title: how i can change the background color of navigationBar
body: <p>In my navigation bar i have two button at left and right position and a segmentetControll view at navigation title.
  I want to change the background color of the navigation bar to black but thae color of the items on it will be another color.
  how can i do it?
  I try to chnage the tintColor of the navigationBar to black.
  but i show that the color of the segmentedControll and the button on the navigationBar also changed to black.</p>
  
  <p>thanks in advance.</p>