I have a xml view fragment which includes a side navigation

```
<SideNavigation id="sideNavigation" expanded="false">
    <item>
        <NavigationList expanded="false">
            <NavigationListItem text="Start" icon="sap-icon://employee" select="initChangeView" expanded="false">
            </NavigationListItem>
            <NavigationListItem text="On Track" icon="sap-icon://building" select="initChangeView" expanded="false">
            </NavigationListItem>
            <NavigationListItem text="Details" icon="sap-icon://employee" select="initChangeView" expanded="false">
            </NavigationListItem>
            <NavigationListItem text="Comparison" icon="sap-icon://employee" select="initChangeView" expanded="false">
            </NavigationListItem>
        </NavigationList>
    </item>

</SideNavigation>

```

I want to add and remove a custom css class when one is of the items is selected.
What I am trying to do is to remove the class "selectedNavItem" from every NavigationListItem and add it to the selected one, but I get the TypeError

> 
> Cannot read property 'removeStyleClass' of undefined
> 
> 
> 

Handler in controller.js: 

```
jQuery.sap.require("xxx.controller.NavigationBar");
[...]
initChangeView: function(oEvent){  
        setExpandedToFalse(this);
        changeView(this, oEvent.getSource());
    },
[...]

```

And my NavigationBar.js:

```
function changeView(controller, source) {
var items = source.getParent().getItems();
console.log(items);
for(i = 0; i < items.length; i++)
{
    items[i].getBindingContext().removeStyleClass("selectedNavItem");
}
source.addStyleClass("selectedNavItem");
[...]

```

Thanks!