8.9 KiB
8.9 KiB
Avatar System Usage Examples
This document provides practical examples of how to use the avatar fetching system in your components.
Basic Usage
Simple Avatar Display
import Avatar from './components/Avatar.jsx'
function UserProfile({ user }) {
return (
<div className="user-profile">
<Avatar
handle={user.handle}
did={user.did}
size={80}
alt={`${user.displayName}'s avatar`}
/>
<h3>{user.displayName}</h3>
</div>
)
}
Avatar from Record Data
function CommentItem({ record }) {
return (
<div className="comment">
<Avatar
record={record}
size={40}
showFallback={true}
/>
<div className="comment-content">
<strong>{record.value.author.displayName}</strong>
<p>{record.value.text}</p>
</div>
</div>
)
}
Avatar with Hover Card
import { AvatarWithCard } from './components/Avatar.jsx'
function UserList({ users, apiConfig }) {
return (
<div className="user-list">
{users.map(user => (
<AvatarWithCard
key={user.handle}
handle={user.handle}
did={user.did}
displayName={user.displayName}
apiConfig={apiConfig}
size={50}
/>
))}
</div>
)
}
Advanced Usage
Programmatic Avatar Fetching
import { useEffect, useState } from 'react'
import { getAvatar, batchFetchAvatars } from './utils/avatar.js'
function useUserAvatars(users) {
const [avatars, setAvatars] = useState(new Map())
const [loading, setLoading] = useState(false)
useEffect(() => {
async function fetchAvatars() {
setLoading(true)
try {
const avatarMap = await batchFetchAvatars(users)
setAvatars(avatarMap)
} catch (error) {
console.error('Failed to fetch avatars:', error)
} finally {
setLoading(false)
}
}
if (users.length > 0) {
fetchAvatars()
}
}, [users])
return { avatars, loading }
}
// Usage
function TeamDisplay({ team }) {
const { avatars, loading } = useUserAvatars(team.members)
if (loading) return <div>Loading team...</div>
return (
<div className="team">
{team.members.map(member => (
<img
key={member.handle}
src={avatars.get(member.handle) || '/default-avatar.png'}
alt={member.displayName}
/>
))}
</div>
)
}
Force Refresh Avatar
import { useState } from 'react'
import Avatar from './components/Avatar.jsx'
import { getAvatar, clearAvatarCache } from './utils/avatar.js'
function RefreshableAvatar({ handle, did }) {
const [key, setKey] = useState(0)
const handleRefresh = async () => {
// Clear cache for this user
clearAvatarCache(handle)
// Force re-render of Avatar component
setKey(prev => prev + 1)
// Optionally, prefetch fresh avatar
try {
await getAvatar({ handle, did, forceFresh: true })
} catch (error) {
console.error('Failed to refresh avatar:', error)
}
}
return (
<div className="refreshable-avatar">
<Avatar
key={key}
handle={handle}
did={did}
size={60}
/>
<button onClick={handleRefresh}>
Refresh Avatar
</button>
</div>
)
}
Avatar List with Overflow
import { AvatarList } from './components/Avatar.jsx'
function ParticipantsList({ participants, maxVisible = 5 }) {
return (
<div className="participants">
<h4>Participants ({participants.length})</h4>
<AvatarList
users={participants}
maxDisplay={maxVisible}
size={32}
/>
{participants.length > maxVisible && (
<span className="overflow-text">
and {participants.length - maxVisible} more...
</span>
)}
</div>
)
}
Error Handling
Custom Error Handling
import { useState } from 'react'
import Avatar from './components/Avatar.jsx'
function RobustAvatar({ handle, did, fallbackSrc }) {
const [hasError, setHasError] = useState(false)
const handleError = (error) => {
console.warn(`Avatar failed for ${handle}:`, error)
setHasError(true)
}
if (hasError && fallbackSrc) {
return (
<img
src={fallbackSrc}
alt="Fallback avatar"
className="avatar"
onError={() => setHasError(false)} // Reset on fallback error
/>
)
}
return (
<Avatar
handle={handle}
did={did}
onError={handleError}
showFallback={!hasError}
/>
)
}
Loading States
import { useState, useEffect } from 'react'
import { getAvatar } from './utils/avatar.js'
function AvatarWithCustomLoading({ handle, did }) {
const [avatar, setAvatar] = useState(null)
const [loading, setLoading] = useState(true)
const [error, setError] = useState(null)
useEffect(() => {
async function loadAvatar() {
try {
setLoading(true)
setError(null)
const avatarUrl = await getAvatar({ handle, did })
setAvatar(avatarUrl)
} catch (err) {
setError(err.message)
} finally {
setLoading(false)
}
}
loadAvatar()
}, [handle, did])
if (loading) {
return <div className="avatar-loading-spinner">Loading...</div>
}
if (error) {
return <div className="avatar-error">Failed to load avatar</div>
}
if (!avatar) {
return <div className="avatar-placeholder">No avatar</div>
}
return <img src={avatar} alt="Avatar" className="avatar" />
}
Optimization Patterns
Preloading Strategy
import { useEffect } from 'react'
import { prefetchAvatar } from './utils/avatar.js'
function UserCard({ user, isVisible }) {
// Preload avatar when component becomes visible
useEffect(() => {
if (isVisible && user.handle) {
prefetchAvatar(user.handle)
}
}, [isVisible, user.handle])
return (
<div className="user-card">
{isVisible && (
<Avatar handle={user.handle} did={user.did} />
)}
<h4>{user.displayName}</h4>
</div>
)
}
Lazy Loading with Intersection Observer
import { useState, useEffect, useRef } from 'react'
import Avatar from './components/Avatar.jsx'
function LazyAvatar({ handle, did, ...props }) {
const [isVisible, setIsVisible] = useState(false)
const ref = useRef()
useEffect(() => {
const observer = new IntersectionObserver(
([entry]) => {
if (entry.isIntersecting) {
setIsVisible(true)
observer.disconnect()
}
},
{ threshold: 0.1 }
)
if (ref.current) {
observer.observe(ref.current)
}
return () => observer.disconnect()
}, [])
return (
<div ref={ref}>
{isVisible ? (
<Avatar handle={handle} did={did} {...props} />
) : (
<div className="avatar-placeholder" style={{
width: props.size || 40,
height: props.size || 40
}} />
)}
</div>
)
}
Cache Management
Cache Statistics Display
import { useEffect, useState } from 'react'
import { getAvatarCacheStats, cleanupExpiredAvatars } from './utils/avatarCache.js'
function CacheStatsPanel() {
const [stats, setStats] = useState(null)
useEffect(() => {
const updateStats = () => {
setStats(getAvatarCacheStats())
}
updateStats()
const interval = setInterval(updateStats, 5000) // Update every 5 seconds
return () => clearInterval(interval)
}, [])
const handleCleanup = async () => {
const cleaned = cleanupExpiredAvatars()
alert(`Cleaned ${cleaned} expired cache entries`)
setStats(getAvatarCacheStats())
}
if (!stats) return null
return (
<div className="cache-stats">
<h4>Avatar Cache Stats</h4>
<p>Cached avatars: {stats.totalCached}</p>
<p>Cache hit rate: {stats.hitRate}%</p>
<p>Cache hits: {stats.cacheHits}</p>
<p>Cache misses: {stats.cacheMisses}</p>
<button onClick={handleCleanup}>
Clean Expired Cache
</button>
</div>
)
}
Testing Helpers
Mock Avatar for Testing
// For testing environments
const MockAvatar = ({ handle, size = 40, showFallback = true }) => {
if (!showFallback) return null
const initial = (handle || 'U')[0].toUpperCase()
return (
<div
className="avatar-mock"
style={{
width: size,
height: size,
borderRadius: '50%',
backgroundColor: '#e1e1e1',
display: 'flex',
alignItems: 'center',
justifyContent: 'center',
fontSize: size * 0.4,
color: '#666'
}}
>
{initial}
</div>
)
}
// Use in tests
export default process.env.NODE_ENV === 'test' ? MockAvatar : Avatar
These examples demonstrate the flexibility and power of the avatar system while maintaining good performance and user experience practices.