[FIX] - Copy problem for two-way drag-drop source <=> target

COMETwebapp/Components/MultiModelEditor/ElementDefinitionTree.razor.cs

@@ -48,7 +48,7 @@ public partial class ElementDefinitionTree
         /// The Iteration
         /// </summary>
         [Parameter]
-        public Iteration Iteration { get; set; }
+        public Iteration InitialIteration { get; set; }
 
         /// <summary>
         /// Gets or sets a value indicating that another model can be selected for this TreeView or not
@@ -154,9 +154,9 @@ public partial class ElementDefinitionTree
         /// </remarks>
         protected override async Task OnAfterRenderAsync(bool firstRender)
         {
-            if (this.ViewModel.Iteration != this.Iteration)
+            if (this.ViewModel.Iteration != this.InitialIteration)
             {
-                this.Iteration = this.ViewModel.Iteration;
+                this.InitialIteration = this.ViewModel.Iteration;
             }
         }
 
@@ -168,7 +168,7 @@ protected override void OnParametersSet()
         {
             base.OnParametersSet();
 
-            this.ViewModel.Iteration = this.Iteration;
+            this.ViewModel.Iteration ??= this.InitialIteration;
         }
 
         /// <summary>

COMETwebapp/Components/MultiModelEditor/MultiModelEditor.razor

@@ -32,7 +32,7 @@
                 <h4>Source Model</h4>
                 <ElementDefinitionTree 
                     @ref="this.SourceTree" 
-                    Iteration="@this.ViewModel.CurrentThing"
+                    InitialIteration="@this.ViewModel.CurrentThing"
                     SelectionChanged="model => { if (model != null) this.TargetTree.ClearSelection(); this.OnElementSelected(model);}"
                     AllowDrag="true"
                     AllowDrop="true"
@@ -50,7 +50,7 @@
                 <h4>Target Model</h4>
                 <ElementDefinitionTree 
                     @ref="this.TargetTree" 
-                    Iteration="@this.ViewModel.CurrentThing"
+                    InitialIteration="@this.ViewModel.CurrentThing"
                     SelectionChanged="model => { if (model != null) this.SourceTree.ClearSelection(); this.OnElementSelected(model);}"
                     AllowDrag="true"
                     AllowDrop="true"

COMETwebapp/Components/MultiModelEditor/MultiModelEditor.razor.cs

@@ -135,7 +135,7 @@ private async Task OnDrop((ElementDefinitionTree, ElementBaseTreeRowViewModel) n
                 if (nodeData.Item2 == null)
                 {
                     // Drop in the same model
-                    await this.ViewModel.CopyAndAddNewElement(elementDefinitionTreeRowViewModel.ElementBase);
+                    await this.ViewModel.CopyAndAddNewElement(nodeData.Item1, elementDefinitionTreeRowViewModel.ElementBase);
                 }
                 else
                 {

COMETwebapp/ViewModels/Components/MultiModelEditor/IMultiModelEditorViewModel.cs

@@ -29,6 +29,7 @@ namespace COMETwebapp.ViewModels.Components.MultiModelEditor
     using COMET.Web.Common.ViewModels.Components.Applications;
 
     using COMETwebapp.Components.ModelEditor;
+    using COMETwebapp.Components.MultiModelEditor;
     using COMETwebapp.ViewModels.Components.ModelEditor;
     using COMETwebapp.ViewModels.Components.ModelEditor.AddParameterViewModel;
     using COMETwebapp.ViewModels.Components.SystemRepresentation;
@@ -97,8 +98,9 @@ public interface IMultiModelEditorViewModel : ISingleIterationApplicationBaseVie
         /// <summary>
         /// Add a new <see cref="ElementDefinition"/> based on an existing <see cref="ElementBase"/>
         /// </summary>
-        /// <param name="elementBase">The <see cref="ElementBase"/></param>
-        Task CopyAndAddNewElement(ElementBase elementBase);
+        /// <param name="elementDefinitionTree">The <see cref="ElementDefinitionTree"/> to copy the node to</param>
+        /// <param name="elementBase">The <see cref="ElementBase"/> to copy</param>
+        Task CopyAndAddNewElement(ElementDefinitionTree elementDefinitionTree, ElementBase elementBase);
 
         /// <summary>
         /// Add a new <see cref="ElementUsage"/> based on an existing <see cref="ElementBase"/>

COMETwebapp/ViewModels/Components/MultiModelEditor/MultiModelEditorViewModel.cs

@@ -36,6 +36,7 @@ namespace COMETwebapp.ViewModels.Components.MultiModelEditor
     using COMET.Web.Common.ViewModels.Components.Applications;
 
     using COMETwebapp.Components.ModelEditor;
+    using COMETwebapp.Components.MultiModelEditor;
     using COMETwebapp.ViewModels.Components.ModelEditor;
     using COMETwebapp.ViewModels.Components.ModelEditor.AddParameterViewModel;
     using COMETwebapp.ViewModels.Components.SystemRepresentation;
@@ -180,12 +181,13 @@ public void OpenAddParameterPopup()
         /// <summary>
         /// Add a new <see cref="ElementDefinition"/> based on an existing <see cref="ElementBase"/>
         /// </summary>
-        /// <param name="elementBase">The <see cref="ElementBase"/></param>
-        public async Task CopyAndAddNewElement(ElementBase elementBase)
+        /// <param name="elementDefinitionTree">The <see cref="ElementDefinitionTree"/> to copy the node to</param>
+        /// <param name="elementBase">The <see cref="ElementBase"/> to copy</param>
+        public async Task CopyAndAddNewElement(ElementDefinitionTree elementDefinitionTree, ElementBase elementBase)
         {
             this.IsLoading = true;
 
-            if (elementBase.GetContainerOfType<Iteration>() == this.CurrentThing)
+            if (elementBase.GetContainerOfType<Iteration>() == elementDefinitionTree.ViewModel.Iteration)
             {
                 var copyCreator = new CopyElementDefinitionCreator(this.sessionService.Session);
 
@@ -209,7 +211,7 @@ public async Task CopyAndAddNewElement(ElementBase elementBase)
 
                 try
                 {
-                    await copyCreator.Copy((ElementDefinition)elementBase, this.CurrentThing);
+                    await copyCreator.Copy((ElementDefinition)elementBase, elementDefinitionTree.ViewModel.Iteration);
                 }
                 catch (Exception exception)
                 {
@@ -230,15 +232,15 @@ public async Task CopyAndAddNewElement(ElementBase elementBase)
         /// <param name="toElementBase">The <see cref="ElementBase"/> where to add the new <see cref="ElementUsage"/> to</param>
         public async Task AddNewElementUsage(ElementBase fromElementBase, ElementBase toElementBase)
         {
-            if (fromElementBase.GetContainerOfType<Iteration>() == this.CurrentThing && toElementBase.GetContainerOfType<Iteration>() == this.CurrentThing)
+            if (fromElementBase.GetContainerOfType<Iteration>() == toElementBase.GetContainerOfType<Iteration>())
             {
                 this.IsLoading = true;
 
                 var thingCreator = new ThingCreator();
 
                 try
                 {
-                    await thingCreator.CreateElementUsage((ElementDefinition)toElementBase, (ElementDefinition)fromElementBase, this.sessionService.Session.OpenIterations.First(x => x.Key == this.CurrentThing).Value.Item1, this.sessionService.Session);
+                    await thingCreator.CreateElementUsage((ElementDefinition)toElementBase, (ElementDefinition)fromElementBase, this.sessionService.Session.OpenIterations.First(x => x.Key == toElementBase.GetContainerOfType<Iteration>()).Value.Item1, this.sessionService.Session);
                 }
                 catch (Exception exception)
                 {