$ npm install mini-store
A state store for React component.
When you want to share a component's state to another one, a commom pattern in React world is lifting state up. But one problem of this pattern is performance, assume we have a component in following hierarchy:
<Parent>
<ChildA />
<ChildB />
<ChildC />
</Parent>
ChildA
want to share state with ChildB
, so you lifting ChildA
's state up to Parent
. Now, when ChildA
's state changes, the whole Parent
will rerender, includes ChildC
which should not happen.
Redux do a good job at this situation throgh keeping all state in store, then component can subscribe state's changes, and only connected components will rerender. But redux
+ react-redux
is overkill when you are writing a component library. So I wrote this little library, It's like Redux's store without "reducer" and "dispatch".
import { Provider, create, connect } from 'mini-store';
class Counter extends React.Component {
constructor(props) {
super(props);
this.store = create({
count: 0,
});
}
render() {
return (
<Provider store={this.store}>
<div>
<Buttons />
<Result />
</div>
</Provider>
)
}
}
@connect()
class Buttons extends React.Component {
handleClick = (step) => () => {
const { store } = this.props;
const { count } = store.getState();
store.setState({ count: count + step });
}
render() {
return (
<div>
<button onClick={this.handleClick(1)}>+</button>
<button onClick={this.handleClick(-1)}>-</button>
</div>
);
}
}
@connect((state) => ({ count: state.count }))
class Result extends React.Component {
render() {
return (
<div>{this.props.count}</div>
);
};
}
create(initialState)
Creates a store that holds the state. initialState
is plain object.
<Provider store>
Makes the store available to the connect() calls in the component hierarchy below.
connect(mapStateToProps)
Connects a React component to the store. It works like Redux's connect
, but only accept mapStateToProps
. The connected component also receive store
as a prop, you can call setState
directly on store.
MIT
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