[FancyZones] Windows resize on switching layout. (#12792)

src/modules/fancyzones/FancyZonesLib/FancyZones.cpp

@@ -722,6 +722,11 @@ void FancyZones::OnDisplayChange(DisplayChangeType changeType) noexcept
             {
                 Trace::VirtualDesktopChanged();
             }
+
+            if (m_currentDesktopId == GUID_NULL)
+            {
+                Logger::warn("Couldn't retrieve virtual desktop id");
+            }
         }
 
         if (changeType == DisplayChangeType::Initialization)

src/modules/fancyzones/FancyZonesLib/FancyZonesWindowProperties.h

@@ -21,7 +21,7 @@ inline ZoneIndexSet GetZoneIndexSet(HWND window)
 
     std::array<int, 2> data;
     memcpy(data.data(), &handle, sizeof data);
-    uint64_t bitmask = ((uint64_t)data[0] << 32) + data[1];
+    uint64_t bitmask = ((uint64_t)data[1] << 32) + data[0];
     
     if (bitmask != 0)
     {
@@ -39,8 +39,8 @@ inline ZoneIndexSet GetZoneIndexSet(HWND window)
 
 inline void StampWindow(HWND window, Bitmask bitmask) noexcept
 {
-    std::array<int, 2> data = { (bitmask >> 32), static_cast<int>(bitmask) };
+    std::array<int, 2> data = { static_cast<int>(bitmask), (bitmask >> 32) };
     HANDLE rawData;
     memcpy(&rawData, data.data(), sizeof data);
     SetProp(window, ZonedWindowProperties::PropertyMultipleZoneID, rawData);
-}
+}

src/modules/fancyzones/FancyZonesLib/VirtualDesktop.cpp

@@ -167,7 +167,9 @@ std::optional<GUID> VirtualDesktop::GetCurrentVirtualDesktopId() const
         }
     }
 
-    return std::nullopt;
+    desktopId = GetDesktopIdByTopLevelWindows();
+        
+    return desktopId;
 }
 
 std::optional<std::vector<GUID>> VirtualDesktop::GetVirtualDesktopIds(HKEY hKey) const
@@ -208,6 +210,34 @@ std::optional<std::vector<GUID>> VirtualDesktop::GetVirtualDesktopIds() const
     return GetVirtualDesktopIds(GetVirtualDesktopsRegKey());
 }
 
+std::optional<GUID> VirtualDesktop::GetDesktopIdByTopLevelWindows() const
+{
+    using result_t = std::vector<HWND>;
+    result_t result;
+
+    auto callback = [](HWND window, LPARAM data) -> BOOL {
+        result_t& result = *reinterpret_cast<result_t*>(data);
+        result.push_back(window);
+        return TRUE;
+    };
+    EnumWindows(callback, reinterpret_cast<LPARAM>(&result));
+
+    GUID id;
+    BOOL isWindowOnCurrentDesktop = false;
+    for (const auto window : result)
+    {
+        if (m_vdManager->IsWindowOnCurrentVirtualDesktop(window, &isWindowOnCurrentDesktop) == ERROR_SUCCESS && isWindowOnCurrentDesktop)
+        {
+            if (m_vdManager->GetWindowDesktopId(window, &id) == ERROR_SUCCESS && id != GUID_NULL)
+            {
+                return id;
+            }
+        }
+    }
+
+    return std::nullopt;
+}
+
 void VirtualDesktop::HandleVirtualDesktopUpdates()
 {
     HKEY virtualDesktopsRegKey = GetVirtualDesktopsRegKey();

src/modules/fancyzones/FancyZonesLib/VirtualDesktop.h

@@ -25,6 +25,7 @@ private:
     OnThreadExecutor m_virtualDesktopTrackerThread;
     wil::unique_handle m_terminateVirtualDesktopTrackerEvent;
 
-    std::optional<std::vector<GUID>> GetVirtualDesktopIds(HKEY hKey) const;    
+    std::optional<std::vector<GUID>> GetVirtualDesktopIds(HKEY hKey) const;
+    std::optional<GUID> GetDesktopIdByTopLevelWindows() const;
     void HandleVirtualDesktopUpdates();
 };