Loading Indicators

Loading Indicators: free step-by-step lesson with examples, common mistakes, and interview tips — part of jQuery Tutorial on Toolliyo Academy.

8 min read Updated 8/23/2026

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jQuery Tutorial · Lesson 47 of 100

Loading Indicators

Setup & DOM ✓ → Events Effects AJAX → Perf & Integrate → Ship & Projects

Events Effects AJAX · 2 — Interact · ~6 min · AJAX and APIs

What is this?

Show a spinner or aria-busy state when a request starts; clear it in .always(). Disable the triggering button to prevent double submits.

Why should you care?

QueryVerse users on slow 4G need proof that Save is working.

See it live — copy this example

Examples include the jQuery 3.7 CDN. Paste into an HTML file or use Run Example to preview.

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>QueryVerse</title>
  <style>
    body { font-family: system-ui, sans-serif; margin: 1.25rem; }
    .box { padding: .75rem; border: 1px solid #ccc; border-radius: 8px; margin: .5rem 0; }
    .muted { color: #666; }
    button { margin-right: .35rem; margin-top: .35rem; }
    input, select, textarea { margin: .25rem 0; }
    table { border-collapse: collapse; width: 100%; }
    th, td { border: 1px solid #ddd; padding: .4rem .55rem; text-align: left; }
    .hidden { display: none; }
    .row-odd { background: #f7f7f7; }
    .active { font-weight: 700; }
    .toast { background: #111; color: #fff; padding: .5rem .75rem; border-radius: 6px; }
  </style>
</head>
<body>
  <button type="button" id="load">Refresh posts</button>
  <span id="spin" class="muted hidden">Loading…</span>
  <ul id="list" class="box"></ul>
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<script>
$(function () {
  $('#load').on('click', function () {
    var $btn = $(this).prop('disabled', true);
    $('#spin').removeClass('hidden');
    $('#list').attr('aria-busy', 'true');
    $.getJSON('https://jsonplaceholder.typicode.com/posts?_limit=3')
      .done(function (rows) {
        var $list = $('#list').empty();
        rows.forEach(function (r) {
          $list.append($('<li/>').text(r.title));
        });
      })
      .fail(function () {
        $('#list').text('Refresh failed');
      })
      .always(function () {
        $btn.prop('disabled', false);
        $('#spin').addClass('hidden');
        $('#list').attr('aria-busy', 'false');
      });
  });
});
</script>
</body>
</html>

Run Example »

Edit the code below and click Run to see the result in Toolliyo’s live editor.

Code

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>QueryVerse</title>
  <style>
    body { font-family: system-ui, sans-serif; margin: 1.25rem; }
    .box { padding: .75rem; border: 1px solid #ccc; border-radius: 8px; margin: .5rem 0; }
    .muted { color: #666; }
    button { margin-right: .35rem; margin-top: .35rem; }
    input, select, textarea { margin: .25rem 0; }
    table { border-collapse: collapse; width: 100%; }
    th, td { border: 1px solid #ddd; padding: .4rem .55rem; text-align: left; }
    .hidden { display: none; }
    .row-odd { background: #f7f7f7; }
    .active { font-weight: 700; }
    .toast { background: #111; color: #fff; padding: .5rem .75rem; border-radius: 6px; }
  </style>
</head>
<body>
  <button type="button" id="load">Refresh posts</button>
  <span id="spin" class="muted hidden">Loading…</span>
  <ul id="list" class="box"></ul>
<script src="https://code.jquery.com/jquery-3.7.1.min.js"></script>
<script>
$(function () {
  $('#load').on('click', function () {
    var $btn = $(this).prop('disabled', true);
    $('#spin').removeClass('hidden');
    $('#list').attr('aria-busy', 'true');
    $.getJSON('https://jsonplaceholder.typicode.com/posts?_limit=3')
      .done(function (rows) {
        var $list = $('#list').empty();
        rows.forEach(function (r) {
          $list.append($('<li/>').text(r.title));
        });
      })
      .fail(function () {
        $('#list').text('Refresh failed');
      })
      .always(function () {
        $btn.prop('disabled', false);
        $('#spin').addClass('hidden');
        $('#list').attr('aria-busy', 'false');
      });
  });
});
</script>
</body>
</html>

Result