This expression uses the ternary operator to conditionally output one of two values dependent on a condition.
<a class="{!v.location == '/active' ? 'selected' : ''}" href="#/active">Active</a>
The {!v.location == '/active' ? 'selected' : ''} expression conditionally sets the class attribute of an HTML <a> tag, by checking whether the location attribute is set to /active. If true, the expression sets class to selected.
This snippet of markup uses the <aura:if> tag to conditionally display an edit button.
<aura:attribute name="edit" type="Boolean" default="true"/> <aura:if isTrue="{!v.edit}"> <ui:button label="Edit"/> <aura:set attribute="else"> You can’t edit this. </aura:set> </aura:if>
If the edit attribute is set to true, a ui:button displays. Otherwise, the text in the else attribute displays.