flutter_fancy_tree_view

A Flutter collection of widgets and slivers that helps bringing your hierarchical data to life.

This package uses a set of callbacks to traverse your hierarchical data in depth first order, collecting the needed information in a simple dart list (the flat representation of the tree) to then lazily render the tree nodes to the screen using slivers.

Screenshots


Blank Indentation
Connecting Lines
Scoping Lines

Installation

Run this command:

flutter pub add flutter_fancy_tree_view

This will add a line like this to your package's pubspec.yaml (and run an implicit flutter pub get):

dependencies:
  flutter_fancy_tree_view: any

Now in your Dart code, you can use:

import 'package:flutter_fancy_tree_view/flutter_fancy_tree_view.dart';

⚠️ Warning

Please, treat version 1.0 as a whole new package. Migrating from previous versions is discouraged as the package went through a major rewrite and has many breaking changes.

Features

Dynamic "Tree Node" Modeling
Works with any Widget
Indentation Guides
Expand/Collapse Animations
Sliver tree variants

For a hands on experience of the features, visit the live demo app. The source code for the demo app can be found in the example directory.

Getting Started

Head over to example/example.md for a well commented example of the basic usage of this package. Also, check out the example/lib/src/examples folder which has some feature specific examples.

Usage

Create a "TreeNode" model to store your data

class MyTreeNode {
  const MyTreeNode({
    required this.title,
    this.children = const <MyTreeNode>[],
  });

  final String title;
  final List<MyTreeNode> children;
}

Create/Fetch your hierarchical data

final List<MyTreeNode> roots = [
  const MyTreeNode(title: 'My static root node'),
  ...fetchOtherRootNodes(),
];

Instantiate a TreeController.

final treeController = TreeController<MyTreeNode>(
  roots: roots,
  childrenProvider: (MyTreeNode node) => node.children,
);

Pass the controller to a TreeView and provide a widget builder to map your data into widgets. Make sure to include a way to toggle the tree nodes' expansion state and a TreeIndentation widget to properly indent them.

@override
Widget build(BuildContext context) {
  return AnimatedTreeView<MyTreeNode>(
    treeController: treeController,
    nodeBuilder: (BuildContext context, TreeEntry<MyTreeNode> entry) {
      return InkWell(
        onTap: () => treeController.toggleExpansion(entry.node),
        child: TreeIndentation(
          entry: entry,
          child: Text(entry.node.title),
        ),
      );
    },
  );
}

API Documentation

Head over to the pub.dev api docs.