Style sheets are included in XML views in the same way as plain HTML. To add further CSS classes to SAPUI5 controls, use the class attribute.
The effect is the same as calling myButton.addStyleClass(...).
#!html <mvc:View controllerName="sap.hcm.Address" xmlns="sap.ui.commons" xmlns:mvc="sap.ui.core.mvc" xmlns:html="http://www.w3.org/1999/xhtml"> <html:style> .mySuperRedButton { color: red; } </html:style> <Panel> <Button class="mySuperRedButton" text="Press Me"/> </Panel> </mvc:View>