pm-controls/source/app/controls/components/expander/expander.html

ProModel Controls

<div class="{{ExpanderClass}}">
    <div class="expander-header" 
         (click)="OnClick()" 
         [class]="ExpanderHeaderClass"
         [class.expander-header-expanded]="IsExpanded">
        <ng-content select="[expander-header]"></ng-content>
        <pm-icon-down-arrow *ngIf="IsExpanded"></pm-icon-down-arrow>
        <pm-icon-right-arrow *ngIf="!IsExpanded"></pm-icon-right-arrow>
    </div>
    <div *ngIf="IsExpanded">
        <ng-content select="[expander-body]"></ng-content>
    </div>
</div>