Last active
June 11, 2020 14:59
-
-
Save mopcweb/f48c6931a359eb6a521ef6bbad4c90dd to your computer and use it in GitHub Desktop.
Angular 2+ directive for clsx package
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
| // Usage | |
| // <div [clsx]="[true && 'Test', classes.Test]"></div> | |
| import { Directive, Input, ElementRef, OnChanges } from '@angular/core'; | |
| import clsx, { ClassValue } from 'clsx'; | |
| /** | |
| * Directive for module clsx. | |
| * | |
| * @see https://www.npmjs.com/package/clsx. | |
| */ | |
| @Directive({ | |
| selector: '[clsx]', | |
| }) | |
| export class ClsxDirective implements OnChanges { | |
| @Input('clsx') public clsx: ClassValue[]; | |
| /** Initial component / tag classes */ | |
| private _initialClasses = ''; | |
| /** Necessary in order not to duplicate classes after theme changes */ | |
| private _prevClasses: string; | |
| public constructor( | |
| private elRef: ElementRef, | |
| ) { } | |
| public ngOnChanges(): void { | |
| this.renderClasses(); | |
| } | |
| /** Converts input value into classes and attaches to element */ | |
| private renderClasses(): void { | |
| const classes = clsx(this.clsx); | |
| this._initialClasses = this.elRef.nativeElement.className; | |
| if (this._prevClasses && this._initialClasses) { | |
| const prev = this._prevClasses.split(' '); | |
| prev.forEach((item) => { this._initialClasses = this._initialClasses.replace(item, '').replace(/\s+/gi, ' ').trim(); }); | |
| } | |
| this.elRef.nativeElement.className = `${this._initialClasses} ${classes}`; | |
| this._prevClasses = classes; | |
| } | |
| } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment