prevent expand delegate in Trees to refetch datas if data is already set

diff --git a/src/IMLReader.cs b/src/IMLReader.cs
index 7d87a66d6b48d6cb22ec55a12de922211ceab363..dc7736f5c038039d189a20985d6fc67f41177551 100644 (file)
--- a/src/IMLReader.cs
+++ b/src/IMLReader.cs
@@ -203,8 +203,6 @@ namespace Crow
                                #region Attributes reading
                                if (reader.HasAttributes) {
 
-                                       MethodInfo miAddBinding = typeof(GraphicObject).GetMethod ("BindMember");
-
                                        while (reader.MoveToNextAttribute ()) {
                                                if (reader.Name == "Style")
                                                        continue;

diff --git a/src/ItemTemplate.cs b/src/ItemTemplate.cs
index cc5d507543409d1e77b5641441b1dedbebc3145f..95d00806d9a670eb2c5daccfe3f43fe64885c965 100644 (file)
--- a/src/ItemTemplate.cs
+++ b/src/ItemTemplate.cs
@@ -53,6 +53,8 @@ namespace Crow
                        Type evtType = typeof(EventHandler);
                        Type listBoxType = typeof(ListBox);
 
+                       PropertyInfo piListData = listBoxType.GetProperty ("Data");
+
                        MethodInfo evtInvoke = evtType.GetMethod ("Invoke");
                        ParameterInfo [] evtParams = evtInvoke.GetParameters ();
                        Type handlerArgsType = evtParams [1].ParameterType;
@@ -65,31 +67,48 @@ namespace Crow
 
 
                        #region IL generation
+                       System.Reflection.Emit.Label gotoEnd;
+                       System.Reflection.Emit.Label ifDataIsNull;
+
                        ILGenerator il = dm.GetILGenerator (256);
                        il.DeclareLocal(typeof(GraphicObject));
 
-                       il.Emit (OpCodes.Ldarg_1);
+                       gotoEnd = il.DefineLabel ();
+                       ifDataIsNull = il.DefineLabel ();
+
+                       il.Emit (OpCodes.Ldarg_1);//load sender of expand event
 
                        MethodInfo miFindByName = typeof(GraphicObject).GetMethod("FindByName");
                        il.Emit(OpCodes.Ldstr, "List");
                        il.Emit (OpCodes.Callvirt, miFindByName);
                        il.Emit (OpCodes.Stloc_0);
 
+                       //check that 'Data' of list is not already set
+                       il.Emit (OpCodes.Ldloc_0);
+                       il.Emit (OpCodes.Callvirt, piListData.GetGetMethod ());
+                       il.Emit (OpCodes.Brfalse, ifDataIsNull);
+                       il.Emit (OpCodes.Br, gotoEnd);
+
+                       il.MarkLabel(ifDataIsNull);
+                       //copy the ref of ItemTemplates list TODO: maybe find another way to share it among the nodes?
                        FieldInfo fiTemplates = typeof(TemplatedControl).GetField("ItemTemplates");
                        il.Emit (OpCodes.Ldloc_0);
                        il.Emit (OpCodes.Ldarg_0);
                        il.Emit (OpCodes.Ldfld, fiTemplates);
                        il.Emit (OpCodes.Stfld, fiTemplates);
 
-                       il.Emit (OpCodes.Ldloc_0);
-                       il.Emit (OpCodes.Ldarg_1);
+                       //call 'fetchMethodName' from the dataSource to build the sub nodes list
+                       il.Emit (OpCodes.Ldloc_0);//push 'List' (of sub nodes) into the stack
+                       il.Emit (OpCodes.Ldarg_1);//get the dataSource of the sender
                        il.Emit (OpCodes.Callvirt, typeof(GraphicObject).GetProperty("DataSource").GetGetMethod ());
 
                        MethodInfo miGetDatas = dataType.GetMethod (fetchMethodName, new Type[] {});
                        il.Emit (OpCodes.Callvirt, miGetDatas);
 
-                       il.Emit (OpCodes.Callvirt, listBoxType.GetProperty("Data").GetSetMethod ());
+                       //set 'return' from the fetch method as 'data' of the list
+                       il.Emit (OpCodes.Callvirt, piListData.GetSetMethod ());
 
+                       il.MarkLabel(gotoEnd);
                        il.Emit (OpCodes.Ret);
 
                        #endregion