do not second-guess which classes use a stylesheet

Change-Id: I76b23bcdca2e7394fd5ab67e8341f4cdb46f8a64

sd/source/core/stlsheet.cxx

@@ -349,18 +349,9 @@ bool SdStyleSheet::IsUsed() const
             if( pListener == this )
                 continue;
 
-            // NULL-Pointer ist im Listener-Array erlaubt
-            if (pListener)
-            {
-                if (pListener->ISA(sdr::properties::AttributeProperties))
-                {
-                    bResult = true;
-                }
-                else if (pListener->ISA(SfxStyleSheet))
-                {
-                    bResult = ((SfxStyleSheet*)pListener)->IsUsed();
-                }
-            }
+            const svl::StyleSheetUser* const pUser(dynamic_cast<svl::StyleSheetUser*>(pListener));
+            if (pUser)
+                bResult = pUser->isUsedByModel();
             if (bResult)
                 break;
         }

svl/Package_inc.mk

@@ -97,6 +97,7 @@ $(eval $(call gb_Package_add_file,svl_inc,inc/svl/strmadpt.hxx,svl/strmadpt.hxx)
 $(eval $(call gb_Package_add_file,svl_inc,inc/svl/style.hrc,svl/style.hrc))
 $(eval $(call gb_Package_add_file,svl_inc,inc/svl/style.hxx,svl/style.hxx))
 $(eval $(call gb_Package_add_file,svl_inc,inc/svl/stylepool.hxx,svl/stylepool.hxx))
+$(eval $(call gb_Package_add_file,svl_inc,inc/svl/stylesheetuser.hxx,svl/stylesheetuser.hxx))
 $(eval $(call gb_Package_add_file,svl_inc,inc/svl/svdde.hxx,svl/svdde.hxx))
 $(eval $(call gb_Package_add_file,svl_inc,inc/svl/svl.hrc,svl/svl.hrc))
 $(eval $(call gb_Package_add_file,svl_inc,inc/svl/svldllapi.h,svl/svldllapi.h))

svl/inc/svl/style.hxx

@@ -34,6 +34,7 @@
 #include <svl/lstner.hxx>
 #include <svl/brdcst.hxx>
 #include <svl/poolitem.hxx>
+#include <svl/stylesheetuser.hxx>
 
 #include <svl/style.hrc>
 
@@ -267,7 +268,7 @@ public:
 //=========================================================================
 
 class SVL_DLLPUBLIC SfxStyleSheet: public SfxStyleSheetBase,
-                     public SfxListener, public SfxBroadcaster
+                     public SfxListener, public SfxBroadcaster, public svl::StyleSheetUser
 {
 public:
                         TYPEINFO();
@@ -276,6 +277,9 @@ public:
                         SfxStyleSheet( const SfxStyleSheet& );
 
     virtual void        Notify( SfxBroadcaster& rBC, const SfxHint& rHint );
+
+    virtual bool        isUsedByModel() const;
+
     virtual bool        SetParent( const UniString& );
 
 protected:

svl/inc/svl/stylesheetuser.hxx

+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#ifndef SVL_STYLESHEETUSER_HXX_INCLUDED
+#define SVL_STYLESHEETUSER_HXX_INCLUDED
+
+namespace svl
+{
+
+/** Test whether object that uses a stylesheet is used itself.
+
+  This interface should be implemented by all classes that use
+  a SfxStyleSheet (and listen on it). It can be queried by the stylesheet
+  to determine if it is really used.
+  */
+class StyleSheetUser
+{
+public:
+    /** Test whether this object is used.
+
+      @return true, if the object is used, false otherwise
+      */
+    virtual bool isUsedByModel() const = 0;
+protected:
+    ~StyleSheetUser() {}
+};
+
+}
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */

svl/source/items/style.cxx

@@ -913,6 +913,11 @@ void SfxStyleSheet::Notify(SfxBroadcaster& rBC, const SfxHint& rHint )
     Forward(rBC, rHint);
 }
 
+bool SfxStyleSheet::isUsedByModel() const
+{
+    return IsUsed();
+}
+
 //////////////////////// SfxStyleSheetPool ///////////////////////////////
 
 SfxStyleSheetPool::SfxStyleSheetPool( SfxItemPool const& rSet)

svx/inc/svx/sdr/properties/attributeproperties.hxx

@@ -21,6 +21,7 @@
 #define _SDR_PROPERTIES_ATTRIBUTEPROPERTIES_HXX
 
 #include <svl/lstner.hxx>
+#include <svl/stylesheetuser.hxx>
 #include <svx/sdr/properties/defaultproperties.hxx>
 #include "svx/svxdllapi.h"
 
@@ -30,7 +31,7 @@ namespace sdr
 {
     namespace properties
     {
-        class SVX_DLLPUBLIC AttributeProperties : public DefaultProperties, public SfxListener
+        class SVX_DLLPUBLIC AttributeProperties : public DefaultProperties, public SfxListener, public svl::StyleSheetUser
         {
             // add style sheet, do all the necessary handling
             void ImpAddStyleSheet(SfxStyleSheet* pNewStyleSheet, sal_Bool bDontRemoveHardAttr);
@@ -82,6 +83,8 @@ namespace sdr
 
             // This is the Notify(...) from 2nd base class SfxListener
             virtual void Notify(SfxBroadcaster& rBC, const SfxHint& rHint);
+
+            virtual bool isUsedByModel() const;
         };
     } // end of namespace properties
 } // end of namespace sdr

svx/inc/svx/svdpage.hxx

@@ -20,6 +20,7 @@
 #ifndef _SVDPAGE_HXX
 #define _SVDPAGE_HXX
 
+#include <svl/stylesheetuser.hxx>
 #include <vcl/bitmap.hxx>
 #include <vcl/print.hxx>
 #include <vcl/gdimtf.hxx>
@@ -368,7 +369,7 @@ public:
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // class SdrPageProperties
 
-class SVX_DLLPUBLIC SdrPageProperties : public SfxListener
+class SVX_DLLPUBLIC SdrPageProperties : public SfxListener, public svl::StyleSheetUser
 {
 private:
     // data
@@ -391,6 +392,8 @@ public:
     // Notify(...) from baseclass SfxListener
     virtual void Notify(SfxBroadcaster& rBC, const SfxHint& rHint);
 
+    virtual bool isUsedByModel() const;
+
     // data read/write
     const SfxItemSet& GetItemSet() const;
     void PutItemSet(const SfxItemSet& rSet);

svx/source/sdr/properties/attributeproperties.cxx

@@ -608,6 +608,18 @@ namespace sdr
                 GetSdrObject().Notify(rBC, rHint);
             }
         }
+
+        bool AttributeProperties::isUsedByModel() const
+        {
+            const SdrObject& rObj(GetSdrObject());
+            if (rObj.IsInserted())
+            {
+                const SdrPage* const pPage(rObj.GetPage());
+                if (pPage && pPage->IsInserted())
+                    return true;
+            }
+            return false;
+        }
     } // end of namespace properties
 } // end of namespace sdr
 

svx/source/svdraw/svdpage.cxx

@@ -17,6 +17,7 @@
  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  */
 
+#include <cassert>
 
 #include <svx/svdpage.hxx>
 
@@ -1196,6 +1197,12 @@ void SdrPageProperties::Notify(SfxBroadcaster& /*rBC*/, const SfxHint& rHint)
     }
 }
 
+bool SdrPageProperties::isUsedByModel() const
+{
+    assert(mpSdrPage);
+    return mpSdrPage->IsInserted();
+}
+
 const SfxItemSet& SdrPageProperties::GetItemSet() const
 {
     return *mpProperties;