问题描述
我有一个使用本机本身的ScrollView的列表。基本上,我是通过API返回动态创建列表的。
async fetchData(userSearch) {
const {route} = this.props;
const {params} = route;
const {type} = params;
this.setState({
loading: true,});
const responseProcedures = await scheduleResource.getProcedures(userSearch);
this.setState({
procedures: responseProcedures.data,loading: false,});
}
<ScrollView
onScroll={(event) => this.shouldLoadMoreContent(event)}
>
{procedures.map(procedure => (
<ArrowBox key={procedure.id} onPress={() => RootNavigation.navigate('ProcedureDetails',{procedure})}>
<Text bold style={styles.ProcedureTitle}>
{procedure.name}
</Text>
{!!procedure.synonyms.length && (
<>
<Text bold style={styles.ProcedureSynonymTitle}>
Sinônimos
</Text>
<View style={styles.ProcedureSynonymOptionsContainer}>
{procedure.synonyms.map(synonym => <Text style={styles.ProcedureSynonymOption} key={synonym}>{synonym}</Text>)}
</View>
</>
)}
</ArrowBox>
))}
</ScrollView>
问题是我从API加载了整个返回值,并且速度变慢了。
当我到达页面末尾时,我想知道如何动态加载内容并在api中进行新的调用。 Api允许我放置偏移量和限制。
有人可以给我一些例子吗?
谢谢!!!!!
解决方法
基本上,ScrollView并非用于处理动态数据,设计用于执行此功能的正确组件称为Flatlist。它的工作原理几乎与ScrollView完全一样,但是速度更快,并且仅呈现屏幕上显示的组件。
请像这样从React Native导入Flatlist ...
//At the top of your file,please import FlatList together with all the modules that you want
import { FlatList,Text,View } from "react-native";
然后用如下所示的Flatlist替换代码中的整个ScrollView:
<FlatList
keyExtractor={(procedure) => procedure.id}
data={this.state.procedures}
renderItem={(procedure) => {
return (
<ArrowBox
key={procedure.id}
onPress={() =>
RootNavigation.navigate("ProcedureDetails",{
procedure })}>
<Text bold style={styles.ProcedureTitle}>
{procedure.name}
</Text>
{!!procedure.synonyms.length && (
<>
<Text bold style={styles.ProcedureSynonymTitle}>
Sinônimos
</Text>
<View
style={styles.ProcedureSynonymOptionsContainer}>
{procedure.synonyms.map((synonym) => (
<Text
style={styles.ProcedureSynonymOption}
key={synonym}>
{synonym}
</Text>
))}
</View>
</>
)}
</ArrowBox>
);
}}
></FlatList>;