This ensures that rapidly clicking a button doesn't look like it's
"swallowing" some of the mouse events.
This already worked okay due to a hack in Window, but this will allow us
to get rid of that hack.
In most situations, Widget::update() is preferable, since that allows us
to coalesce repaints and avoid redundant work, reducing system load.
However, there are some cases where you really want a paint to happen
right away, to make sure that the user has a chance to see a short-lived
visual state.
We're using the outermost right and bottom child edges to determine the
width and height of the ICB. However, since these edges are *within* the
respective child's rectangle, we have to add 1 when turning them into
width and height values.
This fixes an issue where scrolling a document would shrink its viewport
rect by 1 pixel (on both axes) on every scroll step.
Before this change, using the Tab key would cycle through all the
individual buttons in an exclusive group (e.g radio buttons.)
This felt wrong, since a group of exclusive buttons is really a single
logical input with a limited number of possible choices.
This patch makes such groups behave as a single focusable unit instead,
by dynamically updating the focus policies so that only the currently
checked button is focusable.
We also allow keyboard navigation within the button group via the arrow
keys. This had to be specialized in GUI::AbstractButton, since the
default behavior of arrow keys is to traverse the focus chain.
The only reason it wasn't const before (and why we had a const_cast
hack) was to support ImageStyleValue's constructor taking it, which no
longer applies. `hack_count--;` :^)
This always felt awkward to me, and required a few other hacks to make
it work. Now, the request is only started when `load_bitmap()` is
called, which we do inside `NodeWithStyle::apply_style()`.
Showing the selection in non-focused text editors was not really useful,
since refocusing the widget would clear or change the selection
immediately anyway.
Note that TextEditors in inactive windows can still be the focused
widget within that window, and will still be painted with an "inactive"
looking selection.
The FilePicker has implemented its common locations tray as a composite
widget built from a GUI::Frame with a bunch of GUI::Button inside it.
The problem with that is that it creates a long and annoying chain of
keyboard-focusable widgets.
This patch adds GUI::Tray, which is a dedicated single widget that
implements the same UI element, but without child widgets.
