[kcm/kwinrules] Detect virtual desktops in Wayland

The list of virtual desktops is retrieved using a DBus method, instead of
`KWindowSystem`, to make it work both in Wayland (as well as X11).

FIXED-IN: 5.20
BUG: 416165

kcmkwin/kwinrules/CMakeLists.txt

@@ -11,6 +11,7 @@ set(kwinrules_SRCS
     ../../rules.cpp
     ../../placement.cpp
     ../../utils.cpp
+    ../../virtualdesktopsdbustypes.cpp
     kwinsrc.cpp
     optionsmodel.cpp
     ruleitem.cpp

kcmkwin/kwinrules/ruleitem.cpp

@@ -119,7 +119,7 @@ RuleItem::Type RuleItem::type() const
 
 QVariant RuleItem::value() const
 {
-    if (m_type == Option) {
+    if (m_options && m_type == Option) {
         return m_options->value();
     }
     return m_value;
@@ -127,7 +127,7 @@ QVariant RuleItem::value() const
 
 void RuleItem::setValue(QVariant value)
 {
-    if (m_type == Option) {
+    if (m_options && m_type == Option) {
         m_options->setValue(value);
     }
     m_value = typedValue(value, m_type);

kcmkwin/kwinrules/rulesmodel.cpp

@@ -45,6 +45,9 @@ RulesModel::RulesModel(QObject *parent)
     qmlRegisterUncreatableType<RulesModel>("org.kde.kcms.kwinrules", 1, 0, "RulesModel",
                                                  QStringLiteral("Do not create objects of type RulesModel"));
 
+    qDBusRegisterMetaType<KWin::DBusDesktopDataStruct>();
+    qDBusRegisterMetaType<KWin::DBusDesktopDataVector>();
+
     populateRuleList();
 }
 
@@ -421,6 +424,10 @@ void RulesModel::populateRuleList()
                                         QIcon::fromTheme("virtual-desktops")));
     desktop->setOptionsData(virtualDesktopsModelData());
 
+    connect(this, &RulesModel::virtualDesktopsUpdated,
+            this, [this] { m_rules["desktop"]->setOptionsData(virtualDesktopsModelData()); });
+    updateVirtualDesktops();
+
 #ifdef KWIN_BUILD_ACTIVITIES
     m_activities = new KActivities::Consumer(this);
 
@@ -700,10 +707,10 @@ QList<OptionsModel::Data> RulesModel::windowTypesModelData() const
 QList<OptionsModel::Data> RulesModel::virtualDesktopsModelData() const
 {
     QList<OptionsModel::Data> modelData;
-    for (int desktopId = 1; desktopId <= KWindowSystem::numberOfDesktops(); ++desktopId) {
+    for (const DBusDesktopDataStruct &desktop : m_virtualDesktops) {
         modelData << OptionsModel::Data{
-            desktopId,
-            QString::number(desktopId).rightJustified(2) + QStringLiteral(": ") + KWindowSystem::desktopName(desktopId),
+            desktop.position + 1,  // "desktop" setting uses the desktop position (int) starting at 1
+            QString::number(desktop.position + 1).rightJustified(2) + QStringLiteral(": ") + desktop.name,
             QIcon::fromTheme("virtual-desktops")
         };
     }
@@ -815,4 +822,32 @@ void RulesModel::selectX11Window()
     );
 }
 
+void RulesModel::updateVirtualDesktops()
+{
+    QDBusMessage message = QDBusMessage::createMethodCall(QStringLiteral("org.kde.KWin"),
+                                                          QStringLiteral("/VirtualDesktopManager"),
+                                                          QStringLiteral("org.freedesktop.DBus.Properties"),
+                                                          QStringLiteral("Get"));
+    message.setArguments(QVariantList{
+        QStringLiteral("org.kde.KWin.VirtualDesktopManager"),
+        QStringLiteral("desktops")
+    });
+
+    QDBusPendingReply<QVariant> async = QDBusConnection::sessionBus().asyncCall(message);
+
+    QDBusPendingCallWatcher *callWatcher = new QDBusPendingCallWatcher(async, this);
+    connect(callWatcher, &QDBusPendingCallWatcher::finished, this,
+            [this](QDBusPendingCallWatcher *self) {
+                QDBusPendingReply<QVariant> reply = *self;
+                self->deleteLater();
+                if (!reply.isValid()) {
+                    return;
+                }
+                m_virtualDesktops = qdbus_cast<KWin::DBusDesktopDataVector>(reply.value());
+                emit virtualDesktopsUpdated();
+            }
+    );
+}
+
+
 } //namespace

kcmkwin/kwinrules/rulesmodel.h

@@ -22,8 +22,9 @@
 #define KWIN_RULES_MODEL_H
 
 #include "ruleitem.h"
-#include "rulesettings.h"
 #include <rules.h>
+#include <rulesettings.h>
+#include <virtualdesktopsdbustypes.h>
 
 #include <QAbstractListModel>
 #include <QSortFilterProxyModel>
@@ -96,6 +97,8 @@ signals:
     void warningMessageChanged();
     void suggestionsChanged();
 
+    void virtualDesktopsUpdated();
+
 private:
     void populateRuleList();
     bool wmclassWarning() const;
@@ -103,6 +106,7 @@ private:
     QString defaultDescription() const;
 
     static const QHash<QString, QString> x11PropertyHash();
+    void updateVirtualDesktops();
 
     QList<OptionsModel::Data> windowTypesModelData() const;
     QList<OptionsModel::Data> virtualDesktopsModelData() const;
@@ -117,6 +121,7 @@ private slots:
 private:
     QList<RuleItem *> m_ruleList;
     QHash<QString, RuleItem *> m_rules;
+    DBusDesktopDataVector m_virtualDesktops;
 #ifdef KWIN_BUILD_ACTIVITIES
     KActivities::Consumer *m_activities;
 #endif