title: Update GUI simultaneously during event handler using wxpython
body: <p>I have written some code on a GUI which when a button is pressed runs a really long process that sorts out images and processes them. However, I have a textCtrl(text box) which the stdout is redirected to the text box. My issue is that the textbox does not update during the event and only after the event is finished then updates all in one go. </p>
  
  <p>I have tried a few solutions such as threading, multiprocessing(best hope yet), wx.callafter, but still I don't quite understand how is best to proceed. please do let me know if u have any idea what would be the best way. I would post the code but it is currently 800 lines long so not sure how useful it would be. Any help would be appreciated.</p>