message: Added keyExtractor to FlatList
diff: @@ -187,6 +187,7 @@ class PickerNB extends Component {
  <Content>
  <FlatList
  data={this.state.dataSource}
  + keyExtractor={(item, index) => index}
  renderItem={({ item }) => <ListItem
  selected={item.props.value === this.props.selectedValue}
  button
  