Dynamic component

To create a dynamic component, such as a popup, use *ngIf:

@Compoent({
    seletor: 'popup',
    // ...
})
export class PopupComponent {
    @Input() message = "";
    @Output() onClose = new EventEmitter<void>();

    onCloseFn () {
        this.close.emit()
    }
}

<popup
    *ngIf="hasError"
    [message]="some error"
    (onClose)="closePopup()">
</popup>

closePopup() {
    this.hasError = false;
}