Redux合并来自不同reducer的2个状态

Question

I have 2 reducers (categoryReducer and productReducer) which fetch data from an API. Both set a loading and error state. I combine these 2 reducers with combineReducers:

const rootReducer = combineReducers({
 categoryReducer,
 productReducer
});

Is it possible to merge the loading and error state of these 2 reducers ? Because my Application should display a loading text, whenever the loading state is true. So that I can do something like:

if (this.props.isLoading)
   ...

instead of two different loading States

if (this.props.isCategoryLoading || this.props.isProductLoading)
   ...

Answer 1

You can use selector and caculate isLoading from isCategoryLoading and isProductLoading within the selector:

// Your container component:
const mapStateToProps = (state) => ({
    isLoading: getIsLoading(state)
});

export const YourContainer = connect(
    mapStateToProps,
    mapDispatchToProps
)(YourComponent);

// Your selector:

export const getIsLoading = state => state.isCategoryLoading || state.isProductLoading;