React Hooks & react forwardref hooks & useReducer

react how to call child component method in another child component

  1. left index list => right map
  2. right map back to default value, right child call left child methods ???

https://stackoverflow.com/a/37950970/5934465

https://reactjs.org/docs/hooks-reference.html#usereducer

https://reactjs.org/docs/forwarding-refs.html


store wrapper bug

OK

import React, {
Component,
// useState,
// useEffect,
} from 'react'; class ChildA extends Component {
constructor(props){
super(props);
this.state = {};
}
// clickRefTest = (key = ``) => {
// console.log(`ref click key`, key);
// };
clickCheck = (key) => {
console.log(`ref click key`, key);
};
render() {
return (
<div>
ChildA Components without @connect store
</div>
);
}
} // const ChildA = (props) => {
// return (
// <>
// <div>
// <button onClick={this.props.refClick}>Click</button>
// </div>
// </>
// );
// }; export {
ChildA,
}; export default ChildA;

bug

import React, {
Component,
// useState,
// useEffect,
} from 'react'; import { bindActionCreators } from 'redux';
import { connect } from 'dva'; import dashboardRegionActions from '../actions/dashboard.region.action'; import { SelectOption } from "./SelectOption";
import { SearchInput } from "./SearchInput"; import * as Provinces from "../Region/provinces.json"; import './index.less'; import {
Row,
Col,
} from "antd"; const mapStateToProps = ({ dashboard }) => ({
regionData: dashboard.regionData,
}); const mapDispatchToProps = dispatch => ({
actions: bindActionCreators(dashboardRegionActions, dispatch),
}); @connect(mapStateToProps, mapDispatchToProps,)
class SelectableIndexList extends Component {
constructor(props) {
super(props);
this.state = {
placeholder: "请输入省份名或其拼音",
provincesList: this.selectedFilter(Provinces.default),
initProvincesList: this.selectedFilter(Provinces.default),
};
}
selectedFilter = (provinces = []) => {
return provinces.map(obj => {
obj.selected = obj.key === "all";
return obj;
});
};
formatAdcode = (code = "all") => {
let adcode = 100000;
if (code !== "all") {
adcode = Number(`${code}0000`);
}
return adcode;
};
provincesFilter = (provincesList, key) => {
const result = provincesList.map(({name, key: code,}) => {
return {
name,
key: code,
selected: code === key,
};
}) || [];
return result;
};
clickRefTest = (key = ``) => {
console.log(`ref click key`, key);
};
clickCheck = (key) => {
const {
actions: {
changeRegion,
},
customizeRefCallback,
} = this.props;
const {
provincesList,
initProvincesList,
} = this.state;
const newProvincesList = this.provincesFilter(provincesList, key);
const newInitProvincesList = this.provincesFilter(initProvincesList, key);
this.setState({
provincesList: newProvincesList,
initProvincesList: newInitProvincesList,
}, () => {
changeRegion(`${key}`);
customizeRefCallback();
});
};
handleCheckableTagChange = (value) => {
const {
initProvincesList: provincesList,
} = this.state;
const newProvincesList = provincesList.filter(obj => obj.name.includes(value)) || [];
this.setState({
provincesList: newProvincesList,
});
};
inputChangeHandle = (e) => {
const value = e.target.value;
this.handleCheckableTagChange(value);
};
render() {
const {
placeholder,
provincesList,
} = this.state;
return (
<>
<Row className="selectable-index-list">
<Col span={24} className="input-box">
{
SearchInput({
placeholder: placeholder,
inputChangeHandle: this.inputChangeHandle,
})
}
</Col>
<Col span={24} className="option-box">
<SelectOption
provincesList={provincesList}
clickCheck={this.clickCheck}
/>
</Col>
</Row>
</>
);
}
} export {
SelectableIndexList,
}; export default SelectableIndexList;

solution

@connect & withRef

missing null

OK

width !== with

withRef


import React, {
Component,
// useState,
// useEffect,
} from 'react'; import { bindActionCreators } from 'redux';
import { connect } from 'dva'; import dashboardRegionActions from '../actions/dashboard.region.action'; import { SelectOption } from "./SelectOption";
import { SearchInput } from "./SearchInput"; import * as Provinces from "../Region/provinces.json"; import './index.less'; import {
Row,
Col,
} from "antd"; const mapStateToProps = ({ dashboard }) => ({
regionData: dashboard.regionData,
}); const mapDispatchToProps = dispatch => ({
actions: bindActionCreators(dashboardRegionActions, dispatch),
}); // 第四个参数 ??? withRef
@connect(mapStateToProps, mapDispatchToProps, null, { withRef: true,})
class SelectableIndexList extends Component {
constructor(props) {
super(props);
this.state = {
placeholder: "请输入省份名或其拼音",
provincesList: this.selectedFilter(Provinces.default),
initProvincesList: this.selectedFilter(Provinces.default),
};
}
selectedFilter = (provinces = []) => {
return provinces.map(obj => {
obj.selected = obj.key === "all";
return obj;
});
};
formatAdcode = (code = "all") => {
let adcode = 100000;
if (code !== "all") {
adcode = Number(`${code}0000`);
}
return adcode;
};
provincesFilter = (provincesList, key) => {
const result = provincesList.map(({name, key: code,}) => {
return {
name,
key: code,
selected: code === key,
};
}) || [];
return result;
};
clickRefTest = (key = ``) => {
console.log(`ref click key`, key);
};
clickCheck = (key) => {
const {
actions: {
changeRegion,
},
customizeRefCallback,
} = this.props;
const {
provincesList,
initProvincesList,
} = this.state;
const newProvincesList = this.provincesFilter(provincesList, key);
const newInitProvincesList = this.provincesFilter(initProvincesList, key);
this.setState({
provincesList: newProvincesList,
initProvincesList: newInitProvincesList,
}, () => {
changeRegion(`${key}`);
customizeRefCallback();
});
};
handleCheckableTagChange = (value) => {
const {
initProvincesList: provincesList,
} = this.state;
const newProvincesList = provincesList.filter(obj => obj.name.includes(value)) || [];
this.setState({
provincesList: newProvincesList,
});
};
inputChangeHandle = (e) => {
const value = e.target.value;
this.handleCheckableTagChange(value);
};
render() {
const {
placeholder,
provincesList,
} = this.state;
return (
<>
<Row className="selectable-index-list">
<Col span={24} className="input-box">
{
SearchInput({
placeholder: placeholder,
inputChangeHandle: this.inputChangeHandle,
})
}
</Col>
<Col span={24} className="option-box">
<SelectOption
provincesList={provincesList}
clickCheck={this.clickCheck}
/>
</Col>
</Row>
</>
);
}
} export {
SelectableIndexList,
}; export default SelectableIndexList;

withRef

https://github.com/reduxjs/react-redux/issues/1053

forwardRef

https://stackoverflow.com/questions/53819335/withref-is-removed-to-access-the-wrapped-instance-use-a-ref-on-the-connected-c

https://medium.com/@mehran.khan/using-refs-with-react-redux-6-how-to-use-refs-on-connected-components-4b80d4ea7300



xgqfrms 2012-2020

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