about summary refs log tree commit diff
path: root/src/view/com/posts/Feed.tsx
blob: 5751faa68b3bf5b3c4e4b4b83341a8b054f9da74 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
import React, {MutableRefObject} from 'react'
import {observer} from 'mobx-react-lite'
import {
  ActivityIndicator,
  View,
  StyleProp,
  StyleSheet,
  ViewStyle,
} from 'react-native'
import {FontAwesomeIcon} from '@fortawesome/react-native-fontawesome'
import {FontAwesomeIconStyle} from '@fortawesome/react-native-fontawesome'
import {CenteredView, FlatList} from '../util/Views'
import {PostFeedLoadingPlaceholder} from '../util/LoadingPlaceholder'
import {Text} from '../util/text/Text'
import {ErrorMessage} from '../util/error/ErrorMessage'
import {Button} from '../util/forms/Button'
import {FeedModel} from 'state/models/feed-view'
import {FeedItem} from './FeedItem'
import {OnScrollCb} from 'lib/hooks/useOnMainScroll'
import {s} from 'lib/styles'
import {useStores} from 'state/index'
import {useAnalytics} from 'lib/analytics'
import {usePalette} from 'lib/hooks/usePalette'
import {MagnifyingGlassIcon} from 'lib/icons'

const EMPTY_FEED_ITEM = {_reactKey: '__empty__'}
const ERROR_FEED_ITEM = {_reactKey: '__error__'}

export const Feed = observer(function Feed({
  feed,
  style,
  showPostFollowBtn,
  scrollElRef,
  onPressTryAgain,
  onScroll,
  testID,
  headerOffset = 0,
}: {
  feed: FeedModel
  style?: StyleProp<ViewStyle>
  showPostFollowBtn?: boolean
  scrollElRef?: MutableRefObject<FlatList<any> | null>
  onPressTryAgain?: () => void
  onScroll?: OnScrollCb
  testID?: string
  headerOffset?: number
}) {
  const pal = usePalette('default')
  const palInverted = usePalette('inverted')
  const store = useStores()
  const {track} = useAnalytics()
  const [isRefreshing, setIsRefreshing] = React.useState(false)

  const data = React.useMemo(() => {
    let feedItems: any[] = []
    if (feed.hasLoaded) {
      if (feed.hasError) {
        feedItems = feedItems.concat([ERROR_FEED_ITEM])
      }
      if (feed.isEmpty) {
        feedItems = feedItems.concat([EMPTY_FEED_ITEM])
      } else {
        feedItems = feedItems.concat(feed.nonReplyFeed)
      }
    }
    return feedItems
  }, [feed.hasError, feed.hasLoaded, feed.isEmpty, feed.nonReplyFeed])

  // events
  // =

  const onRefresh = React.useCallback(async () => {
    track('Feed:onRefresh')
    setIsRefreshing(true)
    try {
      await feed.refresh()
    } catch (err) {
      feed.rootStore.log.error('Failed to refresh posts feed', err)
    }
    setIsRefreshing(false)
  }, [feed, track, setIsRefreshing])
  const onEndReached = React.useCallback(async () => {
    track('Feed:onEndReached')
    try {
      await feed.loadMore()
    } catch (err) {
      feed.rootStore.log.error('Failed to load more posts', err)
    }
  }, [feed, track])

  // rendering
  // =

  // TODO optimize renderItem or FeedItem, we're getting this notice from RN: -prf
  //   VirtualizedList: You have a large list that is slow to update - make sure your
  //   renderItem function renders components that follow React performance best practices
  //   like PureComponent, shouldComponentUpdate, etc
  const renderItem = React.useCallback(
    ({item}: {item: any}) => {
      if (item === EMPTY_FEED_ITEM) {
        return (
          <View style={styles.emptyContainer}>
            <View style={styles.emptyIconContainer}>
              <MagnifyingGlassIcon
                style={[styles.emptyIcon, pal.text]}
                size={62}
              />
            </View>
            <Text type="xl-medium" style={[s.textCenter, pal.text]}>
              Your feed is empty! You should follow some accounts to fix this.
            </Text>
            <Button
              type="inverted"
              style={styles.emptyBtn}
              onPress={() => store.nav.navigate('/search')}>
              <Text type="lg-medium" style={palInverted.text}>
                Find accounts
              </Text>
              <FontAwesomeIcon
                icon="angle-right"
                style={palInverted.text as FontAwesomeIconStyle}
                size={14}
              />
            </Button>
          </View>
        )
      } else if (item === ERROR_FEED_ITEM) {
        return (
          <ErrorMessage
            message={feed.error}
            onPressTryAgain={onPressTryAgain}
          />
        )
      }
      return <FeedItem item={item} showFollowBtn={showPostFollowBtn} />
    },
    [feed, onPressTryAgain, showPostFollowBtn, pal, palInverted, store.nav],
  )

  const FeedFooter = React.useCallback(
    () =>
      feed.isLoading ? (
        <View style={styles.feedFooter}>
          <ActivityIndicator />
        </View>
      ) : (
        <View />
      ),
    [feed],
  )

  return (
    <View testID={testID} style={style}>
      {feed.isLoading && data.length === 0 && (
        <CenteredView style={{paddingTop: headerOffset}}>
          <PostFeedLoadingPlaceholder />
        </CenteredView>
      )}
      {data.length > 0 && (
        <FlatList
          ref={scrollElRef}
          data={data}
          keyExtractor={item => item._reactKey}
          renderItem={renderItem}
          ListFooterComponent={FeedFooter}
          refreshing={isRefreshing}
          contentContainerStyle={s.contentContainer}
          onScroll={onScroll}
          onRefresh={onRefresh}
          onEndReached={onEndReached}
          onEndReachedThreshold={0.6}
          removeClippedSubviews={true}
          contentInset={{top: headerOffset}}
          contentOffset={{x: 0, y: headerOffset * -1}}
          progressViewOffset={headerOffset}
        />
      )}
    </View>
  )
})

const styles = StyleSheet.create({
  feedFooter: {paddingTop: 20},
  emptyContainer: {
    paddingVertical: 40,
    paddingHorizontal: 30,
  },
  emptyIconContainer: {
    marginBottom: 16,
  },
  emptyIcon: {
    marginLeft: 'auto',
    marginRight: 'auto',
  },
  emptyBtn: {
    marginTop: 20,
    flexDirection: 'row',
    alignItems: 'center',
    justifyContent: 'space-between',
  },
})