filter_improved.js

const Filter = ({ categories, selectedCategories, toggleCategory }) => (
  <View style={{ flex: 1 }}>
    <FlatList
      data={categories}
      extraData={selectedCategories}
      keyExtractor={i => i.id}
      renderItem={({ item }) => (
        <FilterItem
          category={item}
          isShown={!!selectedCategories.find(sc => sc.id === item.id)}
          key={item.id}
          onClick={toggleCategory}
        />
      )}
    />
  </View>
)