counter.state.ts

import { State, StateContext } from '@ngxs/store';
import { Receiver } from '@ngxs-labs/emitter';

export interface CounterStateModel {
    value: number;
}

@State<CounterStateModel>({
    name: 'counter',
    defaults: {
        value: 0
    }
})
export class CounterState {
    @Receiver()
    public static increment({ setState, getState }: StateContext<CounterStateModel>): void {
        setState({
            value: getState().value + 1
        });
    }

    @Receiver({ type: '[Counter] Decrement' })
    public static decrement({ setState, getState }: StateContext<CounterStateModel>): void {
        setState({
            value: getState().value - 1
        });
    }
}