Fixes to follows listing

src/state/models/user-follows-view.ts

@@ -1,13 +1,13 @@
 import {makeAutoObservable} from 'mobx'
 import {
-  AppBskyGraphGetFollows as GetFollows,
+  AppBskyGraphGetFollowers as GetFollows,
   AppBskyActorRef as ActorRef,
 } from '@atproto/api'
 import {RootStoreModel} from './root-store'
 
-export type FollowItem = GetFollows.Follow & {
-  _reactKey: string
-}
+const PAGE_SIZE = 30
+
+export type FollowItem = GetFollows.Follow
 
 export class UserFollowsViewModel {
   // state
@@ -16,6 +16,9 @@ export class UserFollowsViewModel {
   hasLoaded = false
   error = ''
   params: GetFollows.QueryParams
+  hasMore = true
+  loadMoreCursor?: string
+  private _loadMorePromise: Promise<void> | undefined
 
   // data
   subject: ActorRef.WithInfo = {
@@ -55,16 +58,17 @@ export class UserFollowsViewModel {
   // public api
   // =
 
-  async setup() {
-    await this._fetch()
-  }
-
   async refresh() {
-    await this._fetch(true)
+    return this.loadMore(true)
   }
 
-  async loadMore() {
-    // TODO
+  async loadMore(isRefreshing = false) {
+    if (this._loadMorePromise) {
+      return this._loadMorePromise
+    }
+    this._loadMorePromise = this._loadMore(isRefreshing)
+    await this._loadMorePromise
+    this._loadMorePromise = undefined
   }
 
   // state transitions
@@ -89,32 +93,30 @@ export class UserFollowsViewModel {
   // loader functions
   // =
 
-  private async _fetch(isRefreshing = false) {
+  private async _loadMore(isRefreshing = false) {
+    if (!this.hasMore) {
+      return
+    }
     this._xLoading(isRefreshing)
     try {
-      const res = await this.rootStore.api.app.bsky.graph.getFollows(
-        this.params,
-      )
-      this._replaceAll(res)
+      const params = Object.assign({}, this.params, {
+        limit: PAGE_SIZE,
+        before: this.loadMoreCursor,
+      })
+      if (this.isRefreshing) {
+        this.follows = []
+      }
+      const res = await this.rootStore.api.app.bsky.graph.getFollows(params)
+      await this._appendAll(res)
       this._xIdle()
     } catch (e: any) {
-      this._xIdle(`Failed to load feed: ${e.toString()}`)
+      this._xIdle(e)
     }
   }
 
-  private _replaceAll(res: GetFollows.Response) {
-    this.subject.did = res.data.subject.did
-    this.subject.handle = res.data.subject.handle
-    this.subject.displayName = res.data.subject.displayName
-    this.subject.avatar = res.data.subject.avatar
-    this.follows.length = 0
-    let counter = 0
-    for (const item of res.data.follows) {
-      this._append({_reactKey: `item-${counter++}`, ...item})
-    }
-  }
-
-  private _append(item: FollowItem) {
-    this.follows.push(item)
+  private async _appendAll(res: GetFollows.Response) {
+    this.loadMoreCursor = res.data.cursor
+    this.hasMore = !!this.loadMoreCursor
+    this.follows = this.follows.concat(res.data.follows)
   }
 }

src/view/com/profile/ProfileFollows.tsx

@@ -5,11 +5,11 @@ import {
   UserFollowsViewModel,
   FollowItem,
 } from '../../../state/models/user-follows-view'
-import {useStores} from '../../../state'
 import {Link} from '../util/Link'
 import {Text} from '../util/text/Text'
 import {ErrorMessage} from '../util/error/ErrorMessage'
 import {UserAvatar} from '../util/UserAvatar'
+import {useStores} from '../../../state'
 import {s} from '../../lib/styles'
 import {usePalette} from '../../lib/hooks/usePalette'
 
@@ -19,30 +19,29 @@ export const ProfileFollows = observer(function ProfileFollows({
   name: string
 }) {
   const store = useStores()
-  const [view, setView] = React.useState<UserFollowsViewModel | undefined>()
+  const view = React.useMemo(
+    () => new UserFollowsViewModel(store, {user: name}),
+    [store, name],
+  )
 
   useEffect(() => {
-    if (view?.params.user === name) {
-      return // no change needed? or trigger refresh?
-    }
-    const newView = new UserFollowsViewModel(store, {user: name})
-    setView(newView)
-    newView
-      .setup()
+    view
+      .loadMore()
       .catch(err => store.log.error('Failed to fetch user follows', err))
-  }, [name, view?.params.user, store])
+  }, [view, store.log])
 
   const onRefresh = () => {
-    view?.refresh()
+    view.refresh()
+  }
+  const onEndReached = () => {
+    view
+      .loadMore()
+      .catch(err =>
+        view?.rootStore.log.error('Failed to load more follows', err),
+      )
   }
 
-  // loading
-  // =
-  if (
-    !view ||
-    (view.isLoading && !view.isRefreshing) ||
-    view.params.user !== name
-  ) {
+  if (!view.hasLoaded) {
     return (
       <View>
         <ActivityIndicator />
@@ -66,16 +65,25 @@ export const ProfileFollows = observer(function ProfileFollows({
 
   // loaded
   // =
-  const renderItem = ({item}: {item: FollowItem}) => <User item={item} />
+  const renderItem = ({item}: {item: FollowItem}) => (
+    <User key={item.did} item={item} />
+  )
   return (
-    <View>
     <FlatList
       data={view.follows}
-        keyExtractor={item => item._reactKey}
+      keyExtractor={item => item.did}
+      refreshing={view.isRefreshing}
+      onRefresh={onRefresh}
+      onEndReached={onEndReached}
       renderItem={renderItem}
-        contentContainerStyle={{paddingBottom: 200}}
-      />
+      initialNumToRender={15}
+      ListFooterComponent={() => (
+        <View style={styles.footer}>
+          {view.isLoading && <ActivityIndicator />}
         </View>
+      )}
+      extraData={view.isLoading}
+    />
   )
 })
 
@@ -100,7 +108,7 @@ const User = ({item}: {item: FollowItem}) => {
           <Text style={[s.bold, pal.text]}>
             {item.displayName || item.handle}
           </Text>
-          <Text type="sm" style={pal.textLight}>
+          <Text type="sm" style={[pal.textLight]}>
             @{item.handle}
           </Text>
         </View>
@@ -122,16 +130,14 @@ const styles = StyleSheet.create({
     paddingTop: 10,
     paddingBottom: 10,
   },
-  avi: {
-    width: 40,
-    height: 40,
-    borderRadius: 20,
-    resizeMode: 'cover',
-  },
   layoutContent: {
     flex: 1,
     paddingRight: 10,
     paddingTop: 10,
     paddingBottom: 10,
   },
+  footer: {
+    height: 200,
+    paddingTop: 20,
+  },
 })