docs: Add details about grabs

Mention implicit grabs, (lack of) explicit grabs, and popup
windows.
This commit is contained in:
Matthias Clasen 2013-03-30 01:11:47 -04:00 committed by Kristian Høgsberg
parent a4d2b00ae2
commit 29ddfdd0df

View File

@ -232,6 +232,14 @@
focus. Seats are global objects. Pointer events are delivered
in surface local coordinates.
</para>
<para>
The compositor maintains an implicit grab when a button is
pressed, to ensure that the corresponding button release
event gets delivered to the same surface. But there is no way
for clients to take an explicit grab. Instead, surfaces can
be mapped as 'popup', which combines transient window semantics
with a pointer grab.
</para>
<para>
See <xref linkend="protocol-spec-interface-wl_seat"/> for the
protocol description.