resources/jquery/jquery.tabIndex.js

   1 /**
   2  * jQuery tabIndex
   3  */
   4 ( function( $ ) {
   5 /**
   6  * Finds the lowerst tabindex in use within a selection
   7  *
   8  * @return number Lowest tabindex on the page
   9  */
  10 $.fn.firstTabIndex = function() {
  11         var minTabIndex = null;
  12         $(this).find( '[tabindex]' ).each( function() {
  13                 var tabIndex = parseInt( $(this).prop( 'tabindex' ), 10 );
  14                 // In IE6/IE7 the above jQuery selector returns all elements,
  15                 // becuase it has a default value for tabIndex in IE6/IE7 of 0
  16                 // (rather than null/undefined). Therefore check "> 0" as well.
  17                 // Under IE7 under Windows NT 5.2 is also capable of returning NaN.
  18                 if ( tabIndex > 0 && !isNaN( tabIndex ) ) {
  19                         // Initial value
  20                         if ( minTabIndex === null ) {
  21                                 minTabIndex = tabIndex;
  22                         } else if ( tabIndex < minTabIndex ) {
  23                                 minTabIndex = tabIndex;
  24                         }
  25                 }
  26         } );
  27         return minTabIndex;
  28 };
  29
  30 /**
  31  * Finds the highest tabindex in use within a selection
  32  *
  33  * @return number Highest tabindex on the page
  34  */
  35 $.fn.lastTabIndex = function() {
  36         var maxTabIndex = null;
  37         $(this).find( '[tabindex]' ).each( function() {
  38                 var tabIndex = parseInt( $(this).prop( 'tabindex' ), 10 );
  39                 if ( tabIndex > 0 && !isNaN( tabIndex ) ) {
  40                         // Initial value
  41                         if ( maxTabIndex === null ) {
  42                                 maxTabIndex = tabIndex;
  43                         } else if ( tabIndex > maxTabIndex ) {
  44                                 maxTabIndex = tabIndex;
  45                         }
  46                 }
  47         } );
  48         return maxTabIndex;
  49 };
  50 } )( jQuery );