FixedExtentMetrics class Null safety
Metrics for a ScrollPosition to a scroll view with fixed item sizes.
The metrics are available on ScrollNotifications generated from a scroll views such as ListWheelScrollViews with a FixedExtentScrollController and exposes the current itemIndex and the scroll view's extents.
FixedExtent refers to the fact that the scrollable items have the same
size. This is distinct from Fixed in the parent class name's
FixedScrollMetrics which refers to its immutability.
- Inheritance
-
- Object
- FixedScrollMetrics
- FixedExtentMetrics
Constructors
- FixedExtentMetrics({required double? minScrollExtent, required double? maxScrollExtent, required double? pixels, required double? viewportDimension, required AxisDirection axisDirection, required int itemIndex})
- Creates an immutable snapshot of values associated with a ListWheelScrollView.
Properties
- atEdge → bool
-
Whether the pixels value is exactly at the minScrollExtent or the
maxScrollExtent.
read-onlyinherited
- axis → Axis
-
The axis in which the scroll view scrolls.
read-onlyinherited
- axisDirection → AxisDirection
-
The direction in which the scroll view scrolls.
finalinherited
- extentAfter → double
-
The quantity of content conceptually "below" the viewport in the scrollable.
This is the content below the content described by extentInside.
read-onlyinherited
- extentBefore → double
-
The quantity of content conceptually "above" the viewport in the scrollable.
This is the content above the content described by extentInside.
read-onlyinherited
- extentInside → double
-
The quantity of content conceptually "inside" the viewport in the scrollable.
read-onlyinherited
- hasContentDimensions → bool
-
Whether the minScrollExtent and the maxScrollExtent properties are available.
read-onlyinherited
- hashCode → int
-
The hash code for this object.
read-onlyinherited
- hasPixels → bool
-
Whether the pixels property is available.
read-onlyinherited
- hasViewportDimension → bool
-
Whether the viewportDimension property is available.
read-onlyinherited
- itemIndex → int
-
The scroll view's currently selected item index.
final
- maxScrollExtent → double
-
The maximum in-range value for pixels.
read-onlyinherited
- minScrollExtent → double
-
The minimum in-range value for pixels.
read-onlyinherited
- outOfRange → bool
-
Whether the pixels value is outside the minScrollExtent and
maxScrollExtent.
read-onlyinherited
- pixels → double
-
The current scroll position, in logical pixels along the axisDirection.
read-onlyinherited
- runtimeType → Type
-
A representation of the runtime type of the object.
read-onlyinherited
- viewportDimension → double
-
The extent of the viewport along the axisDirection.
read-onlyinherited
Methods
-
copyWith(
{double? minScrollExtent, double? maxScrollExtent, double? pixels, double? viewportDimension, AxisDirection? axisDirection, int? itemIndex}) → FixedExtentMetrics -
Creates a ScrollMetrics that has the same properties as this object.
override
-
noSuchMethod(
Invocation invocation) → dynamic -
Invoked when a non-existent method or property is accessed.
inherited
-
toString(
) → String -
A string representation of this object.
inherited
Operators
-
operator ==(
Object other) → bool -
The equality operator.
inherited