Dropdown

Current implementation: PromeoDropdownV2. The canonical dropdown trigger

• menu pair, using the published DropdownMotion defaults (currently sourced from defaults/patterns/dropdown_v2.json) for entry / exit animation timing. The trigger fills its parent constraints unless width is set explicitly.

Preview

PromeoDropdownV2 via Flutter micro-app at /preview. Live state pushed via postMessage.

Code

From snapshot v2026.05.15-001. Reflects the published defaults, not live playground state — see PRD 02 §6 snapshot-fidelity rule.

// from snapshot v2026.05.15-001
import 'package:flutter/material.dart';
import 'package:promeo_design_system/promeo_design_system.dart';

class DropdownSample extends StatefulWidget {
  const DropdownSample({super.key});
  @override
  State<DropdownSample> createState() => _DropdownSampleState();
}

class _DropdownSampleState extends State<DropdownSample> {
  String _value = 'opt1';

  @override
  Widget build(BuildContext context) {
    return PromeoDropdownV2(
      value: _value,
      items: const [
        DropdownItem(value: 'opt1', label: 'Option 1'),
        DropdownItem(value: 'opt2', label: 'Option 2'),
        DropdownItem(value: 'opt3', label: 'Option 3'),
      ],
      onChanged: (v) => setState(() => _value = v),
  motion: const DropdownMotion(
    durationMs: 240,
    exitEasing: 'easeInOut',
  ),
    );
  }
}

API

Prop	Type	Default	Notes
value	String	required	Currently-selected item value
items	List	required	Pass Strings or DropdownItem(value, label)
onChanged	ValueChanged<String>	required	Fired when the user picks an item
disabled	bool	false	Locks interaction; renders disabled style
width	double?	null	Trigger width; null = fill parent constraints
placement	DropdownPlacement	auto	auto flips on viewport space; top / bottom force
motion	DropdownMotion?	null	Per-instance motion override; null = use registry defaults
open	bool?	null	Controlled-open mode. Pair with onOpenChange
onOpenChange	ValueChanged<bool>?	null	Fired when open state changes

Notes

• The snippet above reflects the currently-published snapshot’s DropdownMotion overrides; drag the Workshop lab sliders + Apply + Sync to bump the snapshot tag (PRD 02 §6 + slice 3.5).
• Width default = “fill parent” is intentional (regression from the width: 252 incident, 2026-05-14). Pass a concrete width only when the layout demands it.