fix(display): sync Treeland wallpaper previews

src/plugin-display/CMakeLists.txt

@@ -70,6 +70,7 @@ set(Display_Libraries
     ${QT_NS}::Concurrent
     ${DTK_NS}::Core
     dcc-wallpaper-utils
+    dcc-shared-utils
 )
 
 target_link_libraries(${Display_Name} PRIVATE

src/plugin-display/operation/private/displayworker.cpp

@@ -4,10 +4,11 @@
 #include "displayworker.h"
 
 #include "displaymodel.h"
 #include "wallpaperthumbnailutils.h"
+#include "wallpapersync.h"
 
 #include <OutputManager.h>
 #include <TreeLandOutputManager.h>
 #include <VirtualOutputManager.h>
 #include <WallpaperManager.h>
 #include <WayQtUtils.h>
@@ -147,6 +148,11 @@
     m_wallpaperMgr = new WQt::WallpaperManager(this);
     connect(m_wallpaperMgr, &WQt::WallpaperManager::activeChanged, this, &DisplayWorker::onWallpaperManagerActive);
 
+    if (auto *wallpaperSync = WallpaperSync::instance()) {
+        connect(wallpaperSync, &WallpaperSync::wallpaperChanged,
+                this, &DisplayWorker::onSyncedWallpaperChanged, Qt::QueuedConnection);
+    }
+
     // wl_output 的生命周期由 Qt 平台插件维护，跟随 QScreen 即可
     connect(qApp, &QGuiApplication::screenAdded, this, &DisplayWorker::screenAdded);
     connect(qApp, &QGuiApplication::screenRemoved, this, &DisplayWorker::screenRemoved);
@@ -196,6 +202,9 @@
         //    m_model->setResolutionRefreshEnable(m_dccSettings->get(GSETTINGS_SHOW_MUTILSCREEN).toBool());
         //    m_model->setBrightnessEnable(m_dccSettings->get(GSETTINGS_BRIGHTNESS_ENABLE).toBool());
     }
+    else {
+        rebindWallpaperContexts();
+    }
 }
 
 void DisplayWorker::saveChanges()
@@ -405,6 +414,17 @@
         ensureWallpaperContext(screen);
 }
 
+void DisplayWorker::rebindWallpaperContexts()
+{
+    for (auto *screen : QGuiApplication::screens()) {
+        auto *output = m_screen_outputs.value(screen);
+        if (output && m_wallpaperMgr)
+            m_wallpaperMgr->removeWallpaper(output);
+
+        ensureWallpaperContext(screen);
+    }
+}
+
 void DisplayWorker::ensureWallpaperContext(QScreen *screen)
 {
     if (!screen || !m_wallpaperMgr || !m_wallpaperMgr->isActive())
@@ -460,6 +480,21 @@
     }
 }
 
+void DisplayWorker::onSyncedWallpaperChanged(const QString &monitorName, const QString &source, uint sourceType)
+{
+    for (auto it(m_wl_monitors.cbegin()); it != m_wl_monitors.cend(); ++it) {
+        if (it.key()->name() != monitorName)
+            continue;
+
+        QString wallpaper = source;
+        if (sourceType == WallpaperSync::VideoSourceType)
+            wallpaper = resolveVideoThumbnail(source, it.key());
+
+        it.key()->setWallpaper(wallpaper);
+        break;
+    }
+}
+
 void DisplayWorker::updateVirtualOutputs()
 {
     if (!m_virtualOutputMgr)

src/plugin-display/operation/private/displayworker.h

@@ -101,8 +101,10 @@ private Q_SLOTS:
     void updateWallpaper();
     void updateMonitorWallpaper(Monitor *mon);
     void updateWallpaperFromWayland();
+    void rebindWallpaperContexts();
     void ensureWallpaperContext(QScreen *screen);
     void onWallpaperChanged(const QString &fileSource, uint32_t sourceType, uint32_t role);
+    void onSyncedWallpaperChanged(const QString &monitorName, const QString &source, uint sourceType);
     void updateVirtualOutputs();
 
     void onBrightnessChanged(WQt::ColorControl *colorControl, double brightness);

src/plugin-personalization/CMakeLists.txt

@@ -44,6 +44,7 @@ set(Personalization_Libraries
     ${QT_NS}::WaylandClientPrivate
     ${QT_NS}::Concurrent
     dcc-wallpaper-utils
+    dcc-shared-utils
 )
 
 target_include_directories(${LIB_NAME} PUBLIC

src/plugin-personalization/operation/treelandworker.cpp

@@ -21,9 +21,10 @@
 #include <private/qwaylandintegration_p.h>
 #include <private/qwaylandwindow_p.h>
 #include "treelandworker.h"
 #include "operation/personalizationworker.h"
 #include "operation/model/thememodel.h"
 #include "operation/personalizationexport.hpp"
+#include "wallpapersync.h"
 
 #define TYPEWALLPAPER           "wallpaper"
 #define TYPEGREETERBACKGROUND   "greeterbackground"
@@ -450,6 +451,15 @@
         }
     }
 
+    if (role == WallpaperContext::wallpaper_role_desktop) {
+        if (auto *wallpaperSync = WallpaperSync::instance()) {
+            QMetaObject::invokeMethod(wallpaperSync, "setWallpaper", Qt::QueuedConnection,
+                                      Q_ARG(QString, monitorName),
+                                      Q_ARG(QString, dest),
+                                      Q_ARG(uint, type));
+        }
+    }
+
     return true;
 }
 

src/shared-utils/CMakeLists.txt

@@ -20,6 +20,8 @@ set(DCC_SHARED_UTILS_SOURCES
     "dcclocale.cpp"
     "dccdsappletmanager.h"
     "dccdsappletmanager.cpp"
+    "wallpapersync.h"
+    "wallpapersync.cpp"
 )
 
 target_sources(dcc-shared-utils PRIVATE

src/shared-utils/wallpapersync.cpp

@@ -0,0 +1,60 @@
+// SPDX-FileCopyrightText: 2026 UnionTech Software Technology Co., Ltd.
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "wallpapersync.h"
+
+#include <QCoreApplication>
+#include <QPointer>
+#include <QThread>
+
+namespace {
+QPointer<WallpaperSync> wallpaperSyncInstance;
+} // namespace
+
+WallpaperSync *WallpaperSync::instance()
+{
+    if (wallpaperSyncInstance)
+        return wallpaperSyncInstance;
+
+    auto *application = QCoreApplication::instance();
+    if (!application)
+        return nullptr;
+
+    // The lambda is defined inside this static member function, so it inherits
+    // WallpaperSync's access rights and may invoke the private constructor.
+    auto create = [application]() {
+        if (!wallpaperSyncInstance)
+            wallpaperSyncInstance = new WallpaperSync(application);
+    };
+
+    if (QThread::currentThread() == application->thread()) {
+        create();
+    } else {
+        QMetaObject::invokeMethod(application, create, Qt::BlockingQueuedConnection);
+    }
+
+    return wallpaperSyncInstance;
+}
+
+QVariantMap WallpaperSync::wallpaperMap() const
+{
+    return m_wallpaperMap;
+}
+
+void WallpaperSync::setWallpaper(const QString &monitorName, const QString &source, uint sourceType)
+{
+    const QVariantMap wallpaper{ { QStringLiteral("source"), source },
+                                 { QStringLiteral("sourceType"), sourceType } };
+
+    if (m_wallpaperMap.value(monitorName) == wallpaper)
+        return;
+
+    m_wallpaperMap.insert(monitorName, wallpaper);
+    Q_EMIT wallpaperChanged(monitorName, source, sourceType);
+}
+
+WallpaperSync::WallpaperSync(QObject *parent)
+    : QObject(parent)
+{
+}

src/shared-utils/wallpapersync.h

@@ -0,0 +1,31 @@
+// SPDX-FileCopyrightText: 2026 UnionTech Software Technology Co., Ltd.
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#pragma once
+
+#include <QObject>
+#include <QVariantMap>
+
+class WallpaperSync : public QObject
+{
+    Q_OBJECT
+public:
+    static constexpr uint ImageSourceType = 0;
+    static constexpr uint VideoSourceType = 1;
+
+    static WallpaperSync *instance();
+
+    QVariantMap wallpaperMap() const;
+
+public Q_SLOTS:
+    void setWallpaper(const QString &monitorName, const QString &source, uint sourceType);
+
+Q_SIGNALS:
+    void wallpaperChanged(const QString &monitorName, const QString &source, uint sourceType);
+
+private:
+    explicit WallpaperSync(QObject *parent = nullptr);
+
+    QVariantMap m_wallpaperMap;
+};