Angular: conditional class with *ngClass

Question

What is wrong with my Angular code? I am getting:

Cannot read property \'remove\' of undefined at BrowserDomAdapter.removeClass ...

Answer 1

Try Like this..

Define your class with ''

<ol class="breadcrumb">
    <li *ngClass="{'active': step==='step1'}" (click)="step='step1; '">Step1</li>
    <li *ngClass="{'active': step==='step2'}"  (click)="step='step2'">Step2</li>
    <li *ngClass="{'active': step==='step3'}" (click)="step='step3'">Step3</li>
</ol>

Answer 2

You should use something ([ngClass] instead of *ngClass) like that:

<ol class="breadcrumb">
  <li [ngClass]="{active: step==='step1'}" (click)="step='step1; '">Step1</li>
  (...)

Answer 3

Additionally, you can add with method function:

In HTML

<div [ngClass]="setClasses()">...</div>

In component.ts

// Set Dynamic Classes
  setClasses() {
    let classes = {
      constantClass: true,
      'conditional-class': this.item.id === 1
    }

    return classes;
  }

Answer 4

Angular version 2,...,9 provides several ways to add classes conditionally:

type one

[class.my-class]="step === 'step1'"

type two

[ngClass]="{'my-class': step === 'step1'}"

and multiple option:

[ngClass]="{'my-class': step === 'step1', 'my-class2':step === 'step2' }"

type three

[ngClass]="{1:'my-class1',2:'my-class2',3:'my-class4'}[step]"

type four

[ngClass]="(step=='step1')?'my-class1':'my-class2'"

Answer 5

This is what worked for me:

[ngClass]="{'active': dashboardComponent.selected_menu == 'profile'}"

Answer 6

Another solution would be using [class.active].

Example :

<ol class="breadcrumb">
    <li [class.active]="step=='step1'" (click)="step='step1'">Step1</li>
</ol>