How to create a heartbeat activity view for a single group

This is a short guideline in steps on how i render a view showing the activity for a given group (url arguments).

1. Add a view, naming it and choosing "heartbeat activity" as base data type. Next.
2. Give your view a title, add a block display and give it an administration name. 
3. Add two fields: "heartbeat message" and the "time of the activity".  The view already renders all of the activity.
4. Add filter: "Heartbeat activity: Heartbeat user access" and choose "Organic group activity" from the dialog box.
5. Save the view.That's it

This approach will make sure this block detects the group node id on the group page or a group post page. On all other pages, it will return the of nodes where no nid is found, so the result of "( heartbeat_activity.nid = 0 OR heartbeat_activity.nid_target = 0 )".
So this is usable on the group page and group post page only!

If you want to create advanced views, you could work without the filter (omit step 4 and 5) and create your argument yourself.