ScaleUpdateDetails constructor Null safety

ScaleUpdateDetails(
  1. {Offset focalPoint = Offset.zero,
  2. Offset? localFocalPoint,
  3. double scale = 1.0,
  4. double horizontalScale = 1.0,
  5. double verticalScale = 1.0,
  6. double rotation = 0.0,
  7. int pointerCount = 0,
  8. Offset focalPointDelta = Offset.zero}
)

Creates details for GestureScaleUpdateCallback.

The focalPoint, scale, horizontalScale, verticalScale, rotation arguments must not be null. The scale, horizontalScale, and verticalScale argument must be greater than or equal to zero.

Implementation

ScaleUpdateDetails({
  this.focalPoint = Offset.zero,
  Offset? localFocalPoint,
  this.scale = 1.0,
  this.horizontalScale = 1.0,
  this.verticalScale = 1.0,
  this.rotation = 0.0,
  this.pointerCount = 0,
  this.focalPointDelta = Offset.zero,
}) : assert(focalPoint != null),
     assert(focalPointDelta != null),
     assert(scale != null && scale >= 0.0),
     assert(horizontalScale != null && horizontalScale >= 0.0),
     assert(verticalScale != null && verticalScale >= 0.0),
     assert(rotation != null),
     localFocalPoint = localFocalPoint ?? focalPoint;