title: jQuery -.on("click") Not Working on Mobile
body: <p>I have a form that user can upload a file to the database. Unable to make <code>.on("click")</code> event on mobile device. It works fine on pc/laptop and the file is uploaded successful. On mobile, if I click the button, there is no response.</p>
  
  <p><strong>Codes</strong></p>
  
  <pre><code>$(document).on("click", "#submit_upload", function(){
      var data = new FormData(document.querySelector("#fileInfo"));
      // If I comment below variables, 
      // it works fine on both mobile and computers.
      jab = data.get('jab'),
      kat_doc = data.get('jenis_fail'),
      doc_nama = data.get('nama'); 
      doc = data.get('file').size;
  
      $.ajax({
          url: url, 
          type: "POST",                   
          data: data,                     
          contentType: false,         
          cache: false,               
          processData:false,              
          success: function(data)         
          {
              $("#cont").html(data);
  
              if (!doc_nama) {
                  $("#nama-doc").addClass("list-group-item list-group-item-warning");
              }
  
              if (jab == 0) {
                  $("#jab").addClass("list-group-item list-group-item-warning");
              }
  
              if (kat_doc == 0) {
                  $("#kat-doc").addClass("list-group-item list-group-item-warning");
              }
  
              if (!doc) {
                  $("#doc").addClass("list-group-item list-group-item-warning");
              }
  
              $('#myModal').modal({backdrop: "static"});
              $('#myModal').on('shown.bs.modal', function () {
                  $('#myInput').focus();
              });
  
          }
      });
  
  });
  </code></pre>
  
  <p><strong>Note:</strong> If I comment the variables <code>jab/kat_doc/doc_nama/doc</code>, it trigger the click event. </p>
  
  <p>How do I want it to work with the variables?</p>