Views now have a cursor index (retrievable via cursor_index()) which
is separate from the selection.
Until now, we've been using the first entry in the selection as
"the cursor", which gets messy whenever you want to select more than
one index in the model.
When setting the cursor, the selection is implicitly updated as well
to maintain the old behavior (for the most part.)
Going forward, this will make it much easier to implement things like
shift-select (extend selection from cursor) and such. :^)
A view can now be told to move its cursor in one of multiple directions
as specified by the CursorMovement enum.
View subclasses can override move_cursor(CursorMovement) to implement
their own cursor behavior. By default, AbstractView::move_cursor() is
a no-op.
This patch improves code sharing between TableView and TreeView. :^)
Before, we had about these occurrence counts:
COPY: 13 without, 33 with
MOVE: 12 without, 28 with
Clearly, 'with' was the preferred way. However, this introduced double-semicolons
all over the place, and caused some warnings to trigger.
This patch *forces* the usage of a semi-colon when calling the macro,
by removing the semi-colon within the macro. (And thus also gets rid
of the double-semicolon.)
If both the row and column headers are visible, we now also show a
button in the top left corner. This avoids the headers overlapping
each other when you scroll the contents.
In the future, this could be hooked up to a "select all" action.
The view needs to recompute the scrollable content size whenever this
happens, so let's always notify it. Previously we were only doing this
when resizing columns with interactively (not programmatically.)
This patch introduces the HeaderView class, which is a widget that
implements the column headers of TableView and TreeView.
This greatly simplifies event management in the view implementations
and also makes it much easier to eventually implement row headers.
This patch adds Widget::children_clip_rect() which can be overridden
to tighten clipping of a widget's children. The default implementation
simply returns Widget::rect().
A Widget can now have a focus proxy widget. Questions about focus are
redirected to the proxy if present. This is useful if a widget could
logically get focus, but wants one of its child widgets to actually
handle it.
Also clamp mouse events to frame rect when dragging outside of the color
field area.
Store hue separately from color, to prevent pure white resetting the hue
back to 0.
With this, if clicking the gutter until the scrubber's below the
mouse and then releasing the mouse, the scrubber is correctly
highlighted after releasing the mouse.
While left-mouse is pressed on any component (arrows, gutter, scrubber),
don't draw hover states for components other than the pressed component.
For example, while clicking the arrow-down button and then dragging
around, the arrow-up button and the scrubber now aren't highlighted.
This also means that during a gutter drag session, the scrubber
isn't highlighted while it's under the mouse cursor. That makes
sense, since we get the gutter drag behavior, not the scrubber
drag behavior, in this case.
The highlight is supposed to indicate "clickability", but if the
mouse is already down, they can't be clicked.
Now that I check for it, this seems to match the scrollbar behavior
on Windows.
And remove the now-redundant members m_scrubbing, m_scrubber_in_use,
and m_automatic_scrolling_kind.
This also made it clear that we weren't canceling the autoscroll
timer if the scrollbar got disabled while it was scrolling, so
this fixes that too.
Note that m_hovered_component is only updated on mouse move, not while
just keeping left down. It's arguably wrong to update it on mouse move
while the mouse is down, I'll probably change things so that it doesn't
update there either.
The behavior on click-in-gutter-keep-left-down-then-move-mouse varies
a surprising amount between platforms. This implements the macOS
behavior where the scrubber follows the mouse direction while scrolling
by pages. (To be precise, it's the macOS behavior of Finder and Preview,
Safari has Windows's scrollbar behavior).
On Windows, the first click locks in the scroll direction and then
dragging the mouse off the scrubber in that direction makes the
scroll continue, but dragging it off the other direction has no effect.
I see no reason for that behavior.
Rather than disable and re-enable the timer, always keep it active
and make it do collision checks to decide if it should have an effect.
This is because set_automatic_scrolling_active(true) calls the
timeout callback immediately before starting the timer, and
when clicking the gutter this callback could disable the timer
again (if the first page scroll put the scrubber under the cursor).
Intead of making set_automatic_scrolling_active() work when it's
called reentrantly (which is easy: just swap the order of
on_automatic_scrolling_timer_fired() and timer->start() so that
on_automatic_scrolling_timer_fired() can immediately stop the
timer again, but it's confusing), make the timer check if it
should do anything.
This is keyed off m_last_mouse_position instead of
m_hovered_component because m_hovered_component is a visual state
and we arguably shouldn't modify it while the left mouse button
is down (as it indicated what part is activated on click).
Most callers of set_automatic_scrolling_active() also change
m_automatic_scrolling_kind, and it makes it possible to make timer
behavior dependent on the autoscroll kind later.
It's slightly less code, and m_scrubber_in_use is now set correctly
when shift-clicking, keeping the mouse button down, and then
dragging the throbber.
The shift-click brings the scrubber under the cursor, and then
the scrubber_rect().contains() condition is true and both scrubber
drags and shift-click-drags are handled the same naturally.
