topEdgeFadeExtent property
Extra fade height beyond the auto-calculated app bar area.
The total top fade height = safe area top + appBarHeight + topEdgeFadeExtent. Defaults to 20.0.
Negative values (e.g. -20.0) are valid and retract the fade boundary
inside the app bar area — especially useful with GlassScrollEdgeStyle.blur
to keep content sharp until it passes directly beneath the bar.
Implementation
final double topEdgeFadeExtent;