empty ImmutableVirtualizedList always generates a missing key prop warning

version: 0.6.2

If my ImmutableVirtualizedList is empty, I will see this warning:

ExceptionsManager.js:73 Warning: Each child in an array or iterator should have a unique "key" prop.

Check the render method of `VirtualizedList`. See https://fb.me/react-warning-keys for more information.
    in CellRenderer (at VirtualizedList.js:499)
    in VirtualizedList (at ImmutableVirtualizedList.js:109)
    in ImmutableVirtualizedList (at EmptyVirtualizedList.js:76)
    in EmptyVirtualizedList (at ImmutableVirtualizedList.js:102)
    in ImmutableVirtualizedList (at CpTeamList.js:19)
    in RCTView (at View.js:113)
    in View (at CpTeamList.js:18)
    in CpTeamList (at CtTeamList.js:58)

I’ve tried implementing my own renderEmptyInList that provides a key on the rendered component, but the warning remains.

Code:

 render() {
    return (
      <View style={styles.container}>
        <ImmutableVirtualizedList
          immutableData={List()}
          ItemSeparatorComponent={this.renderSeparator}
          keyExtractor={(item) => item.get("id")}
          /*renderEmptyInList={this.renderEmptyInList}*/
          renderItem={this.renderItem}
        />
      </View>
    )
  }

[Jephuff]

@cooperka I found that it was because the data structure was being overwritten, but the keyExtractor wasn’t. So if you had a keyExtractor like (item) => item.get("id") that wouldn’t exist on the empty data. I fixed it by overriding keyExtractor in the empty list so that it just returns ‘empty’

https://github.com/Jephuff/react-native-immutable-list-view/commit/3c8460e009ca93940ee44050796bf24c287229b1

I can make a PR with that change if you’d like

[cooperka]

Resolved by https://github.com/cooperka/react-native-immutable-list-view/pull/35.