angular-ui-patterns

name	angular-ui-patterns
description	Angular 21.x UI/UX state patterns — loading states (show only when no data), error hierarchy (inline→toast→banner→full-screen), empty states, button loading, form patterns with validation, dialog/modal patterns. Load when building any Angular UI component that handles async data or user actions.
allowed-tools	Read, Edit, Write, Glob, Grep, Bash, WebFetch, mcp__context7__resolve-library-id, mcp__context7__query-docs
metadata	{"triggers":"Angular loading state, Angular error state, Angular empty state, Angular skeleton, Angular spinner, Angular form validation, Angular button loading, Angular dialog, Angular async UI, Angular UX patterns","related-skills":"angular-spa, angular, angular-best-practices","domain":"frontend","role":"specialist","scope":"implementation","output-format":"code"}
last-reviewed	2026-03-15

Iron Law

LOAD angular-spa FIRST for daisyUI component classes and TailwindCSS 4.x tokens. This skill provides UI state doctrine — use angular-spa reference files for the actual component HTML/CSS.

When to Use This Skill

Load this skill when:

• Building any Angular component that fetches async data
• Adding loading, error, or empty states to a list or page
• Implementing form validation with inline field errors
• Adding button loading states or disabling during async operations
• Building confirmation dialogs or modals
• Reviewing a component for missing UI state coverage

Five Non-Negotiable Principles

1. Never show stale UI — Loading states only when actually loading, never over existing data
2. Always surface errors — Users must know when something fails; never swallow silently
3. Optimistic updates — Make the UI feel instant; roll back on failure
4. Progressive disclosure — Use @defer to show content as available
5. Graceful degradation — Partial data is better than no data

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Pattern Selector

What are you building?

• Async list/page → load reference/loading-control-flow.md
• Error handling → load reference/error-handling.md
• Button with loading → load reference/button-empty-states.md
• Form with validation → load reference/form-dialog-patterns.md
• Reviewing for mistakes → load reference/anti-patterns.md

Reference Files

Reference	Load When
reference/index.md	Any time — navigation
reference/loading-control-flow.md	Building async list or page
reference/error-handling.md	Adding error handling
reference/button-empty-states.md	Buttons or collections
reference/form-dialog-patterns.md	Forms or confirmation dialogs
reference/anti-patterns.md	Reviewing a component

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UI State Checklist

Before completing any UI component:

UI States

• Error state handled and shown to user
• Loading state shown only when no data exists
• Empty state provided for collections (@empty block)
• Buttons disabled during async operations
• Buttons show loading indicator when appropriate

Data & Mutations

• All async operations have error handling
• All user actions have feedback (toast/visual)
• Optimistic updates rollback on failure

Accessibility

• Loading states announced to screen readers
• Error messages linked to form fields
• Focus management after state changes

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daisyUI Integration

This skill provides the doctrine. Use these daisyUI classes from angular-spa skill:

• Loading: class="loading loading-spinner loading-lg"
• Alert: class="alert alert-error" / class="alert alert-success"
• Button loading: class="btn btn-primary loading"
• Skeleton: class="skeleton h-4 w-full"
• Empty state: class="hero min-h-32"

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Related Skills

• angular-spa — workspace skill: daisyUI components, TailwindCSS tokens, conventions
• angular — core API reference for signals and control flow
• angular-best-practices — performance rules that complement these UI patterns