How to drag and drop both default and custom node from the stencil into the WPF Diagram (SfDiagram)?

In the WPF Diagram, if your Stencil contains symbols derived from both the NodeViewModel and CustomNodeViewModel classes, where CustomNodeViewModel is a subclass of NodeViewModel, and the Nodes property of SDiagram is set up as an ObservableCollection of either NodeViewModel or CustomNodeViewModel, you might face issues when performing drag-and-drop operations from the stencil to the diagram. To avoid these problems, consider initializing the Nodes property as NodeCollection. Here is a simple code example to demonstrate how to do that:

C# Code Snippet:

// Initialize the Diagram
SfDiagram Diagram = new SfDiagram();

// Set up a new NodeCollection for diagram nodes
Diagram.Nodes = new NodeCollection(); 

Conclusion
I hope you enjoyed learning about how to drag and drop a custom node from the stencil into the WPF Diagram.

You can refer to our WPF Diagram feature tour page to learn about its other groundbreaking feature representations and documentation, and how to quickly get started with configuration specifications. You can also explore our WPF Diagram example to understand how to create and manipulate data.

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