GeomReduceCallback<T> typedef

GeomReduceCallback<T> = T? Function(T? previousValue, GeometryType? currentGeometry, int? featureIndex, Map<String, dynamic>? featureProperties, BBox? featureBBox, dynamic featureId)

Callback for geomReduce

The first time the callback function is called, the values provided as arguments depend on whether the reduce method has an initialValue argument.

If an initialValue is provided to the reduce method:

• The previousValue argument is initialValue.
• The currentValue argument is the value of the first element present in the List.

If an initialValue is not provided:

• The previousValue argument is the value of the first element present in the List.
• The currentGeometry argument is the value of the second element present in the List.

Implementation

typedef GeomReduceCallback<T> = T? Function(
  T? previousValue,
  GeometryType? currentGeometry,
  int? featureIndex,
  Map<String, dynamic>? featureProperties,
  BBox? featureBBox,
  dynamic featureId,
);