How to use the @alfresco/adf-core.FormEvent function in @alfresco/adf-core

protected onTaskSaved(form: FormModel) {
        this.formSaved.emit(form);
        this.formService.taskSaved.next(new FormEvent(form));
    }

protected onFormLoaded(form: FormModel) {
        this.formLoaded.emit(form);
        this.formService.formLoaded.next(new FormEvent(form));
    }

protected onTaskCompleted(form: FormModel) {
        this.formCompleted.emit(form);
        this.formService.taskCompleted.next(new FormEvent(form));
    }

protected onFormDataRefreshed(form: FormModel) {
        this.formDataRefreshed.emit(form);
        this.formService.formDataRefreshed.next(new FormEvent(form));
    }