form_ui_builder library

Dynamic Form UI Builder Library

This library provides a complete solution for building dynamic, data-driven forms in Flutter applications. Forms can be configured via JSON or programmatically and support:

Core Features:

Dynamic field generation from JSON configuration or parameter map
Real-time validation as user types
Conditional field visibility (show/hide based on other field values)
Auto-calculation of dependent fields (e.g., sum, totals)
Multi-field validation (e.g., "field A + field B must equal field C")
Mobile number validation with custom rules
Range validation (min/max values)
Focus management and keyboard navigation

Architecture:

Clean Architecture with separation of concerns
BLoC pattern for state management
Dependency injection via GetIt service locator
Functional programming with Either for error handling (fpdart)

Usage - From JSON (most common):

// 1. Initialize the service locator
setupServiceLocator();

// 2. Build form logic bundle from JSON
final result = buildFormLogicBundle(jsonFormData);

// 3. Use in your UI with FormUiBuilderBloc
BlocProvider(
  create: (_) => FormUiBuilderBloc(
    buildFormLogicBundle: getIt(),
    validateTextFieldValue: getIt(),
    // ... other dependencies
  ),
  child: FormUiBuilderScreen(),
)

Usage - From Parameter Map (advanced):

// 1. Initialize the service locator
setupServiceLocator();

// 2. Create or obtain your parameter map
final parameterMap = <int, ChildrenX>{
  1: ChildrenX(elementId: 1, elementType: 'ElementText', ...),
  2: ChildrenX(elementId: 2, elementType: 'ElementDate', ...),
};

// 3. Build form logic bundle from parameter map
final result = buildFormLogicBundleFromParameterMap(parameterMap);

// 4. Use same as JSON approach

Key Concepts:

FormLogicBundle: Central data structure holding all form state including field configurations, values, visibility states, and dependency relationships.

Dependent Fields: Fields whose values must satisfy constraints based on other fields. Example: "Child fields 10, 11, 12 must sum to parent field 5".

Auto-Calculation: Automatically compute field values from other fields. Example: "Field 20 = Field 15 + Field 16 + Field 17".

Conditional Visibility: Show/hide fields based on selections in other fields. Example: "Show field 14 only when field 13 equals option 1".

form_ui_builder library

Classes

Enums

Properties

Functions

form_ui_builder package

form_ui_builder library