我是本机反应的初学者,我正在尝试开发购物应用程序。当我尝试从db firebase读取客户订单时,无法到达产品,并且显示未定义。
这是我的代码
export default class Orders extends React.Component {
constructor(props) {
super(props);
this.state = {
arrData:[]
};
}
componentDidMount = () => {
var ref = database.ref('orders');
ref.once('value').then(snapshot => {
console.log('Orders',snapshot.val());
// get children as an array
var items = [];
snapshot.forEach((child) => {
items.push({
id: child.val().id,
customer: child.val().customerId,
products:JSON.stringify([child.val().products]),
});
});
this.setState({ arrData: items});
//console.log(items);
});
}
renderItem = ({item, index}) => (
<TouchableOpacity
style={styles.listItem}>
<View style={styles.view}>
<Text style={styles.text}>{item.customer}</Text>
</View>
</TouchableOpacity>
)
render()
{
return(
<View style={{flex: 1}}>
<FlatList
//refreshing={this.state.refresh}
//onRefresh={this.loadNew}
data={this.state.arrData}
keyExtractor={(item, index) => index.toString()}
style={{flex:1, backgroundColor:'#eee'}}
renderItem={this.renderItem}
//onEndReached={this.handleLoadMore}
onEndThreshold={0}
/>
</View>
)
}
}
我试图更改此行
var ref = database.ref('orders');
进入此
var ref = database.ref('orders').child(myOrders);
但是我在控制台中得到了(空)