kwin/atoms.cpp
Martin Gräßlin ed4a0d0319 Screenedge show support for Clients
This provides a new protocol intended to be used by auto-hiding panels
to make use of the centralized screen edges. To use it a Client can
set an X11 property of type _KDE_NET_WM_SCREEN_EDGE_SHOW to KWin.
As value it takes:
* 0: top edge
* 1: right edge
* 2: bottom edge
* 3: left edge

KWin will hide the Client (hide because unmap or minimize would break
it) and create an Edge. If that Edge gets triggered the Client is shown
again and the property gets deleted. If the Client doesn't border the
specified screen edge the Client gets shown immediately so that we
never end in a situation that we cannot unhide the auto-hidden panel
again. The exact process is described in the documentation of
ScreenEdges. The Client can request to be shown again by deleting the
property.

If KWin gets restarted the state is read from the property and it is
tried to create the edge as described.

As this is a KWin specific extension we need to discuss what it means
for Clients using this feature with other WMs: it does nothing. As
the Client gets hidden by KWin and not by the Client, it just doesn't
get hidden if the WM doesn't provide the feature. In case of an
auto-hiding panel this seems like a good solution given that we don't
want to hide it if we cannot unhide it. Of course there's the option
for the Client to provide that feature itself and if that's wanted we
would need to announce the feature in the _NET_SUPPORTED atom. At the
moment that doesn't sound like being needed as Plasma doesn't want to
provide an own implementation.

The implementation comes with a small test application showing how
the feature is intended to be used.

REVIEW: 115910
2014-02-26 12:54:00 +01:00

82 lines
3.7 KiB
C++

/********************************************************************
KWin - the KDE window manager
This file is part of the KDE project.
Copyright (C) 1999, 2000 Matthias Ettrich <ettrich@kde.org>
Copyright (C) 2003 Lubos Lunak <l.lunak@kde.org>
Copyright (C) 2013 Martin Gräßlin <mgraesslin@kde.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/
#include "atoms.h"
namespace KWin
{
Atoms::Atoms()
: kwin_running(QByteArrayLiteral("KWIN_RUNNING"))
, activities(QByteArrayLiteral("_KDE_NET_WM_ACTIVITIES"))
, wm_protocols(QByteArrayLiteral("WM_PROTOCOLS"))
, wm_delete_window(QByteArrayLiteral("WM_DELETE_WINDOW"))
, wm_take_focus(QByteArrayLiteral("WM_TAKE_FOCUS"))
, wm_change_state(QByteArrayLiteral("WM_CHANGE_STATE"))
, wm_client_leader(QByteArrayLiteral("WM_CLIENT_LEADER"))
, wm_window_role(QByteArrayLiteral("WM_WINDOW_ROLE"))
, wm_state(QByteArrayLiteral("WM_STATE"))
, sm_client_id(QByteArrayLiteral("SM_CLIENT_ID"))
, motif_wm_hints(QByteArrayLiteral("_MOTIF_WM_HINTS"))
, net_wm_context_help(QByteArrayLiteral("_NET_WM_CONTEXT_HELP"))
, net_wm_ping(QByteArrayLiteral("_NET_WM_PING"))
, kde_wm_change_state(QByteArrayLiteral("_KDE_WM_CHANGE_STATE"))
, net_wm_user_time(QByteArrayLiteral("_NET_WM_USER_TIME"))
, kde_net_wm_user_creation_time(QByteArrayLiteral("_KDE_NET_WM_USER_CREATION_TIME"))
, kde_system_tray_embedding(QByteArrayLiteral("_KDE_SYSTEM_TRAY_EMBEDDING"))
, net_wm_take_activity(QByteArrayLiteral("_NET_WM_TAKE_ACTIVITY"))
, net_wm_window_opacity(QByteArrayLiteral("_NET_WM_WINDOW_OPACITY"))
, xdnd_aware(QByteArrayLiteral("XdndAware"))
, xdnd_position(QByteArrayLiteral("XdndPosition"))
, net_frame_extents(QByteArrayLiteral("_NET_FRAME_EXTENTS"))
, kde_net_wm_frame_strut(QByteArrayLiteral("_KDE_NET_WM_FRAME_STRUT"))
, net_wm_sync_request_counter(QByteArrayLiteral("_NET_WM_SYNC_REQUEST_COUNTER"))
, net_wm_sync_request(QByteArrayLiteral("_NET_WM_SYNC_REQUEST"))
, kde_net_wm_block_compositing(QByteArrayLiteral("_KDE_NET_WM_BLOCK_COMPOSITING"))
, kde_net_wm_shadow(QByteArrayLiteral("_KDE_NET_WM_SHADOW"))
, net_wm_opaque_region(QByteArrayLiteral("_NET_WM_OPAQUE_REGION"))
, kde_net_wm_tab_group(QByteArrayLiteral("_KDE_NET_WM_TAB_GROUP"))
, kde_first_in_window_list(QByteArrayLiteral("_KDE_FIRST_IN_WINDOWLIST"))
, kde_color_sheme(QByteArrayLiteral("_KDE_NET_WM_COLOR_SCHEME"))
, kde_skip_close_animation(QByteArrayLiteral("_KDE_NET_WM_SKIP_CLOSE_ANIMATION"))
, kde_screen_edge_show(QByteArrayLiteral("_KDE_NET_WM_SCREEN_EDGE_SHOW"))
, m_dtSmWindowInfo(QByteArrayLiteral("_DT_SM_WINDOW_INFO"))
, m_motifSupport(QByteArrayLiteral("_MOTIF_WM_INFO"))
, m_helpersRetrieved(false)
{
}
void Atoms::retrieveHelpers()
{
if (m_helpersRetrieved) {
return;
}
// just retrieve the atoms once, all others are retrieved when being accessed
// Q_UNUSED is used in the hope that the compiler doesn't optimize the operations away
xcb_atom_t atom = m_dtSmWindowInfo;
Q_UNUSED(atom)
atom = m_motifSupport;
Q_UNUSED(atom)
m_helpersRetrieved = true;
}
} // namespace