The SelectSKU event is triggered when a user selects specific product attributes (e.g. color, size, etc).
- Both 
groupIdandfeedIdparameters are required to be non-empty otherwise this event will not be tracked. - The 
groupIdrepresents a group of similar items. For example, a shirt will have the samegroupIdfor all variations of that shirt (different sizes/colors, etc). I.e. each size/color combo will have a differentfeedIdbut the samegroupId. 
Implementation
Wunderkind.getInstance().trackSelectSku(String groupId, String feedId, String itemId)Wunderkind.shared.trackSelectSKU(groupId: String, feedId: String, itemId: String)Wunderkind().trackSelectSku(groupId: string, feedId: string, itemId: string)Wunderkind.trackSelectSku(groupId: string, feedId: string, itemId: string)