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import { Component } from 'react';
import { withApollo, graphql, compose } from 'react-apollo';
import styled from 'styled-components';
import Pagination from './Pagination';
import Item from './Item';
import { ALL_ITEMS_QUERY, DELETE_ITEM_MUTATION } from '../queries';
const Title = styled.h1`font-size: 10px;`;
const Items = styled.div`
display: grid;
grid-template-columns: repeat(4, calc(33% - 20px));
grid-gap: 20px;
`;
class ItemList extends Component {
componentDidMount() {
this.prefetchNextItems(this.props.page);
}
componentWillReceiveProps(nextProps) {
// update the next items if the page prop changed
if (this.props.page !== nextProps.page) {
this.prefetchNextItems(nextProps.page);
}
}
prefetchNextItems = currentPage => {
const page = currentPage + 1;
console.log(`Prefetching Next items! Page ${page}`);
this.props.client.query({
query: ALL_ITEMS_QUERY,
variables: {
skip: page * 3 - 3,
},
});
};
render() {
// 1
if (this.props.allItemsQuery && this.props.allItemsQuery.loading) {
return <div>Loading</div>;
}
// 2
if (this.props.allItemsQuery && this.props.allItemsQuery.error) {
console.log(this.props.allItemsQuery.error);
return <div>Error</div>;
}
// 3
const itemsToRender = this.props.allItemsQuery.allItems;
return (
<div>
<Pagination page={this.props.page} />
<Title>Items For Sale</Title>
<Items key={this.props.page}>{itemsToRender.map((item, i) => <Item key={item.id} item={item} />)}</Items>
</div>
);
}
}
// 1
// We export the graphQL HOC - this will fetch the data and inject it into the ItemList compeont via props
// Create some Enhancers
const itemEnhancer = graphql(ALL_ITEMS_QUERY, {
name: 'allItemsQuery',
options({ page }) {
return {
variables: {
skip: page * 3 - 3,
},
};
},
});
const deleteItemEnhancer = graphql(DELETE_ITEM_MUTATION, {
name: 'removeItemMutation',
options: {
update: (proxy, { data: { deleteItem } }) => {
// grab the data from our cache
const data = proxy.readQuery({ query: ALL_ITEMS_QUERY });
// filter out the deleted item
data.allItems = data.allItems.filter(item => item.id !== deleteItem.id);
// and then "set state" (update cache), so it will update wherever we have used this data on the page
proxy.writeQuery({ query: ALL_ITEMS_QUERY, data });
},
},
});
export default withApollo(compose(itemEnhancer, deleteItemEnhancer)(ItemList));
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