Document.hasFocus()

Baseline Widely available

This feature is well established and works across many devices and browser versions. Itâs been available across browsers since 2015ë 7ì.

Document.hasFocus() ë©ìëë ë¬¸ì ëë ë¬¸ì ë´ì ìì(element) ì¤ ì´ë íëë¼ë í¬ì»¤ì¤(focus)ë¥¼ ê°ê³ ìì¼ë©´ true, ê·¸ë ì§ ìì¼ë©´ false ì¸ Boolean ê°ì ë°ííë¤. ì´ ë©ìëë¥¼ ì¬ì©íì¬ ë¬¸ìë´ íì±íë(active) ììê° í¬ì»¤ì¤ë¥¼ ê°ê³ ìëì§ íë¨í ì ìë¤.

ì°¸ê³ : ë¬¸ìë¥¼ ë³¼ ë, í¬ì»¤ì¤ë¥¼ ê°ì§ ììë ì¸ì ë ë¬¸ììì íì±íë ììì´ë¤. ë°ë©´ì íì±íë ììë ê¼ í¬ì»¤ì¤ë¥¼ ê°ì§ ìì ì ë ìë¤. ìë¥¼ ë¤ë©´ ì ë©´ì ëììì§ ìì(not a foreground) íìì°½ ë´ì íì±íë ììë í¬ì»¤ì¤ë¥¼ ê°ê³ ìì§ ìë¤.

êµ¬ë¬¸

focused = document.hasFocus();

ë°í ê°

ìì

html

<!doctype html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <title>TEST</title>
    <style>
      #message {
        font-weight: bold;
      }
    </style>

    <script>
      setInterval(CheckPageFocus, 200);

      function CheckPageFocus() {
        var info = document.getElementById("message");

        if (document.hasFocus()) {
          info.innerHTML = "The document has the focus.";
        } else {
          info.innerHTML = "The document doesn't have the focus.";
        }
      }

      function OpenWindow() {
        window.open(
          "http://developer.mozilla.org/",
          "mozdev",
          (width = 640),
          (height = 300),
          (left = 150),
          (top = 260),
        );
      }
    </script>
  </head>

  <body>
    <h1>JavaScript hasFocus example</h1>
    <div id="message">Waiting for user action</div>
    <div><button onclick="OpenWindow()">Open a new window</button></div>
  </body>
</html>