Loading screen not displaying correctly

I am trying to create a loading screen that preloads a large amount of text data from various text files into a dictionary.  I am using scenes, having main load a static background then transfer to the loading scene.  The loading scene is supposed to store the data using a loop, periodically updating a series of images indicating the loading progress.  However, the images are not displaying until the data loop has completely finished, even though console printouts still update correctly.  I had this problem when attempting to do this all in main, hence the attempt to do it with scenes.

The basic outline of the code is:

for x = 1, eachDataItem do

    storeCurrentData(x)

    if certainCriteria == true then

        updateDisplay()

        print(certainCriteria)

    end

end

The data stores correctly, the console printouts print, but the display doesn’t update until the loop has finished. 

Edit: I have come up with 3 possible solutions to sidestep the problem, though I am still curious what is wrong with the original.  

  1. Just use a static loading screen with a warning it may take a while.  

  2. Use an individual scene for each step.  The display should update before transitioning to the new scene.  

  3. Not sure on this one, but maybe load an animated background with main and see if it still updates correctly during the file loading.

Final edit: I went the multiple scene route since I could not get a timely answer, turning the single loading scene into 8 scenes: a preloader, 6 scenes that each do one run of the original loop, and a postloader to clean everything up before transitioning to the menu.  It’s silly and counterintuitive, but it works.