public CustomScrollView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
Key center = null,
float anchor = 0.0f,
float?cacheExtent = null,
List <Widget> slivers = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
center: center,
anchor: anchor,
cacheExtent: cacheExtent,
dragStartBehavior: dragStartBehavior
)
{
this.slivers = slivers ?? new List <Widget>();
}
public static GridView builder(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
SliverGridDelegate gridDelegate = null,
IndexedWidgetBuilder itemBuilder = null,
int?itemCount = null,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
float?cacheExtent = null
)
{
return(new GridView(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
gridDelegate: gridDelegate,
itemBuilder: itemBuilder,
itemCount: itemCount,
addAutomaticKeepAlives: addAutomaticKeepAlives,
addRepaintBoundaries: addRepaintBoundaries,
cacheExtent: cacheExtent
));
}
protected ScrollView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
float?cacheExtent = null
) : base(key: key)
{
D.assert(!(controller != null && primary == true),
"Primary ScrollViews obtain their ScrollController via inheritance from a PrimaryScrollController widget. " +
"You cannot both set primary to true and pass an explicit controller.");
primary = primary ?? controller == null && scrollDirection == Axis.vertical;
physics = physics ?? (primary.Value ? new AlwaysScrollableScrollPhysics() : null);
this.scrollDirection = scrollDirection;
this.reverse = reverse;
this.controller = controller;
this.primary = primary.Value;
this.physics = physics;
this.shrinkWrap = shrinkWrap;
this.cacheExtent = cacheExtent;
}
protected ScrollView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
Key center = null,
float anchor = 0.0f,
float?cacheExtent = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(key: key)
{
D.assert(!(controller != null && primary == true),
() => "Primary ScrollViews obtain their ScrollController via inheritance from a PrimaryScrollController widget. " +
"You cannot both set primary to true and pass an explicit controller.");
D.assert(!shrinkWrap || center == null);
D.assert(anchor >= 0.0f && anchor <= 1.0f);
primary = primary ?? controller == null && scrollDirection == Axis.vertical;
physics = physics ?? (primary.Value ? new AlwaysScrollableScrollPhysics() : null);
this.scrollDirection = scrollDirection;
this.reverse = reverse;
this.controller = controller;
this.primary = primary.Value;
this.physics = physics;
this.shrinkWrap = shrinkWrap;
this.center = center;
this.anchor = anchor;
this.cacheExtent = cacheExtent;
this.dragStartBehavior = dragStartBehavior;
}
public GridView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
SliverGridDelegate gridDelegate = null,
SliverChildDelegate childrenDelegate = null,
float?cacheExtent = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
cacheExtent: cacheExtent,
dragStartBehavior: dragStartBehavior
)
{
D.assert(gridDelegate != null);
D.assert(childrenDelegate != null);
this.gridDelegate = gridDelegate;
this.childrenDelegate = childrenDelegate;
}
public SingleChildScrollView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
EdgeInsets padding = null,
bool?primary = null,
ScrollPhysics physics = null,
ScrollController controller = null,
Widget child = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(key: key)
{
D.assert(!(controller != null && primary == true),
() =>
"Primary ScrollViews obtain their ScrollController via inheritance from a PrimaryScrollController widget. " +
"You cannot both set primary to true and pass an explicit controller.");
this.scrollDirection = scrollDirection;
this.reverse = reverse;
this.padding = padding;
this.primary = primary ?? controller == null && scrollDirection == Axis.vertical;
this.physics = physics;
this.controller = controller;
this.child = child;
this.dragStartBehavior = dragStartBehavior;
}
public override Widget build(BuildContext context)
{
AxisDirection axisDirection = this._getDirection(context);
Widget contents = this.child;
if (this.padding != null)
{
contents = new Padding(
padding: this.padding,
child: contents);
}
ScrollController scrollController = this.primary
? PrimaryScrollController.of(context)
: this.controller;
Scrollable scrollable = new Scrollable(
axisDirection: axisDirection,
controller: scrollController,
physics: this.physics,
viewportBuilder: (BuildContext subContext, ViewportOffset offset) => {
return(new _SingleChildViewport(
axisDirection: axisDirection,
offset: offset,
child: contents));
}
);
if (this.primary && scrollController != null)
{
return(PrimaryScrollController.none(child: scrollable));
}
return(scrollable);
}
public static GridView custom(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
SliverGridDelegate gridDelegate = null,
SliverChildDelegate childrenDelegate = null,
float?cacheExtent = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
)
{
return(new GridView(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
gridDelegate: gridDelegate,
childrenDelegate: childrenDelegate,
cacheExtent: cacheExtent,
dragStartBehavior: dragStartBehavior
));
}
void _updatePosition()
{
this._configuration = ScrollConfiguration.of(this.context);
this._physics = this._configuration.getScrollPhysics(this.context);
if (this.widget.physics != null)
{
this._physics = this.widget.physics.applyTo(this._physics);
}
ScrollController controller = this.widget.controller;
ScrollPosition oldPosition = this.position;
if (oldPosition != null)
{
if (controller != null)
{
controller.detach(oldPosition);
}
Window.instance.scheduleMicrotask(oldPosition.dispose);
}
this._position = controller == null
? null
: controller.createScrollPosition(this._physics, this, oldPosition);
this._position = this._position
?? new ScrollPositionWithSingleContext(physics: this._physics, context: this,
oldPosition: oldPosition);
D.assert(this.position != null);
if (controller != null)
{
controller.attach(this.position);
}
}
public static ListWheelScrollView useDelegate(
float itemExtent,
List <Widget> children = null,
ListWheelChildDelegate childDelegate = null,
Key key = null,
ScrollController controller = null,
ScrollPhysics physics = null,
float diameterRatio = RenderListWheelViewport.defaultDiameterRatio,
float perspective = RenderListWheelViewport.defaultPerspective,
float offAxisFraction = 0.0f,
bool useMagnifier = false,
float magnification = 1.0f,
ValueChanged <int> onSelectedItemChanged = null,
bool clipToSize = true,
bool renderChildrenOutsideViewport = false
)
{
return(new ListWheelScrollView(
itemExtent: itemExtent,
children: children,
childDelegate: childDelegate,
key: key,
controller: controller,
physics: physics,
diameterRatio: diameterRatio,
perspective: perspective,
offAxisFraction: offAxisFraction,
useMagnifier: useMagnifier,
magnification: magnification,
onSelectedItemChanged: onSelectedItemChanged,
clipToSize: clipToSize,
renderChildrenOutsideViewport: renderChildrenOutsideViewport
));
}
public ListView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
float?itemExtent = null,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
float?cacheExtent = null,
List <Widget> children = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
cacheExtent: cacheExtent,
dragStartBehavior: dragStartBehavior
)
{
this.itemExtent = itemExtent;
this.childrenDelegate = new SliverChildListDelegate(
children,
addAutomaticKeepAlives: addAutomaticKeepAlives,
addRepaintBoundaries: addRepaintBoundaries
);
}
public BoxScrollView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
float?cacheExtent = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
cacheExtent: cacheExtent,
dragStartBehavior: dragStartBehavior
)
{
this.padding = padding;
}
ListView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
float?itemExtent = null,
SliverChildDelegate childrenDelegate = null,
float?cacheExtent = null
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
cacheExtent: cacheExtent
)
{
D.assert(childrenDelegate != null);
this.itemExtent = itemExtent;
this.childrenDelegate = childrenDelegate;
}
public GridView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
SliverGridDelegate gridDelegate = null,
IndexedWidgetBuilder itemBuilder = null,
int?itemCount = null,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
float?cacheExtent = null
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
cacheExtent: cacheExtent
)
{
this.gridDelegate = gridDelegate;
this.childrenDelegate = new SliverChildBuilderDelegate(
itemBuilder,
childCount: itemCount,
addAutomaticKeepAlives: addAutomaticKeepAlives,
addRepaintBoundaries: addRepaintBoundaries
);
}
public GridView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
SliverGridDelegate gridDelegate = null,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
float?cacheExtent = null,
List <Widget> children = null
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
cacheExtent: cacheExtent
)
{
D.assert(gridDelegate != null);
this.childrenDelegate = new SliverChildListDelegate(
children ?? new List <Widget>(),
addAutomaticKeepAlives: addAutomaticKeepAlives,
addRepaintBoundaries: addRepaintBoundaries
);
}
public static ListView custom(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
float?itemExtent = null,
SliverChildDelegate childrenDelegate = null,
float?cacheExtent = null
)
{
return(new ListView(
key,
scrollDirection,
reverse,
controller,
primary,
physics,
shrinkWrap,
padding,
itemExtent,
childrenDelegate,
cacheExtent));
}
public static ListView seperated(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
IndexedWidgetBuilder itemBuilder = null,
IndexedWidgetBuilder separatorBuilder = null,
int itemCount = 0,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
float?cacheExtent = null
)
{
return(new ListView(
key,
scrollDirection,
reverse,
controller,
primary,
physics,
shrinkWrap,
padding,
itemBuilder,
separatorBuilder,
itemCount,
addAutomaticKeepAlives,
addRepaintBoundaries,
cacheExtent
));
}
public override void initState()
{
base.initState();
this.scrollController = this.widget.controller ?? new FixedExtentScrollController();
if (this.widget.controller is FixedExtentScrollController controller)
{
this._lastReportedItemIndex = controller.initialItem;
}
}
public PrimaryScrollController(
Key key = null,
ScrollController controller = null,
Widget child = null
) : base(key: key, child: child)
{
D.assert(controller != null);
this.controller = controller;
}
public override void didUpdateWidget(StatefulWidget oldWidget)
{
base.didUpdateWidget(oldWidget: oldWidget);
if (widget.controller != null && widget.controller != scrollController)
{
var oldScrollController = scrollController;
SchedulerBinding.instance.addPostFrameCallback(_ => { oldScrollController.dispose(); });
scrollController = widget.controller;
}
}
public override void didUpdateWidget(StatefulWidget oldWidget)
{
base.didUpdateWidget(oldWidget);
if (this.widget.controller != null && this.widget.controller != this.scrollController)
{
ScrollController oldScrollController = this.scrollController;
SchedulerBinding.instance.addPostFrameCallback((_) => { oldScrollController.dispose(); });
this.scrollController = this.widget.controller;
}
}
public Scrollable(
Key key = null,
AxisDirection axisDirection = AxisDirection.down,
ScrollController controller = null,
ScrollPhysics physics = null,
ViewportBuilder viewportBuilder = null
) : base(key: key)
{
D.assert(viewportBuilder != null);
this.axisDirection = axisDirection;
this.controller = controller;
this.physics = physics;
this.viewportBuilder = viewportBuilder;
}
public ListWheelScrollView(
float itemExtent,
Key key = null,
ScrollController controller = null,
ScrollPhysics physics = null,
float diameterRatio = RenderListWheelViewport.defaultDiameterRatio,
float perspective = RenderListWheelViewport.defaultPerspective,
float offAxisFraction = 0.0f,
bool useMagnifier = false,
float magnification = 1.0f,
float squeeze = 1.0f,
ValueChanged <int> onSelectedItemChanged = null,
float overAndUnderCenterOpacity = 1.0f,
bool clipToSize = true,
bool renderChildrenOutsideViewport = false,
ListWheelChildDelegate childDelegate = null
) : base(key: key)
{
D.assert(childDelegate != null);
D.assert(diameterRatio > 0.0, () => RenderListWheelViewport.diameterRatioZeroMessage);
D.assert(perspective > 0);
D.assert(perspective <= 0.01, () => RenderListWheelViewport.perspectiveTooHighMessage);
D.assert(magnification > 0);
D.assert(overAndUnderCenterOpacity >= 0 && overAndUnderCenterOpacity <= 1);
D.assert(itemExtent != null);
D.assert(itemExtent > 0);
D.assert(squeeze > 0);
D.assert(
!renderChildrenOutsideViewport || !clipToSize, () =>
RenderListWheelViewport.clipToSizeAndRenderChildrenOutsideViewportConflict
);
this.controller = controller;
this.physics = physics;
this.diameterRatio = diameterRatio;
this.perspective = perspective;
this.offAxisFraction = offAxisFraction;
this.useMagnifier = useMagnifier;
this.magnification = magnification;
this.overAndUnderCenterOpacity = overAndUnderCenterOpacity;
this.itemExtent = itemExtent;
this.squeeze = squeeze;
this.onSelectedItemChanged = onSelectedItemChanged;
this.clipToSize = clipToSize;
this.renderChildrenOutsideViewport = renderChildrenOutsideViewport;
this.childDelegate = childDelegate;
}
public _FixedExtentScrollable(
float itemExtent,
ViewportBuilder viewportBuilder,
Key key = null,
AxisDirection axisDirection = AxisDirection.down,
ScrollController controller = null,
ScrollPhysics physics = null
) : base(
key: key,
axisDirection: axisDirection,
controller: controller,
physics: physics,
viewportBuilder: viewportBuilder
)
{
this.itemExtent = itemExtent;
}
ListView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
IndexedWidgetBuilder itemBuilder = null,
IndexedWidgetBuilder separatorBuilder = null,
int itemCount = 0,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
float?cacheExtent = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
cacheExtent: cacheExtent,
dragStartBehavior: dragStartBehavior
)
{
D.assert(itemBuilder != null);
D.assert(separatorBuilder != null);
D.assert(itemCount >= 0);
this.itemExtent = null;
this.childrenDelegate = new SliverChildBuilderDelegate(
(context, index) => {
int itemIndex = index / 2;
return(index % 2 == 0
? itemBuilder(context, itemIndex)
: separatorBuilder(context, itemIndex));
},
childCount: Mathf.Max(0, itemCount * 2 - 1),
addAutomaticKeepAlives: addAutomaticKeepAlives,
addRepaintBoundaries: addRepaintBoundaries
);
}
public override Widget build(BuildContext context)
{
List <Widget> slivers = this.buildSlivers(context);
AxisDirection axisDirection = this.getDirection(context);
ScrollController scrollController = this.primary ? PrimaryScrollController.of(context) : this.controller;
Scrollable scrollable = new Scrollable(
axisDirection: axisDirection,
controller: scrollController,
physics: this.physics,
viewportBuilder: (viewportContext, offset) =>
this.buildViewport(viewportContext, offset, axisDirection, slivers)
);
return(this.primary && scrollController != null
? (Widget)PrimaryScrollController.none(child: scrollable)
: scrollable);
}
public GridView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
float?maxCrossAxisExtent = null,
float mainAxisSpacing = 0.0f,
float crossAxisSpacing = 0.0f,
float childAspectRatio = 1.0f,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
bool addSemanticIndexes = true,
List <Widget> children = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
dragStartBehavior: dragStartBehavior
)
{
this.gridDelegate = new SliverGridDelegateWithMaxCrossAxisExtent(
maxCrossAxisExtent: maxCrossAxisExtent ?? 0,
mainAxisSpacing: mainAxisSpacing,
crossAxisSpacing: crossAxisSpacing,
childAspectRatio: childAspectRatio
);
this.childrenDelegate = new SliverChildListDelegate(
children ?? new List <Widget> {
},
addAutomaticKeepAlives: addAutomaticKeepAlives,
addRepaintBoundaries: addRepaintBoundaries
);
}
public Scrollable(
Key key = null,
AxisDirection?axisDirection = AxisDirection.down,
ScrollController controller = null,
ScrollPhysics physics = null,
ViewportBuilder viewportBuilder = null,
ScrollIncrementCalculator incrementCalculator = null,
DragStartBehavior dragStartBehavior = DragStartBehavior.start
) : base(key: key)
{
D.assert(axisDirection != null);
D.assert(viewportBuilder != null);
this.axisDirection = axisDirection.Value;
this.controller = controller;
this.physics = physics;
this.viewportBuilder = viewportBuilder;
this.incrementCalculator = incrementCalculator;
this.dragStartBehavior = dragStartBehavior;
}
public GridView(
Key key = null,
Axis scrollDirection = Axis.vertical,
bool reverse = false,
ScrollController controller = null,
bool?primary = null,
ScrollPhysics physics = null,
bool shrinkWrap = false,
EdgeInsets padding = null,
int?crossAxisCount = null,
float mainAxisSpacing = 0.0f,
float crossAxisSpacing = 0.0f,
float childAspectRatio = 1.0f,
bool addAutomaticKeepAlives = true,
bool addRepaintBoundaries = true,
float?cacheExtent = null,
List <Widget> children = null
) : base(
key: key,
scrollDirection: scrollDirection,
reverse: reverse,
controller: controller,
primary: primary,
physics: physics,
shrinkWrap: shrinkWrap,
padding: padding,
cacheExtent: cacheExtent
)
{
this.gridDelegate = new SliverGridDelegateWithFixedCrossAxisCount(
crossAxisCount: crossAxisCount ?? 0,
mainAxisSpacing: mainAxisSpacing,
crossAxisSpacing: crossAxisSpacing,
childAspectRatio: childAspectRatio
);
this.childrenDelegate = new SliverChildListDelegate(
children ?? new List <Widget>(),
addAutomaticKeepAlives: addAutomaticKeepAlives,
addRepaintBoundaries: addRepaintBoundaries
);
}
void _updatePosition()
{
_configuration = ScrollConfiguration.of(context);
_physics = _configuration.getScrollPhysics(context);
if (widget.physics != null)
{
_physics = widget.physics.applyTo(_physics);
}
ScrollController controller = widget.controller;
ScrollPosition oldPosition = position;
if (oldPosition != null)
{
if (controller != null)
{
controller.detach(oldPosition);
}
async_.scheduleMicrotask(() => {
oldPosition.dispose();
return(null);
});
}
if (controller == null)
{
_position = new ScrollPositionWithSingleContext(physics: _physics, context: this, oldPosition: oldPosition);
}
else
{
_position = controller?.createScrollPosition(_physics, this, oldPosition)
?? new ScrollPositionWithSingleContext(physics: _physics, context: this, oldPosition: oldPosition);
}
D.assert(position != null);
if (controller != null)
{
controller.attach(position);
}
}
