effectScope 可以让不同的组件之间共享相同的依赖存活周期,即可以实现多个组件共享相同状态,并且实现所有的组件都被销毁后触发响应式状态销毁,这样优化了相同的内容重复注册,还共享了数据状态
import {ref, onScopeDispose, effectScope} from 'vue';
export function createSharedComposable(composable) {
let subscribers = 0
let state, scope
const dispose = () => {
if (scope && --subscribers <= 0) {
scope.stop()
state = scope = null
}
}
return (...args) => {
subscribers++
if (!state) {
scope = effectScope(true)
state = scope.run(() => composable(...args))
}
onScopeDispose(dispose)
return state
}
}
export let useShareMouse = createSharedComposable(useMouse)
export function useMouse() {
const x = ref(0)
const y = ref(0)
function handler(e) {
x.value = e.x
y.value = e.y
}
window.addEventListener('mousemove', handler)
onScopeDispose(() => {
console.log('onUnmounted')
window.removeEventListener('mousemove', handler)
})
return {x, y}
}