Check out example codes for "swift how to change the header color". It will help you in understanding the concepts better.

Code Example 1

func tableView(tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
    let returnedView = UIView(frame: CGRectMake(x, y, width, height)) //set these values as necessary
    returnedView.backgroundColor = UIColor.lightGrayColor()

    let label = UILabel(frame: CGRectMake(labelX, labelY, labelWidth, labelHeight))
    label.text = self.sectionHeaderTitleArray[section]
    returnedView.addSubview(label)

    return returnedView
}

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