maxShowOnScreenExtent property Null safety

double maxShowOnScreenExtent

The biggest the floating header can expand to in the main axis direction, in response to a RenderObject.showOnScreen call, in addition to its RenderSliverPersistentHeader.maxExtent.

When a floating persistent header is told to show a Rect on screen, it may expand itself to accommodate the Rect. The maximum extent that is allowed for such expansion is either RenderSliverPersistentHeader.maxExtent or maxShowOnScreenExtent, whichever is smaller. If the persistent header's current extent is already larger than that maximum extent, it will remain unchanged.

This parameter can be set to the persistent header's minExtent (or double.negativeInfinity) so the persistent header will never try to expand when RenderObject.showOnScreen is called on it.

Defaults to double.infinity, must be greater than or equal to minShowOnScreenExtent. Has no effect unless the persistent header is a floating header.


final double maxShowOnScreenExtent;