Bug 366606

Summary:	Missing Compose key support on Wayland
Product:	[Plasma] kwin	Reporter:	Matthias Fauconneau <matthias.fauconneau>
Component:	input	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	RESOLVED UPSTREAM
Severity:	normal
Priority:	NOR
Version First Reported In:	git master
Target Milestone:	---
Platform:	Gentoo Packages
OS:	Linux
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Matthias Fauconneau 2016-08-10 19:28:07 UTC

Composing sequences does not seem to be supported on KDE/Wayland.
I am not sure which part of the software stack should be responsible for translating compose sequences into symbols.
If I understood correctly, it should be handled by the compositor.
But maybe a client-side input method would allow context dependent input. 

Reproducible: Always

Comment 1 Martin Flöser 2016-08-11 05:48:08 UTC

No, compose-key needs to be done by the individual applications and it's Qt which does not handle it, see https://bugreports.qt.io/browse/QTBUG-54792

Compose-key is working correctly on any Xwayland window and on any GTK-Wayland window.

Still KWin would also need compose-key support for internal things like the filter in Present Windows.

Comment 2 Martin Flöser 2016-08-30 06:08:41 UTC

For KWin I just integrated a change to have compose key support. I'll try to get the same into Qt.

commit a98a1b1376a3fdec5ce40f476e7a8a79a9f84b31
Author: Martin Gräßlin <mgraesslin@kde.org>
Date:   Mon Aug 29 17:04:13 2016 +0200

    Support compose key in xkbcommon integration
    
    Summary:
    The Xkb class now creates a compose key table and a state object and
    feeds all key presses through the compose state machine.
    
    Xkb now tracks the latest keysym which is provided through new method
    currentKeysym. This is now used when creating a QKeyEvent instead of
    passing the key code to the xkb state. With that the keysym can also
    be updated through the compose state system.
    
    This only affects KWin internal usage where text is composed, e.g. the
    present windows effect filter. Wayland clients do not gain compose key
    support, though.
    
    Minimum xkbcommon version raised to 0.5 as compose key support is new
    in that version.
    
    Test Plan: Enabled compose key support in keymap and verified through DebugConsole
    
    Reviewers: #kwin, #plasma_on_wayland
    
    Subscribers: plasma-devel, kwin
    
    Tags: #plasma_on_wayland, #kwin
    
    Differential Revision: https://phabricator.kde.org/D2622

Comment 3 Martin Flöser 2016-08-30 09:57:24 UTC

Created a code review against QtWayland, but there is already an older one which never got merged. Setting this report here to RESOLVED UPSTREAM. I tried what's possible.