vyuh_node_flow library

A flexible, high-performance node-based flow editor for Flutter.

vyuh_node_flow is a comprehensive Flutter package for building interactive node-based editors, visual programming interfaces, workflow editors, diagrams, and data processing pipelines. Inspired by React Flow, it provides a rich set of features for creating sophisticated visual programming experiences.

Features

• Interactive Node Editor: Drag, resize, and connect nodes with an intuitive interface
• Flexible Connections: Support for multiple connection styles (bezier, straight, step) with customizable endpoints and labels
• Rich Theming: Comprehensive theming system for nodes, ports, and connections
• Viewport Controls: Pan, zoom, and minimap support for navigating large graphs
• State Management: Built on MobX for reactive, observable state management
• Grouping & Comments: GroupNode for visual grouping, CommentNode for floating text comments
• Validation: Built-in connection validation and custom validation support
• Keyboard Shortcuts: Extensive keyboard shortcuts for productivity
• Serialization: JSON serialization support for saving and loading graphs

Core Components

Graph Components

• NodeFlowEditor: The main interactive editor widget
• NodeFlowViewer: A read-only viewer for displaying node graphs
• NodeFlowController: Controller for managing graph state and operations
• NodeFlowConfig: Configuration for editor behavior and appearance
• Viewport: Manages pan, zoom, and transformation of the canvas
• NodeFlowMinimap: Minimap widget for navigation

Nodes

• Node: The core node model representing graph nodes
• GroupNode: Special node for visually grouping other nodes
• CommentNode: Special node for floating text comments
• NodeWidget: Base widget for rendering nodes
• NodeData: Custom data interface for node content
• InteractionState: Tracks node interaction states (hover, selected, etc.)

Connections

• Connection: Model representing edges between nodes
• ConnectionEndpoint: Defines connection start and end points
• ConnectionStyleBase: Base class for connection rendering styles
• ConnectionTheme: Theming for connection appearance
• ConnectionValidation: Interface for validating connections

Ports

• Port: Model for node input/output ports
• PortTheme: Theming for port appearance

Spatial Index

• SpatialQueries: Read-only interface for spatial queries and hit testing

Basic Usage

import 'package:vyuh_node_flow/vyuh_node_flow.dart';
import 'package:flutter/material.dart';

class MyNodeEditor extends StatefulWidget {
  @override
  State<MyNodeEditor> createState() => _MyNodeEditorState();
}

class _MyNodeEditorState extends State<MyNodeEditor> {
  late NodeFlowController controller;

  @override
  void initState() {
    super.initState();
    controller = NodeFlowController(
      graph: Graph(
        nodes: [
          Node(id: 'node-1', position: Offset(100, 100)),
          Node(id: 'node-2', position: Offset(300, 100)),
        ],
        connections: [
          Connection(
            id: 'conn-1',
            source: ConnectionEndpoint(nodeId: 'node-1'),
            target: ConnectionEndpoint(nodeId: 'node-2'),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: NodeFlowEditor(
        controller: controller,
        config: NodeFlowConfig(),
      ),
    );
  }

  @override
  void dispose() {
    controller.dispose();
    super.dispose();
  }
}

State Management

This library uses MobX for reactive state management. All core models are observable, enabling automatic UI updates when the graph state changes.