dynamic_properties_panel

Schema-driven property editing panel for Flutter — with a companion DynamicPropertiesController that enables granular rebuilds, bidirectional sync between panel and rendered components, and commit-only callbacks for expensive persistence layers.

Polished controls are included for primitives, enums, objects, arrays, maps, colors, icons, dates, durations, and more — plus widget-slot pickers, breadcrumb navigation, and preset toolbars.

Live demo

Try the production example: https://flutterdynamicpropertiespanel.netlify.app/

Production package notes

This standalone package uses the published color_picker_plus and json_view_plus packages instead of vendored local copies. Its bundled design-system snapshot is also pruned to the internal primitives the panel and example actually use, keeping the package smaller, easier to update, and aligned with the production-ready color and JSON controls used by the example app.

Installation

dependencies:
  dynamic_properties_panel: ^1.0.0

import 'package:dynamic_properties_panel/dynamic_properties_panel.dart';

---

Two ways to use it

1. Controller-based (recommended)

Use this when you want:

• Granular rebuilds (changing one property only rebuilds its control)
• Live updates during drag without full-tree rebuilds
• Bidirectional sync — a rendered preview component writes back to the panel (Storybook-args pattern)
• Explicit save/persist without hidden serialization on every keystroke

import 'package:dynamic_properties_panel/dynamic_properties_panel.dart';

class MyPage extends StatefulWidget { ... }

class _MyPageState extends State<MyPage> {
  late final DynamicPropertiesController _controller;

  @override
  void initState() {
    super.initState();
    _controller = DynamicPropertiesController(initial: loadedValues);
  }

  @override
  void dispose() {
    _controller.dispose();  // mandatory — caller owns lifecycle
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return DynamicPropertiesPanel(
      controller: _controller,
      properties: DynamicPropertyDefinition.listFromJson(schema),
    );
  }

  void _save() {
    // Snapshot on demand — not synced on every change.
    final values = _controller.snapshot();
    persistToDisk(values);
  }
}

2. Map-based (backwards-compatible)

The legacy constructor still works — the panel creates an internal controller. onChanged now fires only on committed changes (drag end, typing complete, preset applied), not on every drag tick:

DynamicPropertiesPanel(
  values: values,
  properties: DynamicPropertyDefinition.listFromJson(schema),
  onChanged: (next) => setState(() => values = next),
)

---

DynamicPropertiesController API

// Construction
final controller = DynamicPropertiesController(initial: {'fontSize': 16});

// Reading
controller['fontSize'];              // dynamic — null if never set
controller.notifierFor('fontSize');  // ValueNotifier<dynamic>
controller.hasValue('fontSize');     // bool — has it been explicitly set?
controller.snapshot();               // Map<String,dynamic> — deep-copied
controller.snapshotShallow();        // Map<String,dynamic> — cheap

// Writing — every write fires all listeners and the commits stream.
controller['fontSize'] = 18;                          // idiomatic
controller.setValue('fontSize', 18);                  // equivalent
controller.applyAll({'a': 1, 'b': 2});                // bulk

// Listening
controller.addListener(() { ... });                   // any change
ValueListenableBuilder(                               // single property, granular
  valueListenable: controller.notifierFor('enabled'),
  builder: (context, value, _) => ...,
);
controller.commits.listen((change) { ... });          // every write (debounce if persisting)

// Lifecycle
controller.dispose();                                 // mandatory

---

Bidirectional sync (Storybook-args pattern)

The real payoff of the controller is that any widget — not just the panel — can bind to the same notifiers. Rendered preview components become participants in the shared state: the user can toggle a switch inside the live preview and the panel's corresponding row flips to match.

// The panel binds 'enabled' to its switch row automatically.
DynamicPropertiesPanel(controller: controller, properties: ...)

// Your preview component reads and writes the same state.
Widget previewSwitch(DynamicPropertiesController ctrl) {
  final on = ctrl['enabled'] as bool? ?? false;
  return ReboundSwitch(
    value: on,
    onChanged: (next) => ctrl['enabled'] = next, // panel's row flips to match
  );
}

---

Persistence — debounce in your handler

Every write fires listeners and the commits stream, including on every drag tick. Hosts that persist should debounce in their own handler:

Timer? saveTimer;
controller.commits.listen((_) {
  saveTimer?.cancel();
  saveTimer = Timer(const Duration(milliseconds: 300), () {
    saveToDisk(controller.snapshot());
  });
});

Granular rebuilds inside the panel mean the drag-tick firehose is cheap to observe — only the affected row rebuilds, not the whole panel or host.

---

Three listener tiers

Mechanism	Scope	Best for
controller.notifierFor(key)	one property	per-field rebuilds in preview components
controller.addListener(...) / ListenableBuilder(listenable: controller)	all properties	live JSON display, debug panels, component preview
controller.commits.listen(...)	all writes, as PropertyChange events	save-to-disk (with debounce), analytics

Pick the tier that matches how expensive your consumer is.

---

Presets

Preset toolbars (save / reset / delete) are built in. Pass presets, onPresetSelected, and onPresetsChanged on the panel — those work the same in both controller and Map-based modes. Nested component presets use componentPresets / onComponentPresetsChanged.

---

Property Types And Flutter Mapping

Use type in your schema to select a control. DynamicPropertyDefinition.inferKind maps these strings to DynamicPropertyKind.

Core types

Schema type	Kind	Stored value format	Flutter mapping
String	string	String	String properties
int / integer	integer	int	numeric integer props
double / num / number	double	double	numeric double props
bool / boolean	boolean	bool	toggle/boolean props
any type + enumValues	enumValue	selected enum item	enum-like props (stored as listed value)
any type + enumValues + multiSelect: true	multiEnum	List<dynamic>	multi-select enum props
object or properties	object	Map<String,dynamic>	nested config objects
List<...> / array / list	array	List<dynamic>	list props
Map<...> / map	map	Map<String,dynamic>	key/value map props
json / dynamic	json	any JSON-serializable value	raw fallback editor

Flutter convenience types

Schema type	Kind	Stored value format	Flutter mapping
Color	color	#RRGGBB or #AARRGGBB	Color
Color.swatch / ColorSwatch	colorSwatch	#RRGGBB	Color
icon / IconData	icon	icon name String	IconData via registry/picker
Icon.swatch / IconSwatch	iconSwatch	icon name String	IconData via swatch picker
date / DateTime	date	ISO-8601 String	DateTime
Duration / duration	duration	int milliseconds	Duration
Slider	slider	double	double range values
Alignment / AlignmentGeometry	alignment	{x: double, y: double}	Alignment
EdgeInsets / EdgeInsetsGeometry	edgeInsets	{top,right,bottom,left}	EdgeInsets
BorderRadius / BorderRadiusGeometry	borderRadius	{topLeft,topRight,bottomLeft,bottomRight}	BorderRadius
BoxConstraints	boxConstraints	{minWidth,maxWidth,minHeight,maxHeight}	BoxConstraints
TextStyle	textStyle	{markdown: String, ...}	TextStyle-adjacent rich text config
MainAxisAlignment	mainAxisAlignment	enum name String (for example start)	MainAxisAlignment
CrossAxisAlignment	crossAxisAlignment	enum name String	CrossAxisAlignment
MainAxisSize	mainAxisSize	enum name String	MainAxisSize
Axis	axis	enum name String	Axis
TextAlign	textAlign	enum name String	TextAlign
Size	size	{width: double?, height: double?}	Size
Rotation	rotation	double degrees	rotation angle props

Widget slots

Schema type	Kind	Stored value format
Widget	widget	{componentId: String, config: Map<String,dynamic>} or null
List<Widget>	widgetList	List<{componentId, config}?>

Example schema

final properties = DynamicPropertyDefinition.listFromJson([
  {'name': 'title', 'type': 'String'},
  {'name': 'themeColor', 'type': 'Color'},
  {'name': 'padding', 'type': 'EdgeInsets'},
  {'name': 'layout', 'type': 'object', 'properties': {'radius': {'type': 'double'}}},
  {'name': 'child', 'type': 'Widget'},
]);

---

Example

See /example for a complete app with:

• Nested object editing
• Map editing
• Widget and widget-list slot editing
• Live JSON preview (via ListenableBuilder)
• Interactive preview with bidirectional switch + slider
• Preset save/restore
• Widget-slot picker with child component config

Run it with flutter run from the /example directory.