-import { Directive, EventEmitter, Input, OnInit, Output } from '@angular/core'
+import { Directive, EventEmitter, Input, OnDestroy, OnInit, Output } from '@angular/core'
import 'rxjs/add/operator/debounceTime'
import 'rxjs/add/operator/distinct'
import 'rxjs/add/operator/distinctUntilChanged'
import 'rxjs/add/operator/filter'
import 'rxjs/add/operator/map'
+import 'rxjs/add/operator/share'
import 'rxjs/add/operator/startWith'
import 'rxjs/add/operator/throttleTime'
import { fromEvent } from 'rxjs/observable/fromEvent'
-import 'rxjs/add/operator/share'
+import { Subscription } from 'rxjs/Subscription'
@Directive({
selector: '[myInfiniteScroller]'
})
-export class InfiniteScrollerDirective implements OnInit {
+export class InfiniteScrollerDirective implements OnInit, OnDestroy {
private static PAGE_VIEW_TOP_MARGIN = 500
@Input() containerHeight: number
private decimalLimit = 0
private lastCurrentBottom = -1
private lastCurrentTop = 0
+ private scrollDownSub: Subscription
+ private scrollUpSub: Subscription
+ private pageChangeSub: Subscription
constructor () {
this.decimalLimit = this.percentLimit / 100
if (this.autoLoading === true) return this.initialize()
}
+ ngOnDestroy () {
+ if (this.scrollDownSub) this.scrollDownSub.unsubscribe()
+ if (this.scrollUpSub) this.scrollUpSub.unsubscribe()
+ if (this.pageChangeSub) this.pageChangeSub.unsubscribe()
+ }
+
initialize () {
// Emit the last value
- const throttleOptions = { leading: false, trailing: true }
+ const throttleOptions = { leading: true, trailing: true }
const scrollObservable = fromEvent(window, 'scroll')
.startWith(true)
.throttleTime(200, undefined, throttleOptions)
.map(() => ({ current: window.scrollY, maximumScroll: document.body.clientHeight - window.innerHeight }))
+ .distinctUntilChanged((o1, o2) => o1.current === o2.current)
.share()
// Scroll Down
- scrollObservable
+ this.scrollDownSub = scrollObservable
// Check we scroll down
.filter(({ current }) => {
const res = this.lastCurrentBottom < current
.subscribe(() => this.nearOfBottom.emit())
// Scroll up
- scrollObservable
+ this.scrollUpSub = scrollObservable
// Check we scroll up
.filter(({ current }) => {
const res = this.lastCurrentTop > current
.subscribe(() => this.nearOfTop.emit())
// Page change
- scrollObservable
+ this.pageChangeSub = scrollObservable
.distinct()
.map(({ current }) => this.calculateCurrentPage(current))
.distinctUntilChanged()