FixedExtentMetrics class

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

Constructors

FixedExtentMetrics({required double? minScrollExtent, required double? maxScrollExtent, required double? pixels, required double? viewportDimension, required AxisDirection axisDirection, required int itemIndex, required double devicePixelRatio})
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.
no setterinherited
axis Axis
The axis in which the scroll view scrolls.
no setterinherited
axisDirection AxisDirection
The direction in which the scroll view scrolls.
finalinherited
devicePixelRatio double
The FlutterView.devicePixelRatio of the view that the Scrollable associated with this metrics object is drawn into.
finalinherited
extentAfter double
The quantity of content conceptually "below" the viewport in the scrollable. This is the content below the content described by extentInside.
no setterinherited
extentBefore double
The quantity of content conceptually "above" the viewport in the scrollable. This is the content above the content described by extentInside.
no setterinherited
extentInside double
The quantity of content conceptually "inside" the viewport in the scrollable (including empty space if the total amount of content is less than the viewportDimension).
no setterinherited
extentTotal double
The total quantity of content available.
no setterinherited
hasContentDimensions bool
Whether the minScrollExtent and the maxScrollExtent properties are available.
no setterinherited
hashCode int
The hash code for this object.
no setterinherited
hasPixels bool
Whether the pixels property is available.
no setterinherited
hasViewportDimension bool
Whether the viewportDimension property is available.
no setterinherited
itemIndex int
The scroll view's currently selected item index.
final
maxScrollExtent double
The maximum in-range value for pixels.
no setterinherited
minScrollExtent double
The minimum in-range value for pixels.
no setterinherited
outOfRange bool
Whether the pixels value is outside the minScrollExtent and maxScrollExtent.
no setterinherited
pixels double
The current scroll position, in logical pixels along the axisDirection.
no setterinherited
runtimeType Type
A representation of the runtime type of the object.
no setterinherited
viewportDimension double
The extent of the viewport along the axisDirection.
no setterinherited

Methods

copyWith({double? minScrollExtent, double? maxScrollExtent, double? pixels, double? viewportDimension, AxisDirection? axisDirection, int? itemIndex, double? devicePixelRatio}) FixedExtentMetrics
Creates a ScrollMetrics that has the same properties as this object.
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() String
A string representation of this object.
inherited

Operators

operator ==(Object other) bool
The equality operator.
inherited