FdcGridRangeSelectionOverlayBuilder typedef

FdcGridRangeSelectionOverlayBuilder = Widget Function(BuildContext context, FdcGridRangeSelectionOverlayContext overlayContext)

Builds the visual overlay for an attached range-selection session.

Extension packages implement this callback and the grid host calls it during overlay composition. overlayContext is an immutable geometry snapshot using grid viewport and source-column coordinates. Implementations should render only the overlay and must not mutate selection state. Return SizedBox.shrink() when no visual output is required. Exceptions propagate through the widget build.

This typedef is part of the stable fdc_ext.dart extension seam.

Implementation

typedef FdcGridRangeSelectionOverlayBuilder =
    Widget Function(
      BuildContext context,
      FdcGridRangeSelectionOverlayContext overlayContext,
    );