When using this mode on an AbstractScrollWidget, it was not honoring the
related "scrollbars enabled" setting.
If scrollbars are disabled, they should never be made visible by the
"unnecessary scrollbars" logic.
Renames on_automatic_scrolling_timer_fired() =>
automatic_scrolling_timer_did_fire()
The 'on_' prefix is usually reserved for AK::Function hooks.
Renames set_automatic_scrolling_{active,timer}() =>
set_automatic_scrolling_timer_active()
For consistency, accuracy, and header file A E S T H E T I C S
Banners are abstract widgets which can house additional controls
and information on a temporary basis, popping in from the top of
their parent when needed.
The new min_content_size value is to be set by the subclasses, it is
then used to determine if the scrollbars should be shown after a
resize, but before the content size will be calculated by the following
layout pass.
Implement, and use internally, content_margins() from Widget.
Since AbstractScrollableWidget already has a method called content_size,
the convenience method, with the same name, in Widget has to be
explicitly called.
This commit adds a timer to AbstractScrollableWidget that can be used
when implementing automatic scrolling. By overriding
on_automatic_scrolling_timer_fired() we can calculate the scrolling
delta when dragging objects, and redraw as needed. A helper function,
automatic_scroll_delta_from_position() gives us a delta that
we can use to calculate speed and direction. By default
m_autoscroll_threshold is 20 pixels from the edge, and gives a linear
change in scroll delta.
