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empty ImmutableVirtualizedList always generates a missing key prop warning

See original GitHub issue

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 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.


 render() {
    return (
      <View style={styles.container}>
          keyExtractor={(item) => item.get("id")}

Issue Analytics

  • State:closed
  • Created 6 years ago
  • Comments:5 (4 by maintainers)

github_iconTop GitHub Comments

Jephuffcommented, May 8, 2018

@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’

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

Read more comments on GitHub >

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