@xstate/vue
The @xstate/vue package contains utilities for using XState with Vue.
Templatesβ
Use the following templates to get started quickly with XState and Vue:
Installationβ
Install the latest versions of both xstate and @xstate/vue. xstate is a peer dependency of @xstate/vue.
- npm
- pnpm
- yarn
npm install xstate @xstate/vue
pnpm install xstate @xstate/vue
yarn add xstate @xstate/vue
APIβ
useActor(actorLogic, options?)β
A Vue composition function that creates an actor from the given actorLogic and starts an actor ref that runs for the lifetime of the component.
Argumentsβ
actorLogic- An XState machineoptions(optional) - Actor options
Returns { snapshot, send, actorRef }:
snapshot- Represents the current snapshot (state) of the machine as an XStateStateobject.send- A function that sends events to the running actor.actorRef- The created actor ref.
useMachine(machine, options?)β
A Vue composition function that creates an actor from the given machine and starts an actor that runs for the lifetime of the component.
Argumentsβ
machine- An XState machineoptions(optional) - Actor options
Returns { snapshot, send, actorRef }:
snapshot- Represents the current snapshot (state) of the machine as an XStateStateobject.send- A function that sends events to the running actor.actorRef- The created actor ref.
useActorRef(actorLogic, options?, observer?)β
A Vue composition function that returns the actorRef created from the actorLogic with the actor options, if specified. It also sets up a subscription to the actorRef with the observer, if provided.
Argumentsβ
actorLogic- Actor logicoptions(optional) - Actor optionsobserver(optional) - an observer or listener that listens to snapshot updates:- an observer (e.g.,
{ next: (snapshot) => {/* ... */} }) - or a listener (e.g.,
(snapshot) => {/* ... */})
- an observer (e.g.,
Examplesβ
import { useActorRef } from '@xstate/vue';
import { someMachine } from '../path/to/someMachine';
export default {
setup() {
const actorRef = useActorRef(someMachine);
return actorRef;
},
};
With options + listener:
import { useInterpret } from '@xstate/vue';
import { someMachine } from '../path/to/someMachine';
export default {
setup() {
const actor = useInterpret(
someMachine,
{
actions: {
/* ... */
},
},
(state) => {
// subscribes to state changes
console.log(state.value);
},
);
// ...
},
};
useSelector(actor, selector, compare?, getSnapshot?)β
A Vue composition function that returns the selected value from the snapshot of an actorRef, such as an actor. This hook will only cause a rerender if the selected value changes, as determined by the optional compare function.
Argumentsβ
actorRef- an actor or an actor-like object that contains.send(...)and.subscribe(...)methods.selector- a function that takes in an actorβs "current state" (snapshot) as an argument and returns the desired selected value.compare(optional) - a function that determines if the current selected value is the same as the previous selected value.getSnapshot(optional) - a function that should return the latest emitted value from theactorRef.- Defaults to attempting to get the
actor.state, or returningundefinedif that does not exist. Will automatically pull the state from actors.
- Defaults to attempting to get the
import { useSelector } from '@xstate/vue';
const selectCount = (snapshot) => snapshot.context.count;
export default {
props: ['actor'],
setup(props) {
const count = useSelector(props.actor, selectCount);
// ...
return { count };
},
};
With compare function:
import { useSelector } from '@xstate/vue';
const selectUser = (state) => state.context.user;
const compareUser = (prevUser, nextUser) => prevUser.id === nextUser.id;
export default {
props: ['actor'],
setup(props) {
const user = useSelector(props.actor, selectUser, compareUser);
// ...
return { user };
},
};
With useActorRef(...):
import { useActorRef, useSelector } from '@xstate/vue';
import { someMachine } from '../path/to/someMachine';
const selectCount = (snapshot) => snapshot.context.count;
export default {
setup() {
const actorRef = useActorRef(someMachine);
const count = useSelector(actorRef, selectCount);
// ...
return { count, actorRef };
},
};