docs: add fireEvent.scroll example for FlatList

[ajubin]

Summary

When testing scroll on a flatlist, I was getting the error : TypeError: cannot read property 'height' of undefined

Error thrown

Component tested

export class InfiniteScrollFlatList<Item> extends PureComponent<Props<Item>> {
  private handleLoadMore = () => {
    if (!this.props.isLoadingMore && this.props.nextPage) {
      this.props.fetchMore({ page: this.props.nextPage });
    }
  };

  private renderListFooter = () => {
    if (this.props.isLoadingMore) return <Loader />;
    return null;
  };

  public render() {
    return (
      <FlatList
        {...this.props}
        onEndReachedThreshold={0.2}
        onEndReached={this.handleLoadMore}
        ListFooterComponent={this.renderListFooter}
      />
    );
  }
}

Test plan

[thymikee]

Hey! Thanks for sending that. The example though is about ScrollView, not FlatList. Could you verify that the scroll event is the same for scroll view and flat list?

[ajubin]

Hello,

My example here is about FlatList. The contentSize and the layoutMeasurement are not needed for ScrollView. Should I had another example ?

[thymikee]

Please add another example then :) Feel free to only mention the scroll event data differs between components, and e.g. for FlatList it looks like this.

[ajubin]

@thymikee I've updated my pr

[thymikee]

LGTM, thanks!