Accordion Sliver App Bar

AccordionSliverAppBar is a customizable Flutter package that provides a SliverAppBar with dynamic accordion-style animations. It enables you to create SliverAppBars where sections can expand or collapse based on priorities, creating an engaging and responsive UI.

Demo

"Demo"

Features

  • Accordion behavior for multiple stacked children
  • Vanish animation for children that fade out when collapsed
  • Static children that don't animate
  • Optional overlay builder to layer a widget (e.g., color overlay) on top of the background

Installation

Run command below to add package to pubspec.yaml:

flutter pub add accordion_sliver_app_bar

Usage

For usage instructions and a complete example, check out the example project.

AccordionSliverAppBar Parameters

  • background: A widget placed at the very back of the stack (e.g., a colored container or image).
  • children: A list of AccordionSliverChild objects to stack.
  • backgroundOverlayBuilder: Optional function that takes a progress (0.0–1.0) and returns a widget overlaying the background.
  • floating: Determines if the SliverAppBar should float.

AccordionSliverChild Parameters

  • expandedHeight: The height of the child when fully expanded.
  • collapsedHeight: The height of the child when collapsed.
  • priority: Higher priority children are placed nearer to the top of the stack (expanded first).
  • wrapperBuilder: Wraps the child in any additional widgets (e.g., containers or scroll views).
  • animatedBuilder: Receives a progress parameter from 0.0 (collapsed) to 1.0 (expanded). Use this to animate child widgets.
  • clipBehavior: How to clip content (defaults to Clip.antiAlias).

AccordionSliverChild Additional factories

  • static: The child has the same height expanded or collapsed (no animation).
  • staticVanish: The child is fully visible expanded, and hidden collapsed, without intermediate animation.
  • vanish: The child animates its height and can fade out as it collapses.

Contributions

Contributions are welcome! Feel free to submit issues, feature requests, or pull requests on the GitHub repository.

License

This package is released under the MIT License. See the LICENSE file for details.

Support

If you find this package helpful, please star the repository and share your feedback!

Libraries

accordion_sliver_app_bar
core/extensions