Created
September 22, 2017 12:29
-
-
Save gmorel/c3d1edd7cf91dfbe379ed09ae81c7cbe to your computer and use it in GitHub Desktop.
Allow to scroll horizontally
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
import {ElementRef, Injectable} from "@angular/core"; | |
@Injectable() | |
export class DataTableHorizontalScroller { | |
private static readonly DATATABLE_BODY_CSS_SELECTOR = '.datatable-body'; | |
private static readonly SCROLL_DISTANCE_IN_PX = 100; | |
private lastScrollLeft: number; | |
public constructor( | |
private elementRef: ElementRef, | |
) {} | |
/** | |
* @returns {boolean} False if no more horizontal scroll possible | |
*/ | |
public scrollLeft(): boolean { | |
let dataTableBodyDom = this.elementRef.nativeElement.querySelector(DataTableHorizontalScroller.DATATABLE_BODY_CSS_SELECTOR); | |
if (this.isMaxScrollLeftReached()) { | |
return false; | |
} | |
let previous: number = DataTableHorizontalScroller.SCROLL_DISTANCE_IN_PX; | |
this.lastScrollLeft = dataTableBodyDom.scrollLeft; | |
dataTableBodyDom.scrollLeft -= previous; | |
return true; | |
} | |
/** | |
* @returns {boolean} False if no more horizontal scroll possible | |
*/ | |
public scrollRight(): boolean { | |
let dataTableBodyDom = this.elementRef.nativeElement.querySelector(DataTableHorizontalScroller.DATATABLE_BODY_CSS_SELECTOR); | |
if (this.isMaxScrollRightReached()) { | |
return false; | |
} | |
let next: number = DataTableHorizontalScroller.SCROLL_DISTANCE_IN_PX; | |
this.lastScrollLeft = dataTableBodyDom.scrollLeft; | |
dataTableBodyDom.scrollLeft += next; | |
return true; | |
} | |
private isMaxScrollLeftReached(): boolean { | |
let next: number = this.createNextScrollDistance(); | |
return next <= DataTableHorizontalScroller.SCROLL_DISTANCE_IN_PX; | |
} | |
private isMaxScrollRightReached(): boolean { | |
let dataTableBodyDom = this.elementRef.nativeElement.querySelector(DataTableHorizontalScroller.DATATABLE_BODY_CSS_SELECTOR); | |
let maxScroll: number = dataTableBodyDom.scrollWidth - dataTableBodyDom.clientWidth; | |
let next: number = this.createNextScrollDistance(); | |
return next > maxScroll; | |
} | |
private createNextScrollDistance(): number { | |
let dataTableBodyDom = this.elementRef.nativeElement.querySelector(DataTableHorizontalScroller.DATATABLE_BODY_CSS_SELECTOR); | |
return dataTableBodyDom.scrollLeft + DataTableHorizontalScroller.SCROLL_DISTANCE_IN_PX; | |
} | |
} |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment