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OnScrollEvent class has the following properties:

  • event_type (str) - type of the scroll event:
    • start - control has started scrolling;
    • update - control has changed its scroll position;
    • end - control has stopped scrolling;
    • user - user has changed the direction in which they are scrolling;
    • over - control has not changed its scroll position because the change would have caused its scroll position to go outside its scroll bounds;
  • pixels (float) - The current scroll position, in logical pixels.
  • min_scroll_extent (float) - The minimum in-range value for pixels.
  • max_scroll_extent (float) - The maximum in-range value for pixels.
  • viewport_dimension (float) - The extent of the viewport.
  • scroll_delta (float) - The distance by which the scrollable was scrolled, in logical pixels. Set for update events only.
  • direction (str) - The direction in which the user is scrolling: idle, forward, reverse. Set for user events only.
  • overscroll (float) - The number of logical pixels that the scrollable avoided scrolling. Set for over events only.
  • velocity (float) - The velocity at which the ScrollPosition was changing when this overscroll happened. Set for over events only.