backend_driven_ui 0.2.1

Server-Driven UI framework for Flutter with ApiWidget - build data-driven interfaces without FutureBuilder boilerplate.

Changelog

All notable changes to this project will be documented in this file.

0.2.1 - 2026-04-14

Fixed

• Restored example/ in the published archive so pub.dev awards the example pub points (was incorrectly excluded in 0.2.0 .pubignore)
• Added missing dartdoc comments to ActionHandler constructor and fields (context, onApiSuccess, onApiError, onCustomAction)

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0.2.0 - 2026-04-13

Added

• BduiConfig.baseUrl — set a global base URL once; all relative endpoints resolve against it automatically
• SchemaParser.register() — convenience method to add custom widget builders without accessing the registry directly
• Named color support in JSON: "color": "blue", "color": "Colors.deepPurple", "color": "#1976D2" (all Flutter color names + CSS hex + ARGB hex — any format now works)
• onLaunchUrl callback on ActionHandler, SchemaParser, and BackendDrivenScreen — wire in url_launcher or any custom handler to handle launchUrl actions from JSON schemas
• 74 tests covering ApiCache, WidgetSchema, BduiConfig, helpers, ApiClient, SchemaWidget, and custom widget registration

Fixed

• WidgetRegistry.instance referenced in README docs was incorrect — corrected to use SchemaParser.register() API
• Cache key generation now uses a deterministic polynomial hash and sorted props keys — previously XOR-based hashing caused collisions for schemas with swapped or duplicate children
• ApiClient.dispose() now guards against _performDisposal() being called more than once when multiple in-flight requests complete simultaneously
• JSON response unwrapping for ui/data keys now validates the value is a Map before extracting — previously a non-Map value (e.g. String) would propagate and crash the schema parser
• evaluateCondition now logs a warning with the full list of supported conditions when an unknown condition string is received, instead of silently returning false

Changed

• logger.dart renamed to bdui_logger.dart for clarity — internal change, no public API impact

Removed

• "Early stage" disclaimer from README — the API is stable

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0.1.0 - 2025-03-17

Added

ApiWidget

• 🎯 Declarative API data fetching widget (FutureBuilder alternative)
• Built-in loading, success, error, and empty states
• Automatic caching with configurable TTL
• Retry logic with exponential backoff
• Polling support for real-time updates
• Success/error callbacks
• Retry button on errors

Backend-Driven UI

• 🚀 BackendDrivenScreen - Fetch and render UI from JSON schemas
• SchemaParser - Parse JSON into Flutter widgets
• WidgetRegistry - Extensible widget system
• 33 Built-in widgets:
  • Layout (12): Column, Row, Stack, Center, Padding, SizedBox, Expanded, Flexible, Wrap, Spacer, AspectRatio, Container
  • Display (4): Text, Icon, Image, Divider
  • Material (5): Card, ListTile, CircleAvatar, Chip, ClipRRect
  • Interactive (7): Button, ElevatedButton, TextButton, OutlinedButton, IconButton, GestureDetector, InkWell
  • Scrollable (3): ListView, GridView, SingleChildScrollView
  • Effects (2): Visibility, Opacity
• Conditional rendering (platform, screen size, theme detection)
• Widget schema caching for performance

Core Features

• 📦 Lightweight HTTP client (only http package dependency)
• Custom retry handler with exponential backoff
• LRU cache with TTL for API responses
• Server-controlled caching - Backend can specify cache policy per response:
  • cache - Cache with optional TTL
  • noCache - Always fetch fresh
  • refresh - Stale-while-revalidate pattern
• Action handler system (navigate, API calls, dialogs, etc.)
• Type-safe models for requests/responses

Documentation

• 📖 Comprehensive README with examples
• JSON Schema Reference Guide (SCHEMA_REFERENCE.md)
• Working example app with multiple demos
• Inline code documentation

Technical Details

• Zero heavy dependencies (50KB vs 350KB+ with dio)
• Production-ready error handling
• Material Design 3 support
• Platform-agnostic architecture