onCheckStepActivation(oEvent) {
			this._clearMessages();
			const sWizardStepId = oEvent.getSource().getId();
			switch (sWizardStepId) {
				case this.createId("creditCardStep"):
					this.checkCreditCardStep();
					break;
				case this.createId("cashOnDeliveryStep"):
					this.checkCashOnDeliveryStep();
					break;
				case this.createId("invoiceStep"):
					this.checkInvoiceStep();
					break;
				case this.createId("deliveryAddressStep"):
					this.checkDeliveryAddressStep();
					break;
				default:
					break;
			}
		}
Checks the corresponding step after activation to decide whether the user can proceed or needs
to correct the input
@param {sap.ui.base.Event} oEvent Event object