TabBar.Item

name	description	type	default
icon	icon of the tab	number
iconColor	icon tint color	string
iconSelectedColor	icon selected tint color	string
label	label of the tab	string
labelStyle	custom label style	custom
maxLines	maximun number of lines the label can break	number	1
selectedLabelStyle	custom selected tab label style	custom
selected	whether the tab is selected or not	bool
onPress	callback for when pressing a tab	func
showDivider	whether the tab will have a divider on its right	bool
width	A fixed width for the item	number
onLayout	A callback to invoke for onLayout event	func

See example here.