将组件状态传递给 react-apollo 的 compose 中的查询变量
Passing components state to query variables inside react-apollo's compose
以下 React 组件工作正常,我能够使用 Apollo-React 查询 GraphQL 端点。在这种特定情况下,我使用 Apollo-React 的 compose
函数在同一组件中添加多个查询。
我想在 HOC variables
字段中动态注入 userId。
有办法吗?因为简单地调用函数 getUser()
似乎不起作用,所以我只得到一个承诺。
class AllCardsScreen extends Component {
state = {
query: '',
userCardsById: [],
userId:'',
loading: false,
};
getUser = async () => {
await Auth.currentUserInfo()
.then((data) => {
this.setState({ userId: data.attributes.sub});
})
.catch(error => console.log(`Error: ${error.message}`));
};
render() {
return (
<View style={styles.container}>
<FlatList
data={this.props.userCardsList}
keyExtractor={this.keyExtractor}
renderItem={this.renderItem}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
keyboardShouldPersistTaps="handled"
/>
</View>
);
}
export default compose(
graphql(ListCards, {
options: (props) => ({
fetchPolicy: 'cache-and-network',
variables: { userId : '18e946df-d3de-49a8-98b3-8b6d74dfd652'}
}),
props: (props) => ({
userCardsList: props.data.userCardsList ? props.data.userCardsList.userCards : [],
}),
})
)(AllCardsScreen);
编辑:
这是最终的工作版本,也是基于丹尼尔的建议(Thx Daniel),在 HOC Apollo-graphQl 增强器中注入了一个 API 异步调用。我必须调用 data.props.refetch()
函数来更新 variables
值。
class AuthWrapper extends React.Component {
state = {
userId: null,
}
async componentDidMount () {
const data = await Auth.currentUserInfo()
this.setState({ userId: data.attributes.sub})
}
render () {
return this.state.userId
? <AllCardsScreen {...this.state} {...this.props}/>
: null
}
}
class AllCardsScreen extends Component {
state = {
query: '',
userCardsById: [],
userId:'',
loading: false,
};
componentDidMount() {
this.props.dataRefetch(this.props.userId)
SplashScreen.hide();
}
render() {
return (
<View style={styles.container}>
<FlatList
data={this.props.userCardsList}
keyExtractor={this.keyExtractor}
renderItem={this.renderItem}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
keyboardShouldPersistTaps="handled"
/>
</View>
);
}
export default compose(
graphql(ListCards, {
options: (props) => ({
fetchPolicy: 'cache-and-network',
variables: { userId : ''}
}),
props: (props) => ({
userCardsList: props.data.userCardsList ? props.data.userCardsList.userCards : [],
dataRefetch: (userId) => {
props.data.refetch({userId})
},
}),
})
)(AllCardsScreen);
graphql
HOC 仅使用 props——因为它实际上只是包装了它传递的组件,所以它无法访问该组件的状态。也没有办法在 HOC 配置中异步获取数据。
最简单的解决方案是将状态提升到现有父组件或包装现有组件的新组件中。例如:
class WrapperComponent extends Component {
state = {
userId: null,
}
async componentDidMount () {
const data = await Auth.currentUserInfo()
this.setState({ userId: data.attributes.sub})
}
render () {
// May want to render nothing or a loading indicator if userId is null
return <AllCardsScreen userId={this.state.userId} {...otherProps} />
}
}
或者,您可以创建自己的 HOC 来封装相同的逻辑:
function authHOC(WrappedComponent) {
return class AuthWrapper extends React.Component {
state = {
userId: null,
}
async componentDidMount () {
const data = await Auth.currentUserInfo()
this.setState({ userId: data.attributes.sub})
}
render () {
return this.state.userId
? <WrappedComponent {...this.props} userId={this.state.userId} />
: null
}
}
}
以下 React 组件工作正常,我能够使用 Apollo-React 查询 GraphQL 端点。在这种特定情况下,我使用 Apollo-React 的 compose
函数在同一组件中添加多个查询。
我想在 HOC variables
字段中动态注入 userId。
有办法吗?因为简单地调用函数 getUser()
似乎不起作用,所以我只得到一个承诺。
class AllCardsScreen extends Component {
state = {
query: '',
userCardsById: [],
userId:'',
loading: false,
};
getUser = async () => {
await Auth.currentUserInfo()
.then((data) => {
this.setState({ userId: data.attributes.sub});
})
.catch(error => console.log(`Error: ${error.message}`));
};
render() {
return (
<View style={styles.container}>
<FlatList
data={this.props.userCardsList}
keyExtractor={this.keyExtractor}
renderItem={this.renderItem}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
keyboardShouldPersistTaps="handled"
/>
</View>
);
}
export default compose(
graphql(ListCards, {
options: (props) => ({
fetchPolicy: 'cache-and-network',
variables: { userId : '18e946df-d3de-49a8-98b3-8b6d74dfd652'}
}),
props: (props) => ({
userCardsList: props.data.userCardsList ? props.data.userCardsList.userCards : [],
}),
})
)(AllCardsScreen);
编辑:
这是最终的工作版本,也是基于丹尼尔的建议(Thx Daniel),在 HOC Apollo-graphQl 增强器中注入了一个 API 异步调用。我必须调用 data.props.refetch()
函数来更新 variables
值。
class AuthWrapper extends React.Component {
state = {
userId: null,
}
async componentDidMount () {
const data = await Auth.currentUserInfo()
this.setState({ userId: data.attributes.sub})
}
render () {
return this.state.userId
? <AllCardsScreen {...this.state} {...this.props}/>
: null
}
}
class AllCardsScreen extends Component {
state = {
query: '',
userCardsById: [],
userId:'',
loading: false,
};
componentDidMount() {
this.props.dataRefetch(this.props.userId)
SplashScreen.hide();
}
render() {
return (
<View style={styles.container}>
<FlatList
data={this.props.userCardsList}
keyExtractor={this.keyExtractor}
renderItem={this.renderItem}
ItemSeparatorComponent={this.renderSeparator}
ListHeaderComponent={this.renderHeader}
keyboardShouldPersistTaps="handled"
/>
</View>
);
}
export default compose(
graphql(ListCards, {
options: (props) => ({
fetchPolicy: 'cache-and-network',
variables: { userId : ''}
}),
props: (props) => ({
userCardsList: props.data.userCardsList ? props.data.userCardsList.userCards : [],
dataRefetch: (userId) => {
props.data.refetch({userId})
},
}),
})
)(AllCardsScreen);
graphql
HOC 仅使用 props——因为它实际上只是包装了它传递的组件,所以它无法访问该组件的状态。也没有办法在 HOC 配置中异步获取数据。
最简单的解决方案是将状态提升到现有父组件或包装现有组件的新组件中。例如:
class WrapperComponent extends Component {
state = {
userId: null,
}
async componentDidMount () {
const data = await Auth.currentUserInfo()
this.setState({ userId: data.attributes.sub})
}
render () {
// May want to render nothing or a loading indicator if userId is null
return <AllCardsScreen userId={this.state.userId} {...otherProps} />
}
}
或者,您可以创建自己的 HOC 来封装相同的逻辑:
function authHOC(WrappedComponent) {
return class AuthWrapper extends React.Component {
state = {
userId: null,
}
async componentDidMount () {
const data = await Auth.currentUserInfo()
this.setState({ userId: data.attributes.sub})
}
render () {
return this.state.userId
? <WrappedComponent {...this.props} userId={this.state.userId} />
: null
}
}
}