reactjs - react redux typescript : connect has missing type error

Question

我正在尝试让 react-redux 应用程序与 typescript 一起使用，但我一直在绕着同样的错误转圈。以下代码编译并产生预期结果

// State definition
interface HelloWorldState {
    clickCount: number
}
interface AppState extends HelloWorldState {}


// Props definitions
interface HelloWorldProps {
    count: number
}


// Actions
const CLICK = 'CLICK';
const click = () => {return {type:CLICK}};


// Reducers
function clickCount(state:number = 0, action:Action) {
    if (typeof state === 'undefined') {
        return 0;
    }
    switch (action.type) {
        case CLICK:
            return state + 1;
        default:
            return state;
    }
}
let rootReducer = combineReducers({
    clickCount
});


// Store
let store = createStore(rootReducer);


// Components
class HelloWorld extends React.Component<any, any> {
    render() {
        return <div onClick={this.handleClick.bind(this)}>Hello world "{this.props.count}"</div>
    }

    handleClick() {
        store.dispatch(click())
    }
}


// Container components
const mapStateToProps = (state:AppState):HelloWorldState => {
    return Immutable.fromJS({
        count: state.clickCount
    })
};
const ConnectedHelloWorld = connect(
    mapStateToProps
)(HelloWorld);

render(
    <Provider store={store}>
        <ConnectedHelloWorld/>
    </Provider>,
    container
);

太棒了!但我使用的是 TypeScript，因为我想在编译时进行类型检查。类型检查最重要的是状态和 Prop 。所以而不是 class HelloWorld extends React.Component<any, any> , 我想做 class HelloWorld extends React.Component<HelloWorldProps, any> .然而，当我这样做时，我从对 render 的调用中得到以下编译错误

TS2324:Property 'count' is missing in type 'IntrinsicAttributes & IntrinsicClassAttributes<HelloWorld> & HelloWorldProps & { children?: React...'.

我真的不明白为什么。 count IS 出现在 HelloWordProps 中定义，它是由 reducer 提供的，所以我应该没问题，对吧？类似的问题表明这是一个推理问题，我应该声明对 connect 的调用类型。 , 但我似乎无法找出方法

包.json

{
  "name": "reacttsx",
  "scripts": {
    "build": "webpack"
  },
  "devDependencies": {
    "ts-loader": "^1.3.3",
    "typescript": "^2.1.5",
    "webpack": "^1.14.0",
    "typings": "^2.1.0"
  },
  "dependencies": {
    "es6-promise": "^4.0.5",
    "flux": "^3.1.2",
    "immutable": "^3.8.1",
    "isomorphic-fetch": "^2.2.1",
    "jquery": "^3.1.1",
    "react": "^15.4.2",
    "react-dom": "^15.4.2",
    "react-redux": "^5.0.2",
    "redux": "^3.6.0",
    "redux-logger": "^2.7.4",
    "redux-thunk": "^2.2.0"
  }
}

打字.json

{
  "dependencies": {
    "flux": "registry:npm/flux#2.1.1+20160601175240",
    "immutable": "registry:npm/immutable#3.7.6+20160411060006",
    "react": "registry:npm/react#15.0.1+20170104200836",
    "react-dom": "registry:npm/react-dom#15.0.1+20160826174104",
    "react-redux": "registry:npm/react-redux#4.4.0+20160614222153",
    "redux-logger": "registry:dt/redux-logger#2.6.0+20160726205300",
    "redux-thunk": "registry:npm/redux-thunk#2.0.0+20160525185520"
  },
  "globalDependencies": {
    "es6-promise": "registry:dt/es6-promise#0.0.0+20160726191732",
    "isomorphic-fetch": "registry:dt/isomorphic-fetch#0.0.0+20170120045107",
    "jquery": "registry:dt/jquery#1.10.0+20170104155652",
    "redux": "registry:dt/redux#3.5.2+20160703092728",
    "redux-thunk": "registry:dt/redux-thunk#2.1.0+20160703120921"
  }
}

更新

因为它提示count丢失了，我尝试更新到

render(
    <Provider store={store}>
        <ConnectedHelloWorld count={0}/>
    </Provider>,
    container
);

这解决了这个问题。所以问题是编译器不知道 Provider正在提供计数。提供商使用商店。商店应该有 clickCount映射到 count 的值由容器组件。

我注意到我忘记了商店的初始状态。因此，即使类型已 check out ，状态也将为空。我将其更新为

// Store
let initialState:AppState = {clickCount: 0};
let store = createStore(rootReducer, initialState);

现在我确定 clickCount在商店中设置正确。所以我希望 mapStateToProps函数取 AppState并返回 HelloWorldProps按照指定，然后是 Provider应该提供计数值。这是真的，但编译器看不到它。

那么如何补救呢？

Answer 1

在我的例子中，我在 connect 函数中为 mapDispatchToProps 参数传递了 null，因为我没有为此组件使用分派(dispatch):

export default connect(mapStateToProps, null)(MainLayout);

将其更改为仅省略 mapDispatchToProps 参数为我修复了它

export default connect(mapStateToProps)(MainLayout);