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[VirtualizedList] - Warning: Each child in an array or iterator should have a unique "key" prop.

See original GitHub issue

Hello, there is a warning in render method of VirtualizedList. Not sure if this is your problem… I wasn’t able to find it in code yet. It may be a problem of one of the dependencies… Can you please look at it? It’s only a warning, but still… 😃

` 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:463) in VirtualizedList (at FlatList.js:557) in FlatList (at Column.js:129) in RCTView (at View.js:113) in View (at Column.js:121) in Column (at Masonry.js:118) in StaticRenderer (at ListView.js:464) in RCTScrollContentView (at ScrollView.js:707) in RCTScrollView (at ScrollView.js:800) in ScrollView (at ListView.js:332) in ListView (at Masonry.js:113) in RCTView (at View.js:113) in View (at Masonry.js:112) in Masonry (at PageGallery.js:13) in PageGallery (at App.js:203) in RCTScrollContentView (at ScrollView.js:707) in RCTScrollView (at ScrollView.js:800) in ScrollView (at KeyboardAwareScrollView.js:27) in KeyboardAwareScrollView (at Content.js:10) in Content (at connectStyle.js:384) in Styled(Content) (at App.js:302) in RCTView (at View.js:113) in View (at Container.js:19) in Container (at connectStyle.js:384) in Styled(Container) (at App.js:252) in RCTView (at View.js:113) in View (at index.js:570) in RCTView (at View.js:113) in View (at index.js:557) in Drawer (at index.js:10) in Drawer (at App.js:234) in RCTView (at View.js:113) in View (at Root.js:14) in Root (at connectStyle.js:384) in Styled(Root) (at App.js:233) in App (at registerRootComponent.js:36) in RootErrorBoundary (at registerRootComponent.js:35) in ExpoRootComponent (at renderApplication.js:35) in RCTView (at View.js:113) in View (at AppContainer.js:100) in RCTView (at View.js:113) in View (at AppContainer.js:121) in AppContainer (at renderApplication.js:34) `

Issue Analytics

State:
Created 6 years ago
Comments:18 (18 by maintainers)

Top GitHub Comments

1reaction

brh55commented, Sep 26, 2017

@soukupl Feel free to PR 😃, also need to do the following:

Bump current package patch number up
Add additional property in readme under brick table to explain key (you can import the table and edit here: http://www.tablesgenerator.com/markdown_tables)

1reaction

brh55commented, Sep 26, 2017

@soukupl I think that solution works well, it’s rather consistent behavior. I don’t see why you should be having any issues with refresh now with: _keyExtractor = item => "IMAGE-KEY-" + item.uri + "---" + (item.data.key ? item.data.key : "0")

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