135 lines
4.5 KiB
TypeScript
135 lines
4.5 KiB
TypeScript
// (C) Copyright 2015 Martin Dougiamas
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
import { Component, Input, Output, EventEmitter, OnChanges, SimpleChange, Optional, ViewChild, ElementRef } from '@angular/core';
|
|
import { InfiniteScroll, Content } from 'ionic-angular';
|
|
import { CoreDomUtilsProvider } from '@providers/utils/dom';
|
|
|
|
/**
|
|
* Component to show a infinite loading trigger and spinner while more data is being loaded.
|
|
*
|
|
* Usage:
|
|
* <core-infinite-loading [action]="loadingAction" [enabled]="dataLoaded"></core-inifinite-loading>
|
|
*/
|
|
@Component({
|
|
selector: 'core-infinite-loading',
|
|
templateUrl: 'core-infinite-loading.html',
|
|
})
|
|
export class CoreInfiniteLoadingComponent implements OnChanges {
|
|
@Input() enabled: boolean;
|
|
@Input() error = false;
|
|
@Input() position = 'bottom';
|
|
@Output() action: EventEmitter<() => void>; // Will emit an event when triggered.
|
|
|
|
@ViewChild('topbutton') topButton: ElementRef;
|
|
@ViewChild('infinitescroll') infiniteEl: ElementRef;
|
|
@ViewChild('bottombutton') bottomButton: ElementRef;
|
|
@ViewChild('spinnercontainer') spinnerContainer: ElementRef;
|
|
|
|
loadingMore = false; // Hide button and avoid loading more.
|
|
|
|
protected infiniteScroll: InfiniteScroll;
|
|
|
|
constructor(@Optional() private content: Content, private domUtils: CoreDomUtilsProvider) {
|
|
this.action = new EventEmitter();
|
|
}
|
|
|
|
/**
|
|
* Detect changes on input properties.
|
|
*
|
|
* @param changes Changes.
|
|
*/
|
|
ngOnChanges(changes: {[name: string]: SimpleChange}): void {
|
|
if (changes.enabled && this.enabled && this.position == 'bottom') {
|
|
// Infinite scroll enabled. If the list doesn't fill the full height, infinite scroll isn't triggered automatically.
|
|
// Send a fake scroll event to make infinite scroll check if it should load more items.
|
|
setTimeout(() => {
|
|
const event: any = new Event('scroll');
|
|
this.content.ionScroll.emit(event);
|
|
}, 400);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Load More items calling the action provided.
|
|
*
|
|
* @param infiniteScroll Infinite scroll object only if triggered from the scroll.
|
|
*/
|
|
loadMore(infiniteScroll?: InfiniteScroll): void {
|
|
if (this.loadingMore) {
|
|
return;
|
|
}
|
|
|
|
if (infiniteScroll) {
|
|
this.infiniteScroll = infiniteScroll;
|
|
}
|
|
this.loadingMore = true;
|
|
|
|
this.action.emit(this.complete.bind(this));
|
|
}
|
|
|
|
/**
|
|
* Complete loading.
|
|
*/
|
|
complete(): void {
|
|
if (this.position == 'top') {
|
|
// Wait a bit before allowing loading more, otherwise it could be re-triggered automatically when it shouldn't.
|
|
setTimeout(this.completeLoadMore.bind(this), 400);
|
|
} else {
|
|
this.completeLoadMore();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Complete loading.
|
|
*/
|
|
protected completeLoadMore(): void {
|
|
this.loadingMore = false;
|
|
this.infiniteScroll && this.infiniteScroll.complete();
|
|
this.infiniteScroll = undefined;
|
|
|
|
// More items loaded. If the list doesn't fill the full height, infinite scroll isn't triggered automatically.
|
|
// Send a fake scroll event to make infinite scroll check if it should load more items.
|
|
setTimeout(() => {
|
|
const event: any = new Event('scroll');
|
|
this.content.ionScroll.emit(event);
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Get the height of the element.
|
|
*
|
|
* @return Height.
|
|
*/
|
|
getHeight(): number {
|
|
return this.getElementHeight(this.topButton) + this.getElementHeight(this.infiniteEl) +
|
|
this.getElementHeight(this.bottomButton) + this.getElementHeight(this.spinnerContainer);
|
|
}
|
|
|
|
/**
|
|
* Get the height of an element.
|
|
*
|
|
* @param element Element ref.
|
|
* @return Height.
|
|
*/
|
|
protected getElementHeight(element: ElementRef): number {
|
|
if (element && element.nativeElement) {
|
|
return this.domUtils.getElementHeight(element.nativeElement, true, true, true);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
}
|