Previously the client would only learn the mime type of what was being
dropped on it once the drop occurred. To enable more sophisticated
filtering of drag & drop, we now pass along the list of mime types being
dragged to the client with each MouseMove event.
(Note that MouseMove is translated to the various Drag* events in LibGUI
on the client side.)
If a widget accept()'s a "drag enter" event, that widget now becomes
the application-wide "pending drop" widget. That state is cleared if
the drag moves over another widget (or leaves the window entirely.)
These events allow widgets to react when a drag enters/leaves their
rectangle. The enter event carries position + mime type, while the
leave event has no information.
Instead of each window having a bool flag that says whether that window
is currently active, have a pointer to the active window on the app
object instead.
Since RefPtr<T> decrements the ref counter to 0 and after that starts
destructing the object, there is a window where the ref count is 0
and the weak references have not been revoked.
Also change WeakLink to be able to obtain a strong reference
concurrently and block revoking instead, which should happen a lot
less often.
Fixes a problem observed in #4621
It always felt a bit jarring that tooltips would pop in right away when
you hover over a toolbar button. This patch adds a 700ms delay before
they appear, and a 50ms delay before they disappear.
Once a tooltip is up, moving the cursor between two widgets that both
have tooltips will leave the tooltip on screen without delays.
This makes most operations thread safe, especially so that they
can safely be used in the Kernel. This includes obtaining a strong
reference from a weak reference, which now requires an explicit
call to WeakPtr::strong_ref(). Another major change is that
Weakable::make_weak_ref() may require the explicit target type.
Previously we used reinterpret_cast in WeakPtr, assuming that it
can be properly converted. But WeakPtr does not necessarily have
the knowledge to be able to do this. Instead, we now ask the class
itself to deliver a WeakPtr to the type that we want.
Also, WeakLink is no longer specific to a target type. The reason
for this is that we want to be able to safely convert e.g. WeakPtr<T>
to WeakPtr<U>, and before this we just reinterpret_cast the internal
WeakLink<T> to WeakLink<U>, which is a bold assumption that it would
actually produce the correct code. Instead, WeakLink now operates
on just a raw pointer and we only make those constructors/operators
available if we can verify that it can be safely cast.
In order to guarantee thread safety, we now use the least significant
bit in the pointer for locking purposes. This also means that only
properly aligned pointers can be used.
We can't rely on a plain global WeakPtr during application teardown
since destruction order is not defined. Instead, use a NeverDestroyed
to hold the GUI::Application weak pointer. This way it will always
be reliable.
Fixes#3251.
Application::show_tooltip() now keeps track of the application's active
tooltip source widget so it can be updated while being shown when the
same widget updates its tooltip label.
Application::hide_tooltip() will unset the tooltip source widget,
respectively.
This is pretty useful for the ResourceGraph applet's tooltips!
Also re-use the Application::TooltipWindow's rect position in its
set_tooltip() method to avoid flickering from the window temporarily
being moved to 100, 100 and the position adjusted moments later.
Using a command-line argument for this clashed with ArgsParser so let's
use an environment variable instead. I feel like Sergey told me to do
this at some point anyway. :^)
During app teardown, the Application object may be destroyed before
something else, and so having Application::the() return a reference was
obscuring the truth about its lifetime.
This patch makes the API more honest by returning a pointer. While
this makes call sites look a bit more sketchy, do note that the global
Application pointer only becomes null during app teardown.
This commit moves the clipboard from WindowServer into a new Clipboard
service program. Clipboard runs as the unprivileged "clipboard" user
and with a much tighter pledge than WindowServer.
To keep things working as before, all GUI::Application users now make
a connection to Clipboard after making the connection to WindowServer.
It could be interesting to connect to Clipboard on demand, but right
now that would necessitate expanding every GUI app's pledge to include
"unix" and also unveiling the clipboard portal, which I prefer not to.
