[Sommaire] [Imprimer]

   1  /**
   2   * Javascript library to handle a set of keybindings.
   3   *
   4   * The user should include this script, and then call setKeybinding(key,
   5   * callback) for each keybinding that is desired. This script will take care
   6   * of listening for keypresses and mapping them to the callback functions, or
   7   * doing nothing if no callback is set.
   8   *
   9   * $Horde: horde/templates/javascript/keybindings.js,v 1.5.4.6 2006/03/24 16:05:24 chuck Exp $
  10   *
  11   * See the enclosed file COPYING for license information (LGPL). If you did
  12   * not receive this file, see http://www.fsf.org/copyleft/lgpl.html.
  13   *
  14   * @package Horde
  15   */
  16  
  17  /**
  18   * A hash of keybindings.
  19   *
  20   * @var _keyMap
  21   */
  22  var _keyMap = new Array();
  23  
  24  /**
  25   * Set up the keypress listener.
  26   */
  27  if (typeof document.captureEvents != 'undefined') {
  28      document.captureEvents(Event.KEYPRESS);
  29      document.onkeypress = keyHandler;
  30  } else {
  31      document.onkeydown = keyHandler;
  32  }
  33  
  34  /**
  35   * Sets up a callback for a keycode.
  36   *
  37   * @param key       The keycode to trigger on.
  38   * @param callback  The function to call when "key" is pressed. Should be a
  39   *                  function. It gets the event and the keycode as parameters,
  40   *                  so that you can use one function to handle multiple keys if
  41   *                  you like.
  42   */
  43  function setKeybinding(key, callback)
  44  {
  45      if (typeof _keyMap[key] == 'undefined') {
  46          _keyMap[key] = [];
  47      }
  48  
  49      if (typeof callback == 'function') {
  50          _keyMap[key].push(callback);
  51      } else {
  52          _keyMap[key].push(new Function('e', 'key', callback + '(e, key);'));
  53      }
  54  }
  55  
  56  /**
  57   * Invoked by the JavaScript event model when a key is pressed. Gets
  58   * the keycode (attempts to handle all browsers) and looks to see if
  59   * we have a handler defined for that key. If so, call it.
  60   *
  61   * @param e  The event to handle. Should be a keypress.
  62   */
  63  function keyHandler(e)
  64  {
  65      var e = e || window.event;
  66  
  67      if (e.keyCode) {
  68          key = e.keyCode;
  69      } else if (e.which) {
  70          key = e.which;
  71      }
  72  
  73      /* If there's a handler defined for the key that was pressed, call
  74       * it, passing in the keycode and the event. */
  75      if (_keyMap[key]) {
  76          for (var i = 0; i < _keyMap[key].length; ++i) {
  77              if (_keyMap[key][i](e, key)) {
  78                  e.returnValue = false;
  79                  if (typeof e.preventDefault == 'function') {
  80                      e.preventDefault();
  81                  } else {
  82                      e.returnValue = true;
  83                  }
  84                  break;
  85              }
  86          }
  87      }
  88  }