Accessibility

This module provides accessibility enhancements for QR code generation.

Accessibility System

Accessibility enhancement subsystem.

This package provides comprehensive accessibility features for QR code generation, ensuring compliance with accessibility standards and best practices for assistive technologies.

Key Components:

ARIA Support:

Role definitions and management

Label and description generation

Live region support

ID Management:

Stable, predictable ID generation

Configurable prefixes and schemes

Conflict resolution

Screen Reader Optimization:

Semantic SVG structure

Alternative text generation

Content description

Keyboard Navigation:

Focus management

Tab order optimization

Keyboard shortcuts

The accessibility subsystem handles:

ARIA attribute management
Screen reader compatibility
Keyboard navigation support
ID generation and management
Accessibility validation
WCAG compliance checking
Alternative content generation

Example

Basic accessibility enhancement:

from segnomms.a11y import AccessibilityEnhancer, ARIARole

enhancer = AccessibilityEnhancer(
    id_prefix="qr",
    default_role=ARIARole.IMG
)

# Generate stable IDs
module_id = enhancer.generate_id("module", 5, 3)

# Add ARIA attributes
aria_attrs = enhancer.get_aria_attributes(
    role=ARIARole.GRAPHICS_OBJECT,
    label="QR code module at position 5,3"
)

Accessibility Enhancer

class segnomms.a11y.AccessibilityEnhancer(config)[source]

Bases: object

Enhances SVG elements with comprehensive accessibility features.

Parameters:: config (AccessibilityConfig)

__init__(config)[source]

Parameters:: config (AccessibilityConfig)

enhance_root_element(svg_element, title=None, description=None)[source]

Enhance the root SVG element with accessibility features.

Return type:

ElementAccessibility

Parameters:

svg_element (Element)
title (str | None)
description (str | None)

enhance_module_element(element, row, col, module_type='data')[source]

Enhance a QR module element with accessibility features.

Return type:

ElementAccessibility

Parameters:

element (Any)
row (int)
col (int)
module_type (str)

enhance_pattern_group(group_element, pattern_type, index=0)[source]

Enhance a pattern group (finder, timing, etc.) with accessibility.

Return type:

ElementAccessibility

Parameters:

group_element (Any)
pattern_type (str)
index (int)

create_description_element(parent_element, description, ref_id)[source]

Create a description element and return its ID.

Return type:

str

Parameters:

parent_element (Any)
description (str)
ref_id (str)

generate_accessibility_report()[source]

Generate a report of accessibility features applied.

Return type:: Dict[str, Any]

validate_accessibility(svg_root=None)[source]

Validate accessibility implementation and return issues.

Return type:: List[str]
Parameters:: svg_root (Any | None)

ARIA Roles

class segnomms.a11y.ARIARole(*values)[source]

Bases: str, Enum

Standard ARIA roles for QR code elements.

IMG = 'img'

GRAPHICS_DOCUMENT = 'graphics-document'

GRAPHICS_OBJECT = 'graphics-object'

APPLICATION = 'application'

GROUP = 'group'

PRESENTATION = 'presentation'

Configuration

class segnomms.a11y.AccessibilityConfig(**data)[source]

Bases: BaseModel

Comprehensive accessibility configuration.

Parameters:

enabled (bool)
id_prefix (str)
use_stable_ids (bool)
include_coordinates (bool)
enable_aria (bool)
root_role (ARIARole)
module_role (ARIARole | None)
root_label (str)
root_description (str | None)
include_module_labels (bool)
include_pattern_labels (bool)
optimize_for_screen_readers (bool)
group_similar_elements (bool)
add_structural_markup (bool)
enable_keyboard_navigation (bool)
focus_visible_elements (List[str])
target_compliance (AccessibilityLevel)
custom_attributes (Dict[str, str])

model_config: ClassVar[ConfigDict] = {'extra': 'forbid', 'validate_default': True}: Configuration for the model, should be a dictionary conforming to [ConfigDict][pydantic.config.ConfigDict].

enabled: bool

id_prefix: str

use_stable_ids: bool

include_coordinates: bool

enable_aria: bool

root_role: ARIARole

module_role: Optional[ARIARole]

root_label: str

root_description: Optional[str]

include_module_labels: bool

include_pattern_labels: bool

optimize_for_screen_readers: bool

group_similar_elements: bool

add_structural_markup: bool

enable_keyboard_navigation: bool

focus_visible_elements: List[str]

target_compliance: AccessibilityLevel

custom_attributes: Dict[str, str]

classmethod validate_id_prefix(v)[source]

Validate ID prefix follows HTML standards.

Return type:: str
Parameters:: v (str)

classmethod validate_focus_elements(v)[source]

Validate focus element names.

Return type:: List[str]
Parameters:: v (List[str])

Example Usage

Basic accessibility enhancement:

from segnomms.a11y import AccessibilityEnhancer, ARIARole

enhancer = AccessibilityEnhancer(
    id_prefix="qr",
    default_role=ARIARole.IMG
)

# Generate stable IDs
module_id = enhancer.generate_id("module", 5, 3)

# Add ARIA attributes
aria_attrs = enhancer.get_aria_attributes(
    role=ARIARole.GRAPHICS_OBJECT,
    label="QR code module at position 5,3"
)

Configuration setup:

from segnomms.a11y import AccessibilityConfig

config = AccessibilityConfig(
    enable_aria=True,
    enable_screen_reader=True,
    enable_keyboard_nav=True,
    default_title="Interactive QR Code",
    default_description="Scannable QR code with custom styling"
)