A better solution to prevent directly instantiating a module to itself

git-svn-id: https://www.simantics.org/svn/simantics/sysdyn/trunk@18385 ac1ea38d-2e2b-0410-8846-a27921b304fc

diff --git a/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java b/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java
index 6c0cbf61d363676fe45aeb82e50322e55a71de61..5c434c2c8517ff35901678027b2e69f08de5c923 100644 (file)
--- a/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java
+++ b/org.simantics.sysdyn.ui/src/org/simantics/sysdyn/ui/editor/participant/SysdynPopulateElementDropParticipant.java
@@ -1,25 +1,22 @@
 package org.simantics.sysdyn.ui.editor.participant;\r
 \r
-import java.awt.datatransfer.Transferable;\r
-import java.awt.datatransfer.UnsupportedFlavorException;\r
 import java.awt.dnd.DropTargetDragEvent;\r
-import java.io.IOException;\r
+import java.util.ArrayList;\r
+import java.util.Collection;\r
 \r
-import org.eclipse.core.runtime.IAdaptable;\r
-import org.eclipse.jface.viewers.IStructuredSelection;\r
 import org.simantics.db.ReadGraph;\r
 import org.simantics.db.Resource;\r
 import org.simantics.db.exception.DatabaseException;\r
 import org.simantics.db.request.Read;\r
 import org.simantics.diagram.adapter.GraphToDiagramSynchronizer;\r
 import org.simantics.diagram.ui.DiagramModelHints;\r
+import org.simantics.g2d.dnd.ElementClassDragItem;\r
 import org.simantics.g2d.dnd.IDnDContext;\r
+import org.simantics.g2d.element.handler.impl.StaticObjectAdapter;\r
 import org.simantics.modeling.ModelingResources;\r
 import org.simantics.modeling.ui.diagramEditor.PopulateElementDropParticipant;\r
 import org.simantics.structural.stubs.StructuralResource2;\r
 import org.simantics.sysdyn.SysdynResource;\r
-import org.simantics.ui.dnd.LocalObjectTransfer;\r
-import org.simantics.ui.dnd.LocalObjectTransferable;\r
 \r
 public class SysdynPopulateElementDropParticipant extends PopulateElementDropParticipant {\r
 \r
@@ -29,66 +26,46 @@ public class SysdynPopulateElementDropParticipant extends PopulateElementDropPar
 \r
     @Override\r
     public void dragEnter(DropTargetDragEvent dtde, IDnDContext dp) {\r
-        Transferable tr = dtde.getTransferable();\r
-        if (tr.isDataFlavorSupported(LocalObjectTransferable.FLAVOR)) {\r
-            // This must be done to have SWT transfer set the source data\r
-            Object obj = null;\r
-            try {\r
-                obj = tr.getTransferData(LocalObjectTransferable.FLAVOR);\r
-            } catch (UnsupportedFlavorException e) {\r
-                e.printStackTrace();\r
-            } catch (IOException e) {\r
-                e.printStackTrace();\r
-            }\r
-            \r
-            // Check SWT\r
-            if (!(obj instanceof IStructuredSelection)) {\r
-                obj = LocalObjectTransfer.getTransfer().getObject();\r
-            }\r
-            \r
-            if (obj instanceof IStructuredSelection) {\r
-                final IStructuredSelection sel = (IStructuredSelection) obj;\r
-                if (!sel.isEmpty()) {\r
-                       \r
-                       boolean allowed = true;\r
-                       try {\r
-                               allowed = synchronizer.getSession().syncRequest(new Read<Boolean>(){\r
+        super.dragEnter(dtde, dp);\r
+        \r
+        // Check that user is not trying to populate a module to itself. \r
+        // This doesn't prevent infinite recursion if there is one module between two exactly the same modules.\r
+        // e.g. WorkModule -> WokrforceModule -> WorkModule creates an infinite recursion\r
+        final Collection<ElementClassDragItem> items = dp.getItemsByClass(ElementClassDragItem.class);\r
+        if(!items.isEmpty()) {\r
+                Collection<ElementClassDragItem> unvalidModules = null;\r
+               try {\r
+                       unvalidModules = synchronizer.getSession().syncRequest(new Read<Collection<ElementClassDragItem>>() {\r
 \r
-                                                       @Override\r
-                                                       public Boolean perform(ReadGraph graph)\r
-                                                                       throws DatabaseException {\r
-                                           for (Object elm : sel.toList()) {\r
-                                               if (elm instanceof IAdaptable) {\r
-                                                       Object r = ((IAdaptable) elm).getAdapter(Resource.class);\r
-                                                       if(r != null && r instanceof Resource) {\r
-                                                               Resource resource = (Resource)r;\r
-                                                               SysdynResource sr = SysdynResource.getInstance(graph);\r
-                                                               if(graph.isInheritedFrom(resource, sr.ModuleSymbol)) {\r
-                                                                       Resource module = graph.getSingleObject(resource, ModelingResources.getInstance(graph).SymbolToComponentType);\r
-                                                                       Resource configuration = graph.getSingleObject(module, StructuralResource2.getInstance(graph).IsDefinedBy);\r
-                                                                       Resource dia = graph.getSingleObject(configuration, ModelingResources.getInstance(graph).CompositeToDiagram);\r
-                                                                       Resource editorDia = diagram.getHint(DiagramModelHints.KEY_DIAGRAM_RESOURCE);\r
-                                                                       if(dia.equals(editorDia))\r
-                                                                               return false;\r
-                                                               }\r
-                                                       }\r
-                                               }\r
-                                           }\r
-                                                               return true;\r
-                                                       }\r
-                                                       \r
-                                               });\r
-                                       } catch (DatabaseException e) {\r
-                                               e.printStackTrace();\r
+                                       @Override\r
+                                       public Collection<ElementClassDragItem> perform(ReadGraph graph)\r
+                                                       throws DatabaseException {\r
+                                                Collection<ElementClassDragItem> unvalidModules = new ArrayList<ElementClassDragItem>();\r
+                                               for(ElementClassDragItem item : items) {\r
+                                                       StaticObjectAdapter soa = item.getElementClass().getSingleItem(StaticObjectAdapter.class);\r
+                                                       Resource type = soa.adapt(Resource.class);\r
+                                                       \r
+                                       SysdynResource sr = SysdynResource.getInstance(graph);\r
+                                       if(graph.isInheritedFrom(type, sr.ModuleSymbol)) {\r
+                                               Resource module = graph.getSingleObject(type, ModelingResources.getInstance(graph).SymbolToComponentType);\r
+                                               Resource configuration = graph.getSingleObject(module, StructuralResource2.getInstance(graph).IsDefinedBy);\r
+                                               Resource dia = graph.getSingleObject(configuration, ModelingResources.getInstance(graph).CompositeToDiagram);\r
+                                               Resource editorDia = diagram.getHint(DiagramModelHints.KEY_DIAGRAM_RESOURCE);\r
+                                               if(dia.equals(editorDia))\r
+                                                       unvalidModules.add(item);\r
+                                       }\r
+                                               }\r
+                                               return unvalidModules;\r
                                        }\r
-                                       \r
-                                       // Trying to populate an instance of self to diagram -> infinite recursion\r
-                                       // This limitation should be removed by allowing differentation (copies) from modules. i.e. detaching from class and creating a new module type\r
-                                       if(!allowed)\r
-                                               return;\r
-                }\r
-            }\r
+                               });\r
+                       } catch (DatabaseException e) {\r
+                               e.printStackTrace();\r
+                       }\r
+                       if(!unvalidModules.isEmpty()) {\r
+                               for(ElementClassDragItem item : unvalidModules) {\r
+                                       dp.remove(item);\r
+                               }\r
+                       }\r
         }\r
-        super.dragEnter(dtde, dp);\r
     }\r
 }\r