Flutter Gantt Chart

A production-ready, fully customizable Gantt chart widget for Flutter applications.

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Features

• 💓 Scrollable timeline view
• ↔ Draggable
• 🎈 Complete visual customization
• 🛳 Hierarchical activities with parent/child relationships
• 🙳 Activity segments with custom styling
• 👅 Built-in date utilities and calculations
• 🚀 Optimized for performance
• 😱 Responsive across all platforms

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Installation

Add to your pubspec.yaml:

yaml dependencies: flutter_gantt: <latest-version>

Then run:

bash flutter pub get

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Quick Start

import 'package:flutter_gantt/flutter_gantt.dart';

Gantt(
  theme: GanttTheme.of(context),
  activitiesAsync: (startDate, endDate, activity) async => _activities,
  holidaysAsync: (startDate, endDate, holidays) async _holidays,
  onActivityChanged: (activity, start, end) {
    if (start != null && end != null) {
      debugPrint('$activity was moved (Event on widget)');
    } else if (start != null) {
      debugPrint(
        '$activity start was moved (Event on widget)',
      );
    } else if (end != null) {
      debugPrint('$activity end was moved (Event on widget)');
    }
  },
),

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Documentation

Core Components

Gantt Widget

The main chart container with these key properties:

Property	Type	Description
startDate	DateTime	Initial visible date
activities	List	Activities to display
holidays	List	Special dates to highlight
theme	GanttTheme	Visual customization
controller	GanttController	Programmatic control

GanttActivity

Represents a task with:

GanttActivity(
  start: DateTime.now(),
  end: DateTime.now().add(Duration(days: 5)),
  title: 'Task Name',
  color: Colors.blue,
  // Optional:
  children: [/* sub-tasks */],
  segments: [/* phases */],
  onCellTap: (activity) => print('Tapped ${activity.title}'),
)

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Advanced Features

[Programmatic Control:]

final controller = GanttController(
    startDate: DateTime.now(),
    daysViews: 30,
);

// Navigate timeline
controller.next(days: 7);   // Move forward
controller.prev(days: 14);  // Move backward

// Update data
controller.setActivities(newActivities);

[Custom Builders:]

GanttActivity(
  cellBuilder: (date) => YourCustomWidget(date),
  titleWidget: YourTitleWidget(),
)

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Examples

Explore complete examples in the example folder.

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Contributing

We welcome contributions!

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License

MIT – See LICENSE for details.

Roadmap

• Added limitations when dragging
• Improving documentation
• Implementing cell segments
• Improving mobile usability