Object {
  "44": Object {
    "pro_id": "44",
    "pro_img": "url",
    "pro_name": " S4 ",
  },
  "52": Object {
    "pro_id": "52",
    "pro_img": "url",
    "pro_name": " S4 ",

  },
}

retrieveData = async () => {
    try {
       await AsyncStorage.getItem('userFavorites') .then(req => JSON.parse(req))
      .then(json =>
        this.setState({
          favPro:json
        })

        )


    } catch (error) {

    } }



 fav = ({ item }) => {
    return (
      <View>
      <Text>{item.pro_id+ item.pro_name}</Text>
      </View>
    )
}

<FlatList
          data={this.state.favPro}
          renderItem={this.fav}
          keyExtractor={item => item.pro_id}
        />