that changes color when the button is hovered or pressed, one must specify the side property using `copyWith`, since there's no `styleFrom` shorthand for this case.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
foregroundColor: Colors.indigo,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final Color color1 = Colors.blue.withOpacity(0.5);
final Color color2 = Colors.orange.withOpacity(0.5);
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(
colors: switch (states.contains(MaterialState.hovered)) {
true => <Color>[color1, color2],
false => <Color>[color2, color1],
},
),
),
child: child,
);
},
).copyWith(
side: MaterialStateProperty.resolveWith<BorderSide?>((Set<MaterialState> states) {
if (states.contains(MaterialState.hovered)) {
return BorderSide(width: 3, color: Colors.yellow);
}
return null; // defer to the default
}),
),
child: Text('Text Button'),
)
```
Although all of the examples have created a ButtonStyle locally and only applied it to one button, they could have configured the `ThemeData.textButtonTheme` instead and applied the style to all TextButtons. And, of course, all of this works for all of the ButtonStyleButton classes, not just TextButton.
## `foregroundBuilder`
Creates a Widget that contains the button's child parameter. The returned widget is clipped by the button's [ButtonStyle.shape] inset by the button's [ButtonStyle.padding] and aligned by the button's [ButtonStyle.alignment].
The `foregroundBuilder` can be used to wrap the button's child, e.g. with a border or a `ShaderMask` or as a state-dependent substitute for the child.
This example adds a border that's just applied to the child. The border only appears when the button is hovered/pressed.

```dart
ElevatedButton(
onPressed: () {},
style: ElevatedButton.styleFrom(
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final ColorScheme colorScheme = Theme.of(context).colorScheme;
return DecoratedBox(
decoration: BoxDecoration(
border: states.contains(MaterialState.hovered)
? Border(bottom: BorderSide(color: colorScheme.primary))
: Border(), // essentially "no border"
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
The foregroundBuilder can be used with `ShaderMask` to change the way the button's child is rendered. In this example the ShaderMask's gradient causes the button's child to fade out on top.

```dart
ElevatedButton(
onPressed: () { },
style: ElevatedButton.styleFrom(
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final ColorScheme colorScheme = Theme.of(context).colorScheme;
return ShaderMask(
shaderCallback: (Rect bounds) {
return LinearGradient(
begin: Alignment.bottomCenter,
end: Alignment.topCenter,
colors: <Color>[
colorScheme.primary,
colorScheme.primaryContainer,
],
).createShader(bounds);
},
blendMode: BlendMode.srcATop,
child: child,
);
},
),
child: const Text('Elevated Button'),
)
```
A commonly requested configuration for butttons has the developer provide images, one for pressed/hovered/normal state. You can use the foregroundBuilder to create a button that fades between a normal image and another image when the button is pressed. In this case the foregroundBuilder doesn't use the child it's passed, even though we've provided the required TextButton child parameter.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final String url = states.contains(MaterialState.pressed) ? smiley2Url : smiley1Url;
return AnimatedContainer(
width: 100,
height: 100,
duration: Duration(milliseconds: 300),
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(url),
fit: BoxFit.contain,
),
),
);
},
),
child: Text('No Child'),
)
```
In this example the button's default overlay appears when the button is hovered and pressed. Another image can be used to indicate the hovered state and the default overlay can be defeated by specifying `Colors.transparent` for the `overlayColor`:

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
overlayColor: Colors.transparent,
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
String url = states.contains(MaterialState.hovered) ? smiley3Url : smiley1Url;
if (states.contains(MaterialState.pressed)) {
url = smiley2Url;
}
return AnimatedContainer(
width: 100,
height: 100,
duration: Duration(milliseconds: 300),
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(url),
fit: BoxFit.contain,
),
),
);
},
),
child: Text('No Child'),
)
```
Fixes https://github.com/flutter/flutter/issues/139456, https://github.com/flutter/flutter/issues/130335, https://github.com/flutter/flutter/issues/89563.
Two new properties have been added to ButtonStyle to make it possible to insert arbitrary state-dependent widgets in a button's background or foreground. These properties can be specified for an individual button, using the style parameter, or for all buttons using a button theme's style parameter.
The new ButtonStyle properties are `backgroundBuilder` and `foregroundBuilder` and their (function) types are:
```dart
typedef ButtonLayerBuilder = Widget Function(
BuildContext context,
Set<MaterialState> states,
Widget? child
);
```
The new builder functions are called whenever the button is built and the `states` parameter communicates the pressed/hovered/etc state fo the button.
## `backgroundBuilder`
Creates a widget that becomes the child of the button's Material and whose child is the rest of the button, including the button's `child` parameter. By default the returned widget is clipped to the Material's ButtonStyle.shape.
The `backgroundBuilder` can be used to add a gradient to the button's background. Here's an example that creates a yellow/orange gradient background:

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [Colors.orange, Colors.yellow]),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
Because the background widget becomes the child of the button's Material, if it's opaque (as it is in this case) then it obscures the overlay highlights which are painted on the button's Material. To ensure that the highlights show through one can decorate the background with an `Ink` widget. This version also overrides the overlay color to be (shades of) red, because that makes the highlights look a little nicer with the yellow/orange background.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
overlayColor: Colors.red,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return Ink(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [Colors.orange, Colors.yellow]),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
Now the button's overlay highlights are painted on the Ink widget. An Ink widget isn't needed if the background is sufficiently translucent. This version of the example creates a translucent backround widget.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
overlayColor: Colors.red,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(colors: [
Colors.orange.withOpacity(0.5),
Colors.yellow.withOpacity(0.5),
]),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
One can also decorate the background with an image. In this example, the button's background is an burlap texture image. The foreground color has been changed to black to make the button's text a little clearer relative to the mottled brown backround.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
foregroundColor: Colors.black,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
return Ink(
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(burlapUrl),
fit: BoxFit.cover,
),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
The background widget can depend on the `states` parameter. In this example the blue/orange gradient flips horizontally when the button is hovered/pressed.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final Color color1 = Colors.blue.withOpacity(0.5);
final Color color2 = Colors.orange.withOpacity(0.5);
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(
colors: switch (states.contains(MaterialState.hovered)) {
true => <Color>[color1, color2],
false => <Color>[color2, color1],
},
),
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
The preceeding examples have not included a BoxDecoration border because ButtonStyle already supports `ButtonStyle.shape` and `ButtonStyle.side` parameters that can be uesd to define state-dependent borders. Borders defined with the ButtonStyle side parameter match the button's shape. To add a border that changes color when the button is hovered or pressed, one must specify the side property using `copyWith`, since there's no `styleFrom` shorthand for this case.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
foregroundColor: Colors.indigo,
backgroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final Color color1 = Colors.blue.withOpacity(0.5);
final Color color2 = Colors.orange.withOpacity(0.5);
return DecoratedBox(
decoration: BoxDecoration(
gradient: LinearGradient(
colors: switch (states.contains(MaterialState.hovered)) {
true => <Color>[color1, color2],
false => <Color>[color2, color1],
},
),
),
child: child,
);
},
).copyWith(
side: MaterialStateProperty.resolveWith<BorderSide?>((Set<MaterialState> states) {
if (states.contains(MaterialState.hovered)) {
return BorderSide(width: 3, color: Colors.yellow);
}
return null; // defer to the default
}),
),
child: Text('Text Button'),
)
```
Although all of the examples have created a ButtonStyle locally and only applied it to one button, they could have configured the `ThemeData.textButtonTheme` instead and applied the style to all TextButtons. And, of course, all of this works for all of the ButtonStyleButton classes, not just TextButton.
## `foregroundBuilder`
Creates a Widget that contains the button's child parameter. The returned widget is clipped by the button's [ButtonStyle.shape] inset by the button's [ButtonStyle.padding] and aligned by the button's [ButtonStyle.alignment].
The `foregroundBuilder` can be used to wrap the button's child, e.g. with a border or a `ShaderMask` or as a state-dependent substitute for the child.
This example adds a border that's just applied to the child. The border only appears when the button is hovered/pressed.

```dart
ElevatedButton(
onPressed: () {},
style: ElevatedButton.styleFrom(
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final ColorScheme colorScheme = Theme.of(context).colorScheme;
return DecoratedBox(
decoration: BoxDecoration(
border: states.contains(MaterialState.hovered)
? Border(bottom: BorderSide(color: colorScheme.primary))
: Border(), // essentially "no border"
),
child: child,
);
},
),
child: Text('Text Button'),
)
```
The foregroundBuilder can be used with `ShaderMask` to change the way the button's child is rendered. In this example the ShaderMask's gradient causes the button's child to fade out on top.

```dart
ElevatedButton(
onPressed: () { },
style: ElevatedButton.styleFrom(
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final ColorScheme colorScheme = Theme.of(context).colorScheme;
return ShaderMask(
shaderCallback: (Rect bounds) {
return LinearGradient(
begin: Alignment.bottomCenter,
end: Alignment.topCenter,
colors: <Color>[
colorScheme.primary,
colorScheme.primaryContainer,
],
).createShader(bounds);
},
blendMode: BlendMode.srcATop,
child: child,
);
},
),
child: const Text('Elevated Button'),
)
```
A commonly requested configuration for butttons has the developer provide images, one for pressed/hovered/normal state. You can use the foregroundBuilder to create a button that fades between a normal image and another image when the button is pressed. In this case the foregroundBuilder doesn't use the child it's passed, even though we've provided the required TextButton child parameter.

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
final String url = states.contains(MaterialState.pressed) ? smiley2Url : smiley1Url;
return AnimatedContainer(
width: 100,
height: 100,
duration: Duration(milliseconds: 300),
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(url),
fit: BoxFit.contain,
),
),
);
},
),
child: Text('No Child'),
)
```
In this example the button's default overlay appears when the button is hovered and pressed. Another image can be used to indicate the hovered state and the default overlay can be defeated by specifying `Colors.transparent` for the `overlayColor`:

```dart
TextButton(
onPressed: () {},
style: TextButton.styleFrom(
overlayColor: Colors.transparent,
foregroundBuilder: (BuildContext context, Set<MaterialState> states, Widget? child) {
String url = states.contains(MaterialState.hovered) ? smiley3Url : smiley1Url;
if (states.contains(MaterialState.pressed)) {
url = smiley2Url;
}
return AnimatedContainer(
width: 100,
height: 100,
duration: Duration(milliseconds: 300),
decoration: BoxDecoration(
image: DecorationImage(
image: NetworkImage(url),
fit: BoxFit.contain,
),
),
);
},
),
child: Text('No Child'),
)
```
Fixes #140770 and #103124
Adds the possibility of passing a height and width to icons. And also a margin for the distance of the lines between the icons.
fixes [`RouteObserver` example throws an error](https://github.com/flutter/flutter/issues/141078)
### Description
This updates the `RouteObserver` example from snippet to Dartpad example and fixes the error when running the code snippet
fixes https://github.com/flutter/flutter/issues/138289
---
SegmentedButtom.styleFrom has been added to the segment button, so there is no longer any need to the button style from the beginning. It works like ElevatedButton.styleFrom only I added selectedForegroundColor, selectedBackgroundColor. In this way, the user will be able to change the color first without checking the MaterialState states. I added tests of the same controls.
#129215 I opened this problem myself, but I was rejected because I handled too many items in a PR. For now, I wrote a structure that only handles MaterialStates instead of users.
old (still avaliable)
<img width="626" alt="image" src="https://github.com/flutter/flutter/assets/65075121/9446b13b-c355-4d20-bda2-c47a23d42d4f">
new (just an option for developer)
<img width="483" alt="image" src="https://github.com/flutter/flutter/assets/65075121/0a645257-4c83-4029-9484-bd746c02265f">
### Code sample
<details>
<summary>expand to view the code sample</summary>
```dart
import 'package:flutter/material.dart';
/// Flutter code sample for [SegmentedButton].
void main() {
runApp(const SegmentedButtonApp());
}
enum Calendar { day, week, month, year }
class SegmentedButtonApp extends StatefulWidget {
const SegmentedButtonApp({super.key});
@override
State<SegmentedButtonApp> createState() => _SegmentedButtonAppState();
}
class _SegmentedButtonAppState extends State<SegmentedButtonApp> {
Calendar calendarView = Calendar.day;
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData(useMaterial3: true),
home: Scaffold(
body: Center(
child: SegmentedButton<Calendar>(
style: SegmentedButton.styleFrom(
foregroundColor: Colors.amber,
visualDensity: VisualDensity.comfortable,
),
// style: const ButtonStyle(
// foregroundColor: MaterialStatePropertyAll<Color>(Colors.deepPurple),
// visualDensity: VisualDensity.comfortable,
// ),
segments: const <ButtonSegment<Calendar>>[
ButtonSegment<Calendar>(
value: Calendar.day,
label: Text('Day'),
icon: Icon(Icons.calendar_view_day)),
ButtonSegment<Calendar>(
value: Calendar.week,
label: Text('Week'),
icon: Icon(Icons.calendar_view_week)),
ButtonSegment<Calendar>(
value: Calendar.month,
label: Text('Month'),
icon: Icon(Icons.calendar_view_month)),
ButtonSegment<Calendar>(
value: Calendar.year,
label: Text('Year'),
icon: Icon(Icons.calendar_today)),
],
selected: <Calendar>{calendarView},
onSelectionChanged: (Set<Calendar> newSelection) {
setState(() {
calendarView = newSelection.first;
});
},
),
),
),
);
}
}
```
</details>
Thanks so much for approving the previous PR (#139048) a couple weeks ago!
This one is the same, except it's covering files in `examples/` and `packages/flutter/lib/src/animation/`.
(solving issue #136139)
This change fixes issues with screen order comparison logic when rects are encompassed within each other. This was causing issues when trying to select text that includes inline `WidgetSpan`s inside of a `SelectionArea`.
* Adds `boundingBoxes` to `Selectable` for a more precise hit testing region.
Fixes#132821
Fixes updating selection edge by word boundary when widget spans are involved.
Fixes crash when sending select word selection event to an unselectable element.
Reverts flutter/flutter#137945
Initiated by: HansMuller
This change reverts the following previous change:
Original Description:
This PR introduces `AnimationStyle`, it is used to override default animation curves and durations in several widgets.
fixes [Add the ability to customize MaterialApp theme animation duration](https://github.com/flutter/flutter/issues/78372)
fixes [Allow customization of showMenu transition animation curves and duration](https://github.com/flutter/flutter/issues/135638)
Here is an example where popup menu curve and transition duration is overriden:
```dart
popUpAnimationStyle: AnimationStyle(
curve: Easing.emphasizedAccelerate,
duration: Durations.medium4,
),
```
Set `AnimationStyle.noAnimation` to disable animation.
```dart
return MaterialApp(
themeAnimationStyle: AnimationStyle.noAnimation,
```
This PR introduces `AnimationStyle`, it is used to override default animation curves and durations in several widgets.
fixes [Add the ability to customize MaterialApp theme animation duration](https://github.com/flutter/flutter/issues/78372)
fixes [Allow customization of showMenu transition animation curves and duration](https://github.com/flutter/flutter/issues/135638)
Here is an example where popup menu curve and transition duration is overriden:
```dart
popUpAnimationStyle: AnimationStyle(
curve: Easing.emphasizedAccelerate,
duration: Durations.medium4,
),
```
Set `AnimationStyle.noAnimation` to disable animation.
```dart
return MaterialApp(
themeAnimationStyle: AnimationStyle.noAnimation,
```
### Description
This PR intends to update `DraggableScrollableSheet` docs for Web and Desktop platforms. On these platforms, the vertical dragging gesture does not provide natural behavior similar to other desktop applications.
By adding a note before the sample code so users are aware that the sample code will not work as expected on Desktop and Web. Also, refer to the instructions if they still want to implement it on these platforms.
### Related issue
Fixes https://github.com/flutter/flutter/issues/111372
This example shows how to use `AnimationController` and
`SlideTransition` to create an animated digit like you might find on a
digital clock. New digit values slide into place from below, as the old
value slides upwards and out of view. Taps that occur while the
controller is already animating cause the controller's
`AnimationController.duration` to be reduced so that the visuals don't
fall behind.
You can try the example here:
https://dartpad.dev/?id=9553c20fe0fdb0c5447c1293e02400eb
Currently, `Switch.factory` delegates to `CupertinoSwitch` when platform
is iOS or macOS. This PR is to:
* have the factory configure the Material `Switch` for the expected look
and feel.
* introduce `Adaptation` class to customize themes for the adaptive
components.