title: ios: why not use just ONE view controller for every app
body: <p>This may sound a bit strange: Since there is only one screen visible at a give time why not use a single view controller and regenerate view hierachy/content by allocating,adding, destroying subviews programmatically as needed?</p>
  
  <p>I'm porting a VOIP SW that runs on a hardware phone. The hw phone has a touch sreen. The touch screens contents are created by a core module that provides instructions to the rendering module displaying these on the touch screen (createscreen,createbutton, createtextfield,..,destroyscreen, destroybutton,..).Naturally, the module managing the screen layout being part of the core voip sw,runs on it's own thread. It would therefore be necessary to create/destroy views in the background and push them on the main thread for display.
  Since all the screens/subscreens items are known, i prefer the classic approach (storyboard,xib,additional code where needed) and match the incoming draw request to the layout items, thus just updating the data. Allocating/destroying all these view structures seems a performance nightmare to me as well, but i have been hard pressed to dynamically do it.
  I need your help in reasoning against it.  </p>