How to add / use default icons to navigation bar

You can use UIBarButtonSystemItem this way:

let button = UIBarButtonItem(barButtonSystemItem: UIBarButtonSystemItem.Refresh, target: self, action: "someAction")
navigationItem.leftBarButtonItem = button

Result for leftBarButtonItem:

If you want to set it at right side you can use this code:

navigationItem.rightBarButtonItem = button

Result for rightBarButtonItem:

Swift: These are the most commonly used options:

To Use custom image with original colour:

let customImageBarBtn1 = UIBarButtonItem(
    UIImage(named: "someImage.png").withRenderingMode(.alwaysOriginal),
    style: .plain, target: self, action: #selector(handleClick))

To Use custom image with tint colour:

let customImageBarBtn2 = UIBarButtonItem(
    UIImage(named: "someImage.png").withRenderingMode(.alwaysTemplate),
    style: .plain, target: self, action: #selector(handleClick))

Or use system provided buttons:

let systemBarBtn = UIBarButtonItem(
    barButtonSystemItem: .search,
    target: self, action: #selector(handleClick))

Then add any one of these buttons to the navigationItem:

navigationItem.leftBarButtonItems = [customImageBarBtn1, customImageBarBtn2]
navigationItem.rightBarButtonItems = [systemBarBtn]
// OR you can use this if there's only one item.
navigationItem.rightBarButtonItem = systemBarBtn

For custom Images: As a starting size, 22ptx22pt images work well for the default iPhone Navigation Bar size.

In swift 4.3

let btnRefresh = UIBarButtonItem(barButtonSystemItem: UIBarButtonItem.SystemItem.refresh, target: self, action: #selector(targeted function to invoke))

   //If you want icon in left side
    navigationItem.leftBarButtonItem = btnRefresh

   //If you want icon in right side
    navigationItem.rightBarButtonItem = btnRefresh