Swift - How to check if TableView is empty

In Swift 3:

if tableView.visibleCells.isEmpty {
    //tableView is empty. You can set a backgroundView for it.
} else {
    //do something
}

You should check taskMgr.tasks.count value.

func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int{
    if taskMgr.tasks.count == 0 {
       //table view is empty here
    }
    return taskMgr.tasks.count    
}