OpportunityMenu.cmp
<aura:component implements="force:appHostable">
<aura:dependency resource="markup://force:navigateToSObject" type="EVENT"/>
<aura:handler name="init" value="{!this}" action="{!c.navHome}"/>
</aura:component>
OpportunityMenuController.js
({
navHome : function (component, event, helper) {
var homeEvent = $A.get("e.force:navigateToObjectHome");
homeEvent.setParams({
"scope": "Opportunity"
});
homeEvent.fire();
}
})