From 18e7e91131a6fbf9dd85e94a9b7494ceeec280f8 Mon Sep 17 00:00:00 2001
From: Ay1nDas <ayandazzz@outlook.com>
Date: Thu, 13 Nov 2025 13:09:16 +0530
Subject: [PATCH] Fix Opacity is not applied with last style if set with object
 and dialog

Add 'StyleSubject::Selection _subject' in 'ObjectPanel'.
So that when style is changed last style used is notified.

Fixes: https://gitlab.com/inkscape/inkscape/-/issues/5811
---
 src/ui/dialog/objects.cpp | 12 ++++++++++--
 src/ui/dialog/objects.h   |  4 ++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/ui/dialog/objects.cpp b/src/ui/dialog/objects.cpp
index 7b0bf5999c..6a5cba2bef 100644
--- a/src/ui/dialog/objects.cpp
+++ b/src/ui/dialog/objects.cpp
@@ -820,7 +820,10 @@ ObjectsPanel::ObjectsPanel()
             os << CLAMP(value, 0.0, 1.0);
             auto css = sp_repr_css_attr_new();
             sp_repr_css_set_property(css, "opacity", os.str().c_str());
-            current_item->changeCSS(css, "style");
+
+            // Apply the style change through the StyleSubject.
+            // This ensures the "last style used" system is notified
+            _subject.setCSS(css);
             sp_repr_css_attr_unref(css);
             DocumentUndo::maybeDone(current_item->document, ":opacity", _("Change opacity"), INKSCAPE_ICON("dialog-object-properties"));
         }
@@ -1036,7 +1039,12 @@ void ObjectsPanel::desktopReplaced()
 {
     layer_changed.disconnect();
 
-    if (auto desktop = getDesktop()) {
+    auto desktop = getDesktop();
+
+    // Update the _subject with the new desktop
+    _subject.setDesktop(desktop);
+
+    if (desktop) {
         layer_changed = desktop->layerManager().connectCurrentLayerChanged(sigc::mem_fun(*this, &ObjectsPanel::layerChanged));
     }
 }
diff --git a/src/ui/dialog/objects.h b/src/ui/dialog/objects.h
index dc5646de5f..06690a506f 100644
--- a/src/ui/dialog/objects.h
+++ b/src/ui/dialog/objects.h
@@ -26,6 +26,7 @@
 #include "ui/widget/color-notebook.h"
 #include "ui/widget/popover-bin.h"
 #include "ui/widget/preferences-widget.h"
+#include "ui/widget/style-subject.h"
 
 namespace Glib {
 class ValueBase;
@@ -152,6 +153,9 @@ private:
     Gtk::TreeRow _clicked_item_row;
     UI::Widget::PopoverBin _popoverbin;
 
+    // Manage selection and apply style changes
+    UI::Widget::StyleSubject::Selection _subject;
+
     void _activateAction(const std::string& layerAction, const std::string& selectionAction);
 
     bool blendModePopup(int x, int y, Gtk::TreeModel::Row row);
-- 
GitLab