Assembly: Use icon overlay for unconnected joints instead of annoying warning. (#22662)

* Core: FeaturePython : Add getOverlayIcons to python interface

* Assembly: unconnected joints icon overlay Fix #22643

* Update src/Mod/Assembly/Gui/ViewProviderAssembly.cpp

Co-authored-by: Kacper Donat <kadet1090@gmail.com>

* Update AssemblyObject.cpp

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update ViewProviderFeaturePython.h

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update ViewProviderFeaturePython.h

* Update JointObject.py

* Update ViewProviderFeaturePython.h

* Update ViewProviderFeaturePython.cpp

* Update Application.cpp

* Update ViewProviderFeaturePython.cpp

* Update ViewProviderFeaturePython.h

* Update ViewProviderAssembly.cpp

---------

Co-authored-by: Kacper Donat <kadet1090@gmail.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

src/Mod/Assembly/App/AssemblyObject.cpp

@@ -939,23 +939,17 @@ void AssemblyObject::removeUnconnectedJoints(std::vector<App::DocumentObject*>&
     }
 
     // Filter out unconnected joints
-    joints.erase(
-        std::remove_if(
-            joints.begin(),
-            joints.end(),
-            [&](App::DocumentObject* joint) {
-                App::DocumentObject* obj1 = getMovingPartFromRef(this, joint, "Reference1");
-                App::DocumentObject* obj2 = getMovingPartFromRef(this, joint, "Reference2");
-                if (!isObjInSetOfObjRefs(obj1, connectedParts)
-                    || !isObjInSetOfObjRefs(obj2, connectedParts)) {
-                    Base::Console().warning(
-                        "%s is unconnected to a grounded part so it is ignored.\n",
-                        joint->getFullName());
-                    return true;  // Remove joint if any connected object is not in connectedParts
-                }
-                return false;
-            }),
-        joints.end());
+    joints.erase(std::remove_if(joints.begin(),
+                                joints.end(),
+                                [&](App::DocumentObject* joint) {
+                                    App::DocumentObject* obj1 =
+                                        getMovingPartFromRef(this, joint, "Reference1");
+                                    App::DocumentObject* obj2 =
+                                        getMovingPartFromRef(this, joint, "Reference2");
+                                    return (!isObjInSetOfObjRefs(obj1, connectedParts)
+                                            || !isObjInSetOfObjRefs(obj2, connectedParts));
+                                }),
+                 joints.end());
 }
 
 void AssemblyObject::traverseAndMarkConnectedParts(App::DocumentObject* currentObj,

src/Mod/Assembly/Gui/ViewProviderAssembly.cpp

@@ -212,6 +212,52 @@ bool ViewProviderAssembly::canDragObjectToTarget(App::DocumentObject* obj,
     return true;
 }
 
+void ViewProviderAssembly::updateData(const App::Property* prop)
+{
+    auto* obj = static_cast<Assembly::AssemblyObject*>(pcObject);
+    if (prop == &obj->Group) {
+        // Defer the icon update until the event loop is idle.
+        // This ensures the assembly has had a chance to recompute its
+        // connectivity state before we query it.
+
+        // We can't capture the raw 'obj' pointer because it may be deleted
+        // by the time the timer fires. Instead, we capture the names of the
+        // document and the object, and look them up again.
+        if (!obj->getDocument()) {
+            return;  // Should not happen, but a good safeguard
+        }
+        const std::string docName = obj->getDocument()->getName();
+        const std::string objName = obj->getNameInDocument();
+
+        QTimer::singleShot(0, [docName, objName]() {
+            // Re-acquire the document and the object safely.
+            App::Document* doc = App::GetApplication().getDocument(docName.c_str());
+            if (!doc) {
+                return;  // Document was closed
+            }
+
+            auto* pcObj = doc->getObject(objName.c_str());
+            auto* obj = static_cast<Assembly::AssemblyObject*>(pcObj);
+
+            // Now we can safely check if the object still exists and is attached.
+            if (!obj || !obj->isAttachedToDocument()) {
+                return;
+            }
+
+            std::vector<App::DocumentObject*> joints = obj->getJoints(false);
+            for (auto* joint : joints) {
+                Gui::ViewProvider* jointVp = Gui::Application::Instance->getViewProvider(joint);
+                if (jointVp) {
+                    jointVp->signalChangeIcon();
+                }
+            }
+        });
+    }
+    else {
+        Gui::ViewProviderPart::updateData(prop);
+    }
+}
+
 bool ViewProviderAssembly::setEdit(int mode)
 {
     if (mode == ViewProvider::Default) {

src/Mod/Assembly/Gui/ViewProviderAssembly.h

@@ -107,6 +107,8 @@ public:
     bool onDelete(const std::vector<std::string>& subNames) override;
     bool canDelete(App::DocumentObject* obj) const override;
 
+    void updateData(const App::Property*) override;
+
     /** @name enter/exit edit mode */
     //@{
     bool setEdit(int ModNum) override;

src/Mod/Assembly/JointObject.py

@@ -573,6 +573,9 @@ class Joint:
         for obj in joint.InList:
             if obj.isDerivedFrom("Assembly::AssemblyObject"):
                 return obj
+            elif obj.isDerivedFrom("Assembly::AssemblyLink"):
+                return self.getAssembly(obj)
+
         return None
 
     def setJointType(self, joint, newType):
@@ -946,6 +949,24 @@ class ViewProviderJoint:
 
         return ":/icons/Assembly_CreateJoint.svg"
 
+    def getOverlayIcons(self):
+        """
+        Return a dictionary of overlay icons.
+        Keys are positions from Gui.IconPosition.
+        Values are the icon resource names.
+        """
+
+        overlays = {}
+
+        assembly = self.app_obj.Proxy.getAssembly(self.app_obj)
+        # Assuming Reference1 corresponds to the first part link
+        if hasattr(self.app_obj, "Reference1"):
+            part = UtilsAssembly.getMovingPart(assembly, self.app_obj.Reference1)
+            if part is not None and not assembly.isPartConnected(part):
+                overlays[Gui.IconPosition.BottomLeft] = "Part_Detached"
+
+        return overlays
+
     def dumps(self):
         """When saving the document this object gets stored using Python's json module.\
                 Since we have some un-serializable parts here -- the Coin stuff -- we must define this method\