/
bottom_sheet.dart
1436 lines (1304 loc) · 52.7 KB
/
bottom_sheet.dart
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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flutter/gestures.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/widgets.dart';
import 'bottom_sheet_theme.dart';
import 'color_scheme.dart';
import 'colors.dart';
import 'constants.dart';
import 'curves.dart';
import 'debug.dart';
import 'material.dart';
import 'material_localizations.dart';
import 'material_state.dart';
import 'scaffold.dart';
import 'theme.dart';
const Duration _bottomSheetEnterDuration = Duration(milliseconds: 250);
const Duration _bottomSheetExitDuration = Duration(milliseconds: 200);
const Curve _modalBottomSheetCurve = decelerateEasing;
const double _minFlingVelocity = 700.0;
const double _closeProgressThreshold = 0.5;
const double _defaultScrollControlDisabledMaxHeightRatio = 9.0 / 16.0;
/// A callback for when the user begins dragging the bottom sheet.
///
/// Used by [BottomSheet.onDragStart].
typedef BottomSheetDragStartHandler = void Function(DragStartDetails details);
/// A callback for when the user stops dragging the bottom sheet.
///
/// Used by [BottomSheet.onDragEnd].
typedef BottomSheetDragEndHandler = void Function(
DragEndDetails details, {
required bool isClosing,
});
/// A Material Design bottom sheet.
///
/// There are two kinds of bottom sheets in Material Design:
///
/// * _Persistent_. A persistent bottom sheet shows information that
/// supplements the primary content of the app. A persistent bottom sheet
/// remains visible even when the user interacts with other parts of the app.
/// Persistent bottom sheets can be created and displayed with the
/// [ScaffoldState.showBottomSheet] function or by specifying the
/// [Scaffold.bottomSheet] constructor parameter.
///
/// * _Modal_. A modal bottom sheet is an alternative to a menu or a dialog and
/// prevents the user from interacting with the rest of the app. Modal bottom
/// sheets can be created and displayed with the [showModalBottomSheet]
/// function.
///
/// The [BottomSheet] widget itself is rarely used directly. Instead, prefer to
/// create a persistent bottom sheet with [ScaffoldState.showBottomSheet] or
/// [Scaffold.bottomSheet], and a modal bottom sheet with [showModalBottomSheet].
///
/// See also:
///
/// * [showBottomSheet] and [ScaffoldState.showBottomSheet], for showing
/// non-modal "persistent" bottom sheets.
/// * [showModalBottomSheet], which can be used to display a modal bottom
/// sheet.
/// * [BottomSheetThemeData], which can be used to customize the default
/// bottom sheet property values.
/// * The Material 2 spec at <https://m2.material.io/components/sheets-bottom>.
/// * The Material 3 spec at <https://m3.material.io/components/bottom-sheets/overview>.
class BottomSheet extends StatefulWidget {
/// Creates a bottom sheet.
///
/// Typically, bottom sheets are created implicitly by
/// [ScaffoldState.showBottomSheet], for persistent bottom sheets, or by
/// [showModalBottomSheet], for modal bottom sheets.
const BottomSheet({
super.key,
this.animationController,
this.enableDrag = true,
this.showDragHandle,
this.dragHandleColor,
this.dragHandleSize,
this.onDragStart,
this.onDragEnd,
this.backgroundColor,
this.shadowColor,
this.elevation,
this.shape,
this.clipBehavior,
this.constraints,
required this.onClosing,
required this.builder,
}) : assert(elevation == null || elevation >= 0.0);
/// The animation controller that controls the bottom sheet's entrance and
/// exit animations.
///
/// The BottomSheet widget will manipulate the position of this animation, it
/// is not just a passive observer.
final AnimationController? animationController;
/// Called when the bottom sheet begins to close.
///
/// A bottom sheet might be prevented from closing (e.g., by user
/// interaction) even after this callback is called. For this reason, this
/// callback might be call multiple times for a given bottom sheet.
final VoidCallback onClosing;
/// A builder for the contents of the sheet.
///
/// The bottom sheet will wrap the widget produced by this builder in a
/// [Material] widget.
final WidgetBuilder builder;
/// If true, the bottom sheet can be dragged up and down and dismissed by
/// swiping downwards.
///
/// If [showDragHandle] is true, this only applies to the content below the drag handle,
/// because the drag handle is always draggable.
///
/// Default is true.
///
/// If this is true, the [animationController] must not be null.
/// Use [BottomSheet.createAnimationController] to create one, or provide
/// another AnimationController.
final bool enableDrag;
/// Specifies whether a drag handle is shown.
///
/// The drag handle appears at the top of the bottom sheet. The default color is
/// [ColorScheme.onSurfaceVariant] with an opacity of 0.4 and can be customized
/// using [dragHandleColor]. The default size is `Size(32,4)` and can be customized
/// with [dragHandleSize].
///
/// If null, then the value of [BottomSheetThemeData.showDragHandle] is used. If
/// that is also null, defaults to false.
///
/// If this is true, the [animationController] must not be null.
/// Use [BottomSheet.createAnimationController] to create one, or provide
/// another AnimationController.
final bool? showDragHandle;
/// The bottom sheet drag handle's color.
///
/// Defaults to [BottomSheetThemeData.dragHandleColor].
/// If that is also null, defaults to [ColorScheme.onSurfaceVariant].
final Color? dragHandleColor;
/// Defaults to [BottomSheetThemeData.dragHandleSize].
/// If that is also null, defaults to Size(32, 4).
final Size? dragHandleSize;
/// Called when the user begins dragging the bottom sheet vertically, if
/// [enableDrag] is true.
///
/// Would typically be used to change the bottom sheet animation curve so
/// that it tracks the user's finger accurately.
final BottomSheetDragStartHandler? onDragStart;
/// Called when the user stops dragging the bottom sheet, if [enableDrag]
/// is true.
///
/// Would typically be used to reset the bottom sheet animation curve, so
/// that it animates non-linearly. Called before [onClosing] if the bottom
/// sheet is closing.
final BottomSheetDragEndHandler? onDragEnd;
/// The bottom sheet's background color.
///
/// Defines the bottom sheet's [Material.color].
///
/// Defaults to null and falls back to [Material]'s default.
final Color? backgroundColor;
/// The color of the shadow below the sheet.
///
/// If this property is null, then [BottomSheetThemeData.shadowColor] of
/// [ThemeData.bottomSheetTheme] is used. If that is also null, the default value
/// is transparent.
///
/// See also:
///
/// * [elevation], which defines the size of the shadow below the sheet.
/// * [shape], which defines the shape of the sheet and its shadow.
final Color? shadowColor;
/// The z-coordinate at which to place this material relative to its parent.
///
/// This controls the size of the shadow below the material.
///
/// Defaults to 0. The value is non-negative.
final double? elevation;
/// The shape of the bottom sheet.
///
/// Defines the bottom sheet's [Material.shape].
///
/// Defaults to null and falls back to [Material]'s default.
final ShapeBorder? shape;
/// {@macro flutter.material.Material.clipBehavior}
///
/// Defines the bottom sheet's [Material.clipBehavior].
///
/// Use this property to enable clipping of content when the bottom sheet has
/// a custom [shape] and the content can extend past this shape. For example,
/// a bottom sheet with rounded corners and an edge-to-edge [Image] at the
/// top.
///
/// If this property is null then [BottomSheetThemeData.clipBehavior] of
/// [ThemeData.bottomSheetTheme] is used. If that's null then the behavior
/// will be [Clip.none].
final Clip? clipBehavior;
/// Defines minimum and maximum sizes for a [BottomSheet].
///
/// If null, then the ambient [ThemeData.bottomSheetTheme]'s
/// [BottomSheetThemeData.constraints] will be used. If that
/// is null and [ThemeData.useMaterial3] is true, then the bottom sheet
/// will have a max width of 640dp. If [ThemeData.useMaterial3] is false, then
/// the bottom sheet's size will be constrained by its parent
/// (usually a [Scaffold]). In this case, consider limiting the width by
/// setting smaller constraints for large screens.
///
/// If constraints are specified (either in this property or in the
/// theme), the bottom sheet will be aligned to the bottom-center of
/// the available space. Otherwise, no alignment is applied.
final BoxConstraints? constraints;
@override
State<BottomSheet> createState() => _BottomSheetState();
/// Creates an [AnimationController] suitable for a
/// [BottomSheet.animationController].
///
/// This API available as a convenience for a Material compliant bottom sheet
/// animation. If alternative animation durations are required, a different
/// animation controller could be provided.
static AnimationController createAnimationController(
TickerProvider vsync,
{ AnimationStyle? sheetAnimationStyle }
) {
return AnimationController(
duration: sheetAnimationStyle?.duration ?? _bottomSheetEnterDuration,
reverseDuration: sheetAnimationStyle?.reverseDuration ?? _bottomSheetExitDuration,
debugLabel: 'BottomSheet',
vsync: vsync,
);
}
}
class _BottomSheetState extends State<BottomSheet> {
final GlobalKey _childKey = GlobalKey(debugLabel: 'BottomSheet child');
double get _childHeight {
final RenderBox renderBox = _childKey.currentContext!.findRenderObject()! as RenderBox;
return renderBox.size.height;
}
bool get _dismissUnderway => widget.animationController!.status == AnimationStatus.reverse;
Set<MaterialState> dragHandleMaterialState = <MaterialState>{};
void _handleDragStart(DragStartDetails details) {
setState(() {
dragHandleMaterialState.add(MaterialState.dragged);
});
widget.onDragStart?.call(details);
}
void _handleDragUpdate(DragUpdateDetails details) {
assert(
(widget.enableDrag || (widget.showDragHandle?? false)) && widget.animationController != null,
"'BottomSheet.animationController' cannot be null when 'BottomSheet.enableDrag' or 'BottomSheet.showDragHandle' is true. "
"Use 'BottomSheet.createAnimationController' to create one, or provide another AnimationController.",
);
if (_dismissUnderway) {
return;
}
widget.animationController!.value -= details.primaryDelta! / _childHeight;
}
void _handleDragEnd(DragEndDetails details) {
assert(
(widget.enableDrag || (widget.showDragHandle?? false)) && widget.animationController != null,
"'BottomSheet.animationController' cannot be null when 'BottomSheet.enableDrag' or 'BottomSheet.showDragHandle' is true. "
"Use 'BottomSheet.createAnimationController' to create one, or provide another AnimationController.",
);
if (_dismissUnderway) {
return;
}
setState(() {
dragHandleMaterialState.remove(MaterialState.dragged);
});
bool isClosing = false;
if (details.velocity.pixelsPerSecond.dy > _minFlingVelocity) {
final double flingVelocity = -details.velocity.pixelsPerSecond.dy / _childHeight;
if (widget.animationController!.value > 0.0) {
widget.animationController!.fling(velocity: flingVelocity);
}
if (flingVelocity < 0.0) {
isClosing = true;
}
} else if (widget.animationController!.value < _closeProgressThreshold) {
if (widget.animationController!.value > 0.0) {
widget.animationController!.fling(velocity: -1.0);
}
isClosing = true;
} else {
widget.animationController!.forward();
}
widget.onDragEnd?.call(
details,
isClosing: isClosing,
);
if (isClosing) {
widget.onClosing();
}
}
bool extentChanged(DraggableScrollableNotification notification) {
if (notification.extent == notification.minExtent && notification.shouldCloseOnMinExtent) {
widget.onClosing();
}
return false;
}
void _handleDragHandleHover(bool hovering) {
if (hovering != dragHandleMaterialState.contains(MaterialState.hovered)) {
setState(() {
if (hovering){
dragHandleMaterialState.add(MaterialState.hovered);
}
else{
dragHandleMaterialState.remove(MaterialState.hovered);
}
});
}
}
@override
Widget build(BuildContext context) {
final BottomSheetThemeData bottomSheetTheme = Theme.of(context).bottomSheetTheme;
final bool useMaterial3 = Theme.of(context).useMaterial3;
final BottomSheetThemeData defaults = useMaterial3 ? _BottomSheetDefaultsM3(context) : const BottomSheetThemeData();
final BoxConstraints? constraints = widget.constraints ?? bottomSheetTheme.constraints ?? defaults.constraints;
final Color? color = widget.backgroundColor ?? bottomSheetTheme.backgroundColor ?? defaults.backgroundColor;
final Color? surfaceTintColor = bottomSheetTheme.surfaceTintColor ?? defaults.surfaceTintColor;
final Color? shadowColor = widget.shadowColor ?? bottomSheetTheme.shadowColor ?? defaults.shadowColor;
final double elevation = widget.elevation ?? bottomSheetTheme.elevation ?? defaults.elevation ?? 0;
final ShapeBorder? shape = widget.shape ?? bottomSheetTheme.shape ?? defaults.shape;
final Clip clipBehavior = widget.clipBehavior ?? bottomSheetTheme.clipBehavior ?? Clip.none;
final bool showDragHandle = widget.showDragHandle ?? (widget.enableDrag && (bottomSheetTheme.showDragHandle ?? false));
Widget? dragHandle;
if (showDragHandle){
dragHandle = _DragHandle(
onSemanticsTap: widget.onClosing,
handleHover: _handleDragHandleHover,
materialState: dragHandleMaterialState,
dragHandleColor: widget.dragHandleColor,
dragHandleSize: widget.dragHandleSize,
);
// Only add [_BottomSheetGestureDetector] to the drag handle when the rest of the
// bottom sheet is not draggable. If the whole bottom sheet is draggable,
// no need to add it.
if (!widget.enableDrag) {
dragHandle = _BottomSheetGestureDetector(
onVerticalDragStart: _handleDragStart,
onVerticalDragUpdate: _handleDragUpdate,
onVerticalDragEnd: _handleDragEnd,
child: dragHandle,
);
}
}
Widget bottomSheet = Material(
key: _childKey,
color: color,
elevation: elevation,
surfaceTintColor: surfaceTintColor,
shadowColor: shadowColor,
shape: shape,
clipBehavior: clipBehavior,
child: NotificationListener<DraggableScrollableNotification>(
onNotification: extentChanged,
child: !showDragHandle
? widget.builder(context)
: Stack(
alignment: Alignment.topCenter,
children: <Widget>[
dragHandle!,
Padding(
padding: const EdgeInsets.only(top: kMinInteractiveDimension),
child: widget.builder(context),
),
],
),
),
);
if (constraints != null) {
bottomSheet = Align(
alignment: Alignment.bottomCenter,
heightFactor: 1.0,
child: ConstrainedBox(
constraints: constraints,
child: bottomSheet,
),
);
}
return !widget.enableDrag ? bottomSheet : _BottomSheetGestureDetector(
onVerticalDragStart: _handleDragStart,
onVerticalDragUpdate: _handleDragUpdate,
onVerticalDragEnd: _handleDragEnd,
child: bottomSheet,
);
}
}
// PERSISTENT BOTTOM SHEETS
// See scaffold.dart
typedef _SizeChangeCallback<Size> = void Function(Size size);
class _DragHandle extends StatelessWidget {
const _DragHandle({
required this.onSemanticsTap,
required this.handleHover,
required this.materialState,
this.dragHandleColor,
this.dragHandleSize,
});
final VoidCallback? onSemanticsTap;
final ValueChanged<bool> handleHover;
final Set<MaterialState> materialState;
final Color? dragHandleColor;
final Size? dragHandleSize;
@override
Widget build(BuildContext context) {
final BottomSheetThemeData bottomSheetTheme = Theme.of(context).bottomSheetTheme;
final BottomSheetThemeData m3Defaults = _BottomSheetDefaultsM3(context);
final Size handleSize = dragHandleSize ?? bottomSheetTheme.dragHandleSize ?? m3Defaults.dragHandleSize!;
return MouseRegion(
onEnter: (PointerEnterEvent event) => handleHover(true),
onExit: (PointerExitEvent event) => handleHover(false),
child: Semantics(
label: MaterialLocalizations.of(context).modalBarrierDismissLabel,
container: true,
onTap: onSemanticsTap,
child: SizedBox(
height: kMinInteractiveDimension,
width: kMinInteractiveDimension,
child: Center(
child: Container(
height: handleSize.height,
width: handleSize.width,
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(handleSize.height/2),
color: MaterialStateProperty.resolveAs<Color?>(dragHandleColor, materialState)
?? MaterialStateProperty.resolveAs<Color?>(bottomSheetTheme.dragHandleColor, materialState)
?? m3Defaults.dragHandleColor,
),
),
),
),
),
);
}
}
class _BottomSheetLayoutWithSizeListener extends SingleChildRenderObjectWidget {
const _BottomSheetLayoutWithSizeListener({
required this.onChildSizeChanged,
required this.animationValue,
required this.isScrollControlled,
required this.scrollControlDisabledMaxHeightRatio,
super.child,
});
final _SizeChangeCallback<Size> onChildSizeChanged;
final double animationValue;
final bool isScrollControlled;
final double scrollControlDisabledMaxHeightRatio;
@override
_RenderBottomSheetLayoutWithSizeListener createRenderObject(BuildContext context) {
return _RenderBottomSheetLayoutWithSizeListener(
onChildSizeChanged: onChildSizeChanged,
animationValue: animationValue,
isScrollControlled: isScrollControlled,
scrollControlDisabledMaxHeightRatio: scrollControlDisabledMaxHeightRatio,
);
}
@override
void updateRenderObject(BuildContext context, _RenderBottomSheetLayoutWithSizeListener renderObject) {
renderObject.onChildSizeChanged = onChildSizeChanged;
renderObject.animationValue = animationValue;
renderObject.isScrollControlled = isScrollControlled;
renderObject.scrollControlDisabledMaxHeightRatio = scrollControlDisabledMaxHeightRatio;
}
}
class _RenderBottomSheetLayoutWithSizeListener extends RenderShiftedBox {
_RenderBottomSheetLayoutWithSizeListener({
RenderBox? child,
required _SizeChangeCallback<Size> onChildSizeChanged,
required double animationValue,
required bool isScrollControlled,
required double scrollControlDisabledMaxHeightRatio,
}) : _onChildSizeChanged = onChildSizeChanged,
_animationValue = animationValue,
_isScrollControlled = isScrollControlled,
_scrollControlDisabledMaxHeightRatio = scrollControlDisabledMaxHeightRatio,
super(child);
Size _lastSize = Size.zero;
_SizeChangeCallback<Size> get onChildSizeChanged => _onChildSizeChanged;
_SizeChangeCallback<Size> _onChildSizeChanged;
set onChildSizeChanged(_SizeChangeCallback<Size> newCallback) {
if (_onChildSizeChanged == newCallback) {
return;
}
_onChildSizeChanged = newCallback;
markNeedsLayout();
}
double get animationValue => _animationValue;
double _animationValue;
set animationValue(double newValue) {
if (_animationValue == newValue) {
return;
}
_animationValue = newValue;
markNeedsLayout();
}
bool get isScrollControlled => _isScrollControlled;
bool _isScrollControlled;
set isScrollControlled(bool newValue) {
if (_isScrollControlled == newValue) {
return;
}
_isScrollControlled = newValue;
markNeedsLayout();
}
double get scrollControlDisabledMaxHeightRatio => _scrollControlDisabledMaxHeightRatio;
double _scrollControlDisabledMaxHeightRatio;
set scrollControlDisabledMaxHeightRatio(double newValue) {
if (_scrollControlDisabledMaxHeightRatio == newValue) {
return;
}
_scrollControlDisabledMaxHeightRatio = newValue;
markNeedsLayout();
}
Size _getSize(BoxConstraints constraints) {
return constraints.constrain(constraints.biggest);
}
@override
double computeMinIntrinsicWidth(double height) {
final double width = _getSize(BoxConstraints.tightForFinite(height: height)).width;
if (width.isFinite) {
return width;
}
return 0.0;
}
@override
double computeMaxIntrinsicWidth(double height) {
final double width = _getSize(BoxConstraints.tightForFinite(height: height)).width;
if (width.isFinite) {
return width;
}
return 0.0;
}
@override
double computeMinIntrinsicHeight(double width) {
final double height = _getSize(BoxConstraints.tightForFinite(width: width)).height;
if (height.isFinite) {
return height;
}
return 0.0;
}
@override
double computeMaxIntrinsicHeight(double width) {
final double height = _getSize(BoxConstraints.tightForFinite(width: width)).height;
if (height.isFinite) {
return height;
}
return 0.0;
}
@override
Size computeDryLayout(BoxConstraints constraints) {
return _getSize(constraints);
}
BoxConstraints _getConstraintsForChild(BoxConstraints constraints) {
return BoxConstraints(
minWidth: constraints.maxWidth,
maxWidth: constraints.maxWidth,
maxHeight: isScrollControlled
? constraints.maxHeight
: constraints.maxHeight * scrollControlDisabledMaxHeightRatio,
);
}
Offset _getPositionForChild(Size size, Size childSize) {
return Offset(0.0, size.height - childSize.height * animationValue);
}
@override
void performLayout() {
size = _getSize(constraints);
if (child != null) {
final BoxConstraints childConstraints = _getConstraintsForChild(constraints);
assert(childConstraints.debugAssertIsValid(isAppliedConstraint: true));
child!.layout(childConstraints, parentUsesSize: !childConstraints.isTight);
final BoxParentData childParentData = child!.parentData! as BoxParentData;
childParentData.offset = _getPositionForChild(size, childConstraints.isTight ? childConstraints.smallest : child!.size);
final Size childSize = childConstraints.isTight ? childConstraints.smallest : child!.size;
if (_lastSize != childSize) {
_lastSize = childSize;
_onChildSizeChanged.call(_lastSize);
}
}
}
}
class _ModalBottomSheet<T> extends StatefulWidget {
const _ModalBottomSheet({
super.key,
required this.route,
this.backgroundColor,
this.elevation,
this.shape,
this.clipBehavior,
this.constraints,
this.isScrollControlled = false,
this.scrollControlDisabledMaxHeightRatio = _defaultScrollControlDisabledMaxHeightRatio,
this.enableDrag = true,
this.showDragHandle = false,
});
final ModalBottomSheetRoute<T> route;
final bool isScrollControlled;
final double scrollControlDisabledMaxHeightRatio;
final Color? backgroundColor;
final double? elevation;
final ShapeBorder? shape;
final Clip? clipBehavior;
final BoxConstraints? constraints;
final bool enableDrag;
final bool showDragHandle;
@override
_ModalBottomSheetState<T> createState() => _ModalBottomSheetState<T>();
}
class _ModalBottomSheetState<T> extends State<_ModalBottomSheet<T>> {
ParametricCurve<double> animationCurve = _modalBottomSheetCurve;
String _getRouteLabel(MaterialLocalizations localizations) {
switch (Theme.of(context).platform) {
case TargetPlatform.iOS:
case TargetPlatform.macOS:
return '';
case TargetPlatform.android:
case TargetPlatform.fuchsia:
case TargetPlatform.linux:
case TargetPlatform.windows:
return localizations.dialogLabel;
}
}
EdgeInsets _getNewClipDetails(Size topLayerSize) {
return EdgeInsets.fromLTRB(0, 0, 0, topLayerSize.height);
}
void handleDragStart(DragStartDetails details) {
// Allow the bottom sheet to track the user's finger accurately.
animationCurve = Curves.linear;
}
void handleDragEnd(DragEndDetails details, {bool? isClosing}) {
// Allow the bottom sheet to animate smoothly from its current position.
animationCurve = Split(
widget.route.animation!.value,
endCurve: _modalBottomSheetCurve,
);
}
@override
Widget build(BuildContext context) {
assert(debugCheckHasMediaQuery(context));
assert(debugCheckHasMaterialLocalizations(context));
final MaterialLocalizations localizations = MaterialLocalizations.of(context);
final String routeLabel = _getRouteLabel(localizations);
return AnimatedBuilder(
animation: widget.route.animation!,
child: BottomSheet(
animationController: widget.route._animationController,
onClosing: () {
if (widget.route.isCurrent) {
Navigator.pop(context);
}
},
builder: widget.route.builder,
backgroundColor: widget.backgroundColor,
elevation: widget.elevation,
shape: widget.shape,
clipBehavior: widget.clipBehavior,
constraints: widget.constraints,
enableDrag: widget.enableDrag,
showDragHandle: widget.showDragHandle,
onDragStart: handleDragStart,
onDragEnd: handleDragEnd,
),
builder: (BuildContext context, Widget? child) {
final double animationValue = animationCurve.transform(
widget.route.animation!.value,
);
return Semantics(
scopesRoute: true,
namesRoute: true,
label: routeLabel,
explicitChildNodes: true,
child: ClipRect(
child: _BottomSheetLayoutWithSizeListener(
onChildSizeChanged: (Size size) {
widget.route._didChangeBarrierSemanticsClip(
_getNewClipDetails(size),
);
},
animationValue: animationValue,
isScrollControlled: widget.isScrollControlled,
scrollControlDisabledMaxHeightRatio: widget.scrollControlDisabledMaxHeightRatio,
child: child,
),
),
);
},
);
}
}
/// A route that represents a Material Design modal bottom sheet.
///
/// {@template flutter.material.ModalBottomSheetRoute}
/// A modal bottom sheet is an alternative to a menu or a dialog and prevents
/// the user from interacting with the rest of the app.
///
/// A closely related widget is a persistent bottom sheet, which shows
/// information that supplements the primary content of the app without
/// preventing the user from interacting with the app. Persistent bottom sheets
/// can be created and displayed with the [showBottomSheet] function or the
/// [ScaffoldState.showBottomSheet] method.
///
/// The [isScrollControlled] parameter specifies whether this is a route for
/// a bottom sheet that will utilize [DraggableScrollableSheet]. Consider
/// setting this parameter to true if this bottom sheet has
/// a scrollable child, such as a [ListView] or a [GridView],
/// to have the bottom sheet be draggable.
///
/// The [isDismissible] parameter specifies whether the bottom sheet will be
/// dismissed when user taps on the scrim.
///
/// The [enableDrag] parameter specifies whether the bottom sheet can be
/// dragged up and down and dismissed by swiping downwards.
///
/// The [useSafeArea] parameter specifies whether the sheet will avoid system
/// intrusions on the top, left, and right. If false, no [SafeArea] is added;
/// and [MediaQuery.removePadding] is applied to the top,
/// so that system intrusions at the top will not be avoided by a [SafeArea]
/// inside the bottom sheet either.
/// Defaults to false.
///
/// The optional [backgroundColor], [elevation], [shape], [clipBehavior],
/// [constraints] and [transitionAnimationController]
/// parameters can be passed in to customize the appearance and behavior of
/// modal bottom sheets (see the documentation for these on [BottomSheet]
/// for more details).
///
/// The [transitionAnimationController] controls the bottom sheet's entrance and
/// exit animations. It's up to the owner of the controller to call
/// [AnimationController.dispose] when the controller is no longer needed.
///
/// The optional `settings` parameter sets the [RouteSettings] of the modal bottom sheet
/// sheet. This is particularly useful in the case that a user wants to observe
/// [PopupRoute]s within a [NavigatorObserver].
/// {@endtemplate}
///
/// {@macro flutter.widgets.RawDialogRoute}
///
/// See also:
///
/// * [showModalBottomSheet], which is a way to display a ModalBottomSheetRoute.
/// * [BottomSheet], which becomes the parent of the widget returned by the
/// function passed as the `builder` argument to [showModalBottomSheet].
/// * [showBottomSheet] and [ScaffoldState.showBottomSheet], for showing
/// non-modal bottom sheets.
/// * [DraggableScrollableSheet], creates a bottom sheet that grows
/// and then becomes scrollable once it reaches its maximum size.
/// * [DisplayFeatureSubScreen], which documents the specifics of how
/// [DisplayFeature]s can split the screen into sub-screens.
/// * The Material 2 spec at <https://m2.material.io/components/sheets-bottom>.
/// * The Material 3 spec at <https://m3.material.io/components/bottom-sheets/overview>.
class ModalBottomSheetRoute<T> extends PopupRoute<T> {
/// A modal bottom sheet route.
ModalBottomSheetRoute({
required this.builder,
this.capturedThemes,
this.barrierLabel,
this.barrierOnTapHint,
this.backgroundColor,
this.elevation,
this.shape,
this.clipBehavior,
this.constraints,
this.modalBarrierColor,
this.isDismissible = true,
this.enableDrag = true,
this.showDragHandle,
required this.isScrollControlled,
this.scrollControlDisabledMaxHeightRatio = _defaultScrollControlDisabledMaxHeightRatio,
super.settings,
this.transitionAnimationController,
this.anchorPoint,
this.useSafeArea = false,
this.sheetAnimationStyle,
});
/// A builder for the contents of the sheet.
///
/// The bottom sheet will wrap the widget produced by this builder in a
/// [Material] widget.
final WidgetBuilder builder;
/// Stores a list of captured [InheritedTheme]s that are wrapped around the
/// bottom sheet.
///
/// Consider setting this attribute when the [ModalBottomSheetRoute]
/// is created through [Navigator.push] and its friends.
final CapturedThemes? capturedThemes;
/// Specifies whether this is a route for a bottom sheet that will utilize
/// [DraggableScrollableSheet].
///
/// Consider setting this parameter to true if this bottom sheet has
/// a scrollable child, such as a [ListView] or a [GridView],
/// to have the bottom sheet be draggable.
final bool isScrollControlled;
/// The max height constraint ratio for the bottom sheet
/// when [isScrollControlled] set to false,
/// no ratio will be applied when [isScrollControlled] set to true.
///
/// Defaults to 9 / 16.
final double scrollControlDisabledMaxHeightRatio;
/// The bottom sheet's background color.
///
/// Defines the bottom sheet's [Material.color].
///
/// If this property is not provided, it falls back to [Material]'s default.
final Color? backgroundColor;
/// The z-coordinate at which to place this material relative to its parent.
///
/// This controls the size of the shadow below the material.
///
/// Defaults to 0, must not be negative.
final double? elevation;
/// The shape of the bottom sheet.
///
/// Defines the bottom sheet's [Material.shape].
///
/// If this property is not provided, it falls back to [Material]'s default.
final ShapeBorder? shape;
/// {@macro flutter.material.Material.clipBehavior}
///
/// Defines the bottom sheet's [Material.clipBehavior].
///
/// Use this property to enable clipping of content when the bottom sheet has
/// a custom [shape] and the content can extend past this shape. For example,
/// a bottom sheet with rounded corners and an edge-to-edge [Image] at the
/// top.
///
/// If this property is null, the [BottomSheetThemeData.clipBehavior] of
/// [ThemeData.bottomSheetTheme] is used. If that's null, the behavior defaults to [Clip.none]
/// will be [Clip.none].
final Clip? clipBehavior;
/// Defines minimum and maximum sizes for a [BottomSheet].
///
/// If null, the ambient [ThemeData.bottomSheetTheme]'s
/// [BottomSheetThemeData.constraints] will be used. If that
/// is null and [ThemeData.useMaterial3] is true, then the bottom sheet
/// will have a max width of 640dp. If [ThemeData.useMaterial3] is false, then
/// the bottom sheet's size will be constrained by its parent
/// (usually a [Scaffold]). In this case, consider limiting the width by
/// setting smaller constraints for large screens.
///
/// If constraints are specified (either in this property or in the
/// theme), the bottom sheet will be aligned to the bottom-center of
/// the available space. Otherwise, no alignment is applied.
final BoxConstraints? constraints;
/// Specifies the color of the modal barrier that darkens everything below the
/// bottom sheet.
///
/// Defaults to `Colors.black54` if not provided.
final Color? modalBarrierColor;
/// Specifies whether the bottom sheet will be dismissed
/// when user taps on the scrim.
///
/// If true, the bottom sheet will be dismissed when user taps on the scrim.
///
/// Defaults to true.
final bool isDismissible;
/// Specifies whether the bottom sheet can be dragged up and down
/// and dismissed by swiping downwards.
///
/// If true, the bottom sheet can be dragged up and down and dismissed by
/// swiping downwards.
///
/// This applies to the content below the drag handle, if showDragHandle is true.
///
/// Defaults is true.
final bool enableDrag;
/// Specifies whether a drag handle is shown.
///
/// The drag handle appears at the top of the bottom sheet. The default color is
/// [ColorScheme.onSurfaceVariant] with an opacity of 0.4 and can be customized
/// using dragHandleColor. The default size is `Size(32,4)` and can be customized
/// with dragHandleSize.
///
/// If null, then the value of [BottomSheetThemeData.showDragHandle] is used. If
/// that is also null, defaults to false.
final bool? showDragHandle;
/// The animation controller that controls the bottom sheet's entrance and
/// exit animations.
///
/// The BottomSheet widget will manipulate the position of this animation, it
/// is not just a passive observer.
final AnimationController? transitionAnimationController;
/// {@macro flutter.widgets.DisplayFeatureSubScreen.anchorPoint}
final Offset? anchorPoint;
/// Whether to avoid system intrusions on the top, left, and right.
///
/// If true, a [SafeArea] is inserted to keep the bottom sheet away from
/// system intrusions at the top, left, and right sides of the screen.
///
/// If false, the bottom sheet will extend through any system intrusions
/// at the top, left, and right.
///
/// If false, then moreover [MediaQuery.removePadding] will be used
/// to remove top padding, so that a [SafeArea] widget inside the bottom
/// sheet will have no effect at the top edge. If this is undesired, consider
/// setting [useSafeArea] to true. Alternatively, wrap the [SafeArea] in a
/// [MediaQuery] that restates an ambient [MediaQueryData] from outside [builder].
///
/// In either case, the bottom sheet extends all the way to the bottom of
/// the screen, including any system intrusions.
///
/// The default is false.
final bool useSafeArea;
/// Used to override the modal bottom sheet animation duration and reverse
/// animation duration.