EventControllerScroll is an event controller meant to handle scroll events from mice and touchpads.
It is capable of handling both discrete and continuous scroll events, abstracting them both on the scroll signal (deltas in the discrete case are multiples of 1).
The behavior of the event controller can be modified by the flags given at creation time, or modified at a later point through set_flags (e.g. because the scrolling conditions of the widget changed).
The controller can be set up to emit motion for either/both vertical and horizontal scroll events through
. If any axis is disabled, the respective scroll delta will
be 0. Vertical scroll events will be translated to horizontal motion for the devices incapable of horizontal scrolling.
The event controller can also be forced to emit discrete events on all devices through DISCRETE. This can be used to implement discrete actions triggered through scroll events (e.g. switching across combobox options).
This object was added in 3.24.