Bumps [github/codeql-action](https://github.com/github/codeql-action) from 3.23.2 to 3.24.0.
<details>
<summary>Changelog</summary>
<p><em>Sourced from <a href="https://github.com/github/codeql-action/blob/main/CHANGELOG.md">github/codeql-action's changelog</a>.</em></p>
<blockquote>
<h1>CodeQL Action Changelog</h1>
<p>See the <a href="https://github.com/github/codeql-action/releases">releases page</a> for the relevant changes to the CodeQL CLI and language packs.</p>
<p>Note that the only difference between <code>v2</code> and <code>v3</code> of the CodeQL Action is the node version they support, with <code>v3</code> running on node 20 while we continue to release <code>v2</code> to support running on node 16. For example <code>3.22.11</code> was the first <code>v3</code> release and is functionally identical to <code>2.22.11</code>. This approach ensures an easy way to track exactly which features are included in different versions, indicated by the minor and patch version numbers.</p>
<h2>[UNRELEASED]</h2>
<p>No user facing changes.</p>
<h2>3.24.0 - 02 Feb 2024</h2>
<ul>
<li>CodeQL Python analysis will no longer install dependencies on GitHub Enterprise Server, as is already the case for GitHub.com. See <a href="https://github.com/github/codeql-action/blob/main/#3230---08-jan-2024">release notes for 3.23.0</a> for more details. <a href="https://redirect.github.com/github/codeql-action/pull/2106">#2106</a></li>
</ul>
<h2>3.23.2 - 26 Jan 2024</h2>
<ul>
<li>On Linux, the maximum possible value for the <code>--threads</code> option now respects the CPU count as specified in <code>cgroup</code> files to more accurately reflect the number of available cores when running in containers. <a href="https://redirect.github.com/github/codeql-action/pull/2083">#2083</a></li>
<li>Update default CodeQL bundle version to 2.16.1. <a href="https://redirect.github.com/github/codeql-action/pull/2096">#2096</a></li>
</ul>
<h2>3.23.1 - 17 Jan 2024</h2>
<ul>
<li>Update default CodeQL bundle version to 2.16.0. <a href="https://redirect.github.com/github/codeql-action/pull/2073">#2073</a></li>
<li>Change the retention period for uploaded debug artifacts to 7 days. Previously, this was whatever the repository default was. <a href="https://redirect.github.com/github/codeql-action/pull/2079">#2079</a></li>
</ul>
<h2>3.23.0 - 08 Jan 2024</h2>
<ul>
<li>We are rolling out a feature in January 2024 that will disable Python dependency installation by default for all users. This improves the speed of analysis while having only a very minor impact on results. You can override this behavior by setting <code>CODEQL_ACTION_DISABLE_PYTHON_DEPENDENCY_INSTALLATION=false</code> in your workflow, however we plan to remove this ability in future versions of the CodeQL Action. <a href="https://redirect.github.com/github/codeql-action/pull/2031">#2031</a></li>
<li>The CodeQL Action now requires CodeQL version 2.11.6 or later. For more information, see <a href="https://github.com/github/codeql-action/blob/main/#2227---16-nov-2023">the corresponding changelog entry for CodeQL Action version 2.22.7</a>. <a href="https://redirect.github.com/github/codeql-action/pull/2009">#2009</a></li>
</ul>
<h2>3.22.12 - 22 Dec 2023</h2>
<ul>
<li>Update default CodeQL bundle version to 2.15.5. <a href="https://redirect.github.com/github/codeql-action/pull/2047">#2047</a></li>
</ul>
<h2>3.22.11 - 13 Dec 2023</h2>
<ul>
<li>[v3+ only] The CodeQL Action now runs on Node.js v20. <a href="https://redirect.github.com/github/codeql-action/pull/2006">#2006</a></li>
</ul>
<h2>2.22.10 - 12 Dec 2023</h2>
<ul>
<li>Update default CodeQL bundle version to 2.15.4. <a href="https://redirect.github.com/github/codeql-action/pull/2016">#2016</a></li>
</ul>
<h2>2.22.9 - 07 Dec 2023</h2>
<p>No user facing changes.</p>
<h2>2.22.8 - 23 Nov 2023</h2>
<ul>
<li>Update default CodeQL bundle version to 2.15.3. <a href="https://redirect.github.com/github/codeql-action/pull/2001">#2001</a></li>
</ul>
<h2>2.22.7 - 16 Nov 2023</h2>
</blockquote>
<p>... (truncated)</p>
</details>
<details>
<summary>Commits</summary>
<ul>
<li><a href="e8893c57a1"><code>e8893c5</code></a> Merge pull request <a href="https://redirect.github.com/github/codeql-action/issues/2113">#2113</a> from github/update-v3.24.0-2db032717</li>
<li><a href="78d6c8e84d"><code>78d6c8e</code></a> Update changelog for v3.24.0</li>
<li><a href="2db0327171"><code>2db0327</code></a> Merge pull request <a href="https://redirect.github.com/github/codeql-action/issues/2112">#2112</a> from github/henrymercer/status-report-handle-disk-fa...</li>
<li><a href="f9dea84e29"><code>f9dea84</code></a> Status report: Handle failures determining disk usage</li>
<li><a href="81eb6b2bf4"><code>81eb6b2</code></a> Merge pull request <a href="https://redirect.github.com/github/codeql-action/issues/2108">#2108</a> from github/henrymercer/build-mode-input</li>
<li><a href="483bef1dab"><code>483bef1</code></a> Merge pull request <a href="https://redirect.github.com/github/codeql-action/issues/2106">#2106</a> from github/rasmuswl/default-no-dep-inst</li>
<li><a href="b58c2f67a6"><code>b58c2f6</code></a> Detail requirements for different build modes</li>
<li><a href="f7d53249e3"><code>f7d5324</code></a> Update wording for CHANGELOG.md</li>
<li><a href="254b53d999"><code>254b53d</code></a> Merge branch 'main' into henrymercer/build-mode-input</li>
<li><a href="e34513334c"><code>e345133</code></a> Merge pull request <a href="https://redirect.github.com/github/codeql-action/issues/2107">#2107</a> from github/henrymercer/refactor-config</li>
<li>Additional commits viewable in <a href="b7bf0a3ed3...e8893c57a1">compare view</a></li>
</ul>
</details>
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Add a new `BuildTargets` class that provides commonly used build targets. And avoid importing files from `build_system/targets` except from the top level entrypoints or from top level commands.
Also move `scene_importer.dart` and `shader_compiler.dart` into `build_system/tools` because they are not `Target` classes, but wrapper for certain tools.
With this change, we can ignore all files in `build_system/targets` internally and make PR #142709 easier to land internally. See cl/603434066 for the corresponding internal change.
Related to:
https://github.com/flutter/flutter/pull/142709https://github.com/flutter/flutter/issues/142041
Also note that I have opted to add a new variable in `globals.dart` for `BuildTargets` in this PR, but I know that we are trying to get rid of globals. Several alternatives that I was considering:
1. Add a new field in `BuildSystem` that returns a `BuildTargets` instance. Since `BuildSystem` is already in `globals`, we can access build targets using `globals.buildSystem.buildTargets` without adding a new global variable.
2. Properly inject the `BuildTargetsImpl` instance from the top level `executable.dart` and top level commands.
Let me know if you want me to do one of the above instead. Thanks!
*Replace this paragraph with a description of what this PR is changing or adding, and why. Consider including before/after screenshots.*
*List which issues are fixed by this PR. You must list at least one issue. An issue is not required if the PR fixes something trivial like a typo.*
*If you had to change anything in the [flutter/tests] repo, include a link to the migration guide as per the [breaking change policy].*
This implements dual compile via the newly available flutter.js bootstrapping APIs for intelligent build fallback.
* Users can now use the `FlutterLoader.load` API from flutter.js
* Flutter tool injects build info into the `index.html` of the user so that the bootstrapper knows which build variants are available to bootstrap
* The semantics of the `--wasm` flag for `flutter build web` have changed:
- Instead of producing a separate `build/web_wasm` directory, the output goes to the `build/web` directory like a normal web build
- Produces a dual build that contains two build variants: dart2wasm+skwasm and dart2js+CanvasKit. The dart2wasm+skwasm will only work on Chrome in a cross-origin isolated context, all other environments will fall back to dart2js+CanvasKit.
- `--wasm` and `--web-renderer` are now mutually exclusive. Since there are multiple build variants with `--wasm`, the web renderer cannot be expressed via a single command-line flag. For now, we are hard coding what build variants are produced with the `--wasm` flag, but I plan on making this more customizable in the future.
* Build targets now can optionally provide a "build key" which can uniquely identify any specific parameterization of that build target. This way, the build target can invalidate itself by changing its build key. This works a bit better than just stuffing everything into the environment defines because (a) it doesn't invalidate the entire build, just the targets which are affected and (b) settings for multiple build variants don't translate well to the flat map of environment defines.
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.
Changes to use the proto.textpb config file as the version of the emulator device and show the cipd dependency version in the dependencies so devs know it can be updated.
*List which issues are fixed by this PR. You must list at least one issue. An issue is not required if the PR fixes something trivial like a typo.*
Fixes https://github.com/flutter/flutter/issues/142261
*If you had to change anything in the [flutter/tests] repo, include a link to the migration guide as per the [breaking change policy].*
Context: Follow up from sync with @itsjustkevin today. Tag and ping the actor of workflow, when the cherry pick pull request is successfully created.
1. actor of workflow will be the username of the user that triggered the initial workflow run. i.e., whoever labels the PR. This person might not necessarily be the author of the cherry pick PR.
2. PR number of newly created cherry pick PR is parsed from the output of "gh pr create" as a multi line string.
Tested: on cp success: https://github.com/flutter/flutter/pull/142674 pings the actor of workflow (not the pr author). on cp failure: [example workflow](https://github.com/XilaiZhang/miscellaneous-side-project/actions/runs/7734400373/job/21088324523) leaves a msg on the original PR.
This PR is step 5 in the journey to solve issue #136139 and make the entire Flutter repo more readable.
(previous pull requests: #139048, #139882, #141591, #142279)
The current focus is on `packages/flutter/lib/src/material/`.
The previous PR covered files in this directory starting with `a`, `b`, and `c`; this pull request is for `d` through `m`.
When the Dart VM is not found within 10 minutes in CI on CoreDevices (iOS 17+), stop the app and upload the logs from DerivedData. The app has to be stopped first since the logs are not put in DerivedData until it's stopped.
Also, rearranged some logic to have CoreDevice have its own function for Dart VM url discovery.
Debugging for https://github.com/flutter/flutter/issues/142448.
On the beta branch:
```
Verifying the code signature of /Users/m/Projects/flutter/bin/cache/artifacts/engine/ios-profile/extension_safe/Flutter.xcframework
Verifying the code signature of /Users/m/Projects/flutter/bin/cache/artifacts/engine/ios-profile/Flutter.xcframework
Verifying the code signature of /Users/m/Projects/flutter/bin/cache/artifacts/engine/ios/extension_safe/Flutter.xcframework
Verifying the code signature of /Users/m/Projects/flutter/bin/cache/artifacts/engine/ios/Flutter.xcframework
Verifying the code signature of /Users/m/Projects/flutter/bin/cache/artifacts/engine/ios-release/extension_safe/Flutter.xcframework
Verifying the code signature of /Users/m/Projects/flutter/bin/cache/artifacts/engine/ios-release/Flutter.xcframework
```
Fixes https://github.com/flutter/flutter/issues/140934
This PR improves the gen_defaults tests to not be tied to a particular order of execution.
Since there is a global class that holds the state of the used/not used tokens, we need to clear this logger before each test.
Fixes https://github.com/flutter/flutter/issues/142716
cc @zanderso @QuncCccccc
*If you had to change anything in the [flutter/tests] repo, include a link to the migration guide as per the [breaking change policy].*
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'),
)
```
This PR fixes CupertinoTabView's handling of Android back button with PopScope and nested navigators by calling `NavigatorState.maybePop` instead of `NavigatorState.pop`, so that the Navigator pops only when it should.
Fix#139050
This PR is to add 19 new `ColorScheme` roles following the Material Design 3 specs. This PR doesn't apply the new colors to `ThemeData` or any widgets.
This PR is created to split the big change in #138521, once this is merged, another PR that contains the rest of the changes(apply new color roles to widgets and deprecate 3 more colors) will follow.
**Tone-based surface colors** (7 colors):
* surfaceBright
* surfaceDim
* surfaceContainer
* surfaceContainerLowest
* surfaceContainerLow
* surfaceContainerHigh
* surfaceContainerHighest
**Accent color add-ons** (12 colors):
* primary/secondary/tertiary-Fixed
* primary/secondary/tertiary-FixedDim
* onPrimary/onSecondary/onTertiary-Fixed
* onPrimary/onSecondary/onTertiary-FixedVariant
Please checkout this [design doc](https://docs.google.com/document/d/1ODqivpM_6c490T4j5XIiWCDKo5YqHy78YEFqDm4S8h4/edit?usp=sharing) for more information:)
## Description
This changes the factory constructors for `TextButton.icon`, `ElevatedButton.icon`, `FilledButton.icon`, and `FilledButton.tonalIcon` to take nullable icons. If the icon is null, then the "regular" version of the button is created.
## Tests
- Added tests for all four constructors.
The regular chip and the action chip templates were referencing non existent M3 design tokens.
Fixes https://github.com/flutter/flutter/issues/141288
The `ActionChip` doesn't have any visual difference. Even though the template and file changes, the default `labelStyle` color already uses `onSurface`.
For the reviewer, I've changed the `action_chip_test` to expect a color from the colorScheme so that it is more explicit that the color might not be the same as the labelLarge default in the global textTheme, even if for this case the color is the same.
The regular `Chip` does have visual differences, in particular, the label and trailing icon colors, which were not following the specification. In order to fix this, the regular chip now is based from the `filter-chip` spec as described in the linked issue.
## Before
## After
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'),
)
```
## Description
Fixes a paragraph in the `showDialog` docs that had strange placement due to evolution of the docs. Fixed some missing words too.
## Related Issues
- Fixes https://github.com/flutter/flutter/issues/142097
