class Emitter {
|
constructor() {
|
this.listeners = new Map()
|
}
|
|
addListener(label, callback, vm) {
|
if (typeof callback === 'function') {
|
// eslint-disable-next-line no-unused-expressions
|
this.listeners.has(label) || this.listeners.set(label, [])
|
this.listeners.get(label).push({ callback, vm })
|
return true
|
}
|
return false
|
}
|
|
removeListener(label, callback, vm) {
|
const listeners = this.listeners.get(label)
|
let index
|
|
if (listeners?.length) {
|
index = listeners.reduce((i, listener, index) => {
|
if (typeof listener.callback === 'function' && listener.callback === callback && listener.vm === vm) {
|
// eslint-disable-next-line no-param-reassign
|
i = index
|
}
|
return i
|
}, -1)
|
|
if (index > -1) {
|
listeners.splice(index, 1)
|
this.listeners.set(label, listeners)
|
return true
|
}
|
}
|
return false
|
}
|
|
emit(label, ...args) {
|
const listeners = this.listeners.get(label)
|
|
if (listeners?.length) {
|
listeners.forEach(listener => {
|
listener.callback.call(listener.vm, ...args)
|
})
|
return true
|
}
|
return false
|
}
|
}
|
|
export default new Emitter()
|
