primeng/fesm2015/primeng-scrolltop.js

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import { Component, ChangeDetectionStrategy, ViewEncapsulation, ElementRef, ChangeDetectorRef, Input, NgModule } from '@angular/core';
import { CommonModule } from '@angular/common';
import { trigger, state, style, transition, animate } from '@angular/animations';
import { DomHandler } from 'primeng/dom';

class ScrollTop {
    constructor(el, cd) {
        this.el = el;
        this.cd = cd;
        this.target = "window";
        this.threshold = 400;
        this.icon = "pi pi-chevron-up";
        this.behavior = "smooth";
        this.showTransitionOptions = '.15s';
        this.hideTransitionOptions = '.15s';
        this.visible = false;
    }
    ngOnInit() {
        if (this.target === 'window')
            this.bindDocumentScrollListener();
        else if (this.target === 'parent')
            this.bindParentScrollListener();
    }
    onClick() {
        let scrollElement = this.target === 'window' ? window : this.el.nativeElement.parentElement;
        scrollElement.scroll({
            top: 0,
            behavior: this.behavior
        });
    }
    onEnter() {
        this.el.nativeElement.children[0].style.zIndex = DomHandler.generateZIndex();
    }
    checkVisibility(scrollY) {
        if (scrollY > this.threshold)
            this.visible = true;
        else
            this.visible = false;
        this.cd.markForCheck();
    }
    bindParentScrollListener() {
        this.scrollListener = () => {
            this.checkVisibility(this.el.nativeElement.parentElement.scrollTop);
        };
        this.el.nativeElement.parentElement.addEventListener('scroll', this.scrollListener);
    }
    bindDocumentScrollListener() {
        this.scrollListener = () => {
            this.checkVisibility(DomHandler.getWindowScrollTop());
        };
        window.addEventListener('scroll', this.scrollListener);
    }
    unbindParentScrollListener() {
        if (this.scrollListener) {
            this.el.nativeElement.parentElement.removeEventListener('scroll', this.scrollListener);
            this.scrollListener = null;
        }
    }
    unbindDocumentScrollListener() {
        if (this.scrollListener) {
            window.removeEventListener('scroll', this.scrollListener);
            this.scrollListener = null;
        }
    }
    containerClass() {
        return {
            'p-scrolltop p-link p-component': true,
            'p-scrolltop-sticky': this.target !== 'window'
        };
    }
    ngOnDestroy() {
        if (this.target === 'window')
            this.unbindDocumentScrollListener();
        else if (this.target === 'parent')
            this.unbindParentScrollListener();
    }
}
ScrollTop.decorators = [
    { type: Component, args: [{
                selector: 'p-scrollTop',
                template: `
        <button  *ngIf="visible" [@animation]="{value: 'open', params: {showTransitionParams: showTransitionOptions, hideTransitionParams: hideTransitionOptions}}" (@animation.start)="onEnter()"
            [ngClass]="containerClass()" (click)="onClick()" [class]="styleClass" [ngStyle]="style" type="button">
            <span [class]="icon" [ngClass]="'p-scrolltop-icon'"></span>
        </button>
    `,
                changeDetection: ChangeDetectionStrategy.OnPush,
                encapsulation: ViewEncapsulation.None,
                animations: [
                    trigger('animation', [
                        state('void', style({
                            opacity: 0
                        })),
                        state('open', style({
                            opacity: 1
                        })),
                        transition('void => open', animate('{{showTransitionParams}}')),
                        transition('open => void', animate('{{hideTransitionParams}}')),
                    ])
                ],
                styles: [".p-scrolltop{align-items:center;bottom:20px;display:flex;justify-content:center;position:fixed;right:20px}.p-scrolltop-sticky{position:sticky}.p-scrolltop-sticky.p-link{margin-left:auto}"]
            },] }
];
ScrollTop.ctorParameters = () => [
    { type: ElementRef },
    { type: ChangeDetectorRef }
];
ScrollTop.propDecorators = {
    styleClass: [{ type: Input }],
    style: [{ type: Input }],
    target: [{ type: Input }],
    threshold: [{ type: Input }],
    icon: [{ type: Input }],
    behavior: [{ type: Input }],
    showTransitionOptions: [{ type: Input }],
    hideTransitionOptions: [{ type: Input }]
};
class ScrollTopModule {
}
ScrollTopModule.decorators = [
    { type: NgModule, args: [{
                imports: [CommonModule],
                exports: [ScrollTop],
                declarations: [ScrollTop]
            },] }
];

/**
 * Generated bundle index. Do not edit.
 */

export { ScrollTop, ScrollTopModule };
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