title: Change the background color of a UIActivityViewController
body: <p>In iOS 7, the standard <code>UIActivityViewController</code> has a transluscent whitish background. On the contrary my app has a dark theme. It looks terrible when the white <code>UIAcitivityViewController</code> pops up on the dark app background.</p>
  <p><strong>Is there a way to change the background color of a</strong> <code>UIAcitivityViewController</code><strong>?</strong></p>
  <p>I have tried
  <code>activityVC.view.backgroundColor = [UIColor blackColor]</code>, but this makes the whole screen black, not just the area occupied by the <code>UIAcitivity</code> icons like the standard white background.</p>
  <p><img src="https://i.stack.imgur.com/KMb5o.png" alt="screenshot of a UIActivityViewController" /></p>