Add UserState to build_node

This is necessary if your NodeTemplate struct can't store all the
necessary information to define a new node.

egui_node_graph/src/editor_ui.rs

@@ -68,8 +68,12 @@ where
     >,
     UserResponse: UserResponseTrait,
     ValueType: WidgetValueTrait<Response = UserResponse>,
-    NodeTemplate:
-        NodeTemplateTrait<NodeData = NodeData, DataType = DataType, ValueType = ValueType>,
+    NodeTemplate: NodeTemplateTrait<
+        NodeData = NodeData,
+        DataType = DataType,
+        ValueType = ValueType,
+        UserState = UserState,
+    >,
     DataType: DataTypeTrait<UserState>,
 {
     #[must_use]
@@ -142,7 +146,7 @@ where
                     let new_node = self.graph.add_node(
                         node_kind.node_graph_label(),
                         node_kind.user_data(),
-                        |graph, node_id| node_kind.build_node(graph, node_id),
+                        |graph, node_id| node_kind.build_node(graph, &self.user_state, node_id),
                     );
                     self.node_positions.insert(
                         new_node,

egui_node_graph/src/traits.rs

@@ -108,6 +108,8 @@ pub trait NodeTemplateTrait: Clone {
     type DataType;
     /// Must be set to the custom user `ValueType` type
     type ValueType;
+    /// Must be set to the custom user `UserState` type
+    type UserState;
 
     /// Returns a descriptive name for the node kind, used in the node finder.
     fn node_finder_label(&self) -> &str;
@@ -124,6 +126,7 @@ pub trait NodeTemplateTrait: Clone {
     fn build_node(
         &self,
         graph: &mut Graph<Self::NodeData, Self::DataType, Self::ValueType>,
+        user_state: &Self::UserState,
         node_id: NodeId,
     );
 }

egui_node_graph_example/src/app.rs

@@ -111,6 +111,7 @@ impl NodeTemplateTrait for MyNodeTemplate {
     type NodeData = MyNodeData;
     type DataType = MyDataType;
     type ValueType = MyValueType;
+    type UserState = MyGraphState;
 
     fn node_finder_label(&self) -> &str {
         match self {
@@ -137,6 +138,7 @@ impl NodeTemplateTrait for MyNodeTemplate {
     fn build_node(
         &self,
         graph: &mut Graph<Self::NodeData, Self::DataType, Self::ValueType>,
+        _user_state: &Self::UserState,
         node_id: NodeId,
     ) {
         // The nodes are created empty by default. This function needs to take