title: Javascript and Google sheets interactions
body: <p>I'm new in JavaScript and currently building a web apps that interact with Google Sheets as a database.
  Basically what i'm building right now is to get input from users through Web apps and giving it to the Google Sheets (which have all the database &amp; formulas in it).</p>
  <p>Based on the input, Google sheets will then do the calculation and return back the value to JavaScript to be publish on the Web. (I do this because i want to make the Google Sheets data remain private). Due to the complex dataset, Google Sheet will take some time (around 3-5 seconds) before can pass the value to Javascripts (using SuccessHandler).</p>
  <p>The code that i currently have is working ok. But i want to make the Web apps more interactive. What i means is that, during the data processing by the Google Sheets, i want to tell the user to 'hold on' and don't do anything yet. I try to use loader but I don't know how to trigger &amp; to stop the loader (while waiting Google Sheets do the calculation process).</p>
  <p>Would greatly appreciate if someone could help me in this problem.</p>
  <p>thanks.</p>