[jquery] Jquery sortable 'change' event element position

Is there way to get current position of helper being dragged on over new position ?

$("#sortable").sortable({
        start: function (event, ui) {
            var currPos1 = ui.item.index();
        },
        change:  function (event, ui) {
            var currPos2 = ui.item.index();
        }
});

It seems that currPos1 and currPos2 have same value when actual change happens !

What I need to achieve is highlight to user all positions between 'start drag element' to 'currently replaced element'. Once user releases mouse button update happens and only then I get new position, but I need it before mouse release.

This question is related to jquery jquery-ui-sortable

The answer is


This works for me:

start: function(event, ui) {
        var start_pos = ui.item.index();
        ui.item.data('start_pos', start_pos);
    },
update: function (event, ui) {
        var start_pos = ui.item.data('start_pos');
        var end_pos = ui.item.index();
        //$('#sortable li').removeClass('highlights');
    }

Use update, stop and receive events, check it over here

Jquery Sortable Update Event can called only one time?


If anyone is interested in a sortable list with a changing index per listitem (1st, 2nd, 3th etc...:

http://jsfiddle.net/aph0c1rL/1/

$(".sortable").sortable(
{
  handle:         '.handle'
, placeholder:    'sort-placeholder'
, forcePlaceholderSize: true
, start: function( e, ui )
{
    ui.item.data( 'start-pos', ui.item.index()+1 );
}
, change: function( e, ui )
  {
      var seq
      , startPos = ui.item.data( 'start-pos' )
      , $index
      , correction
      ;

      // if startPos < placeholder pos, we go from top to bottom
      // else startPos > placeholder pos, we go from bottom to top and we need to correct the index with +1
      //
      correction = startPos <= ui.placeholder.index() ? 0 : 1;

      ui.item.parent().find( 'li.prize').each( function( idx, el )
      {
        var $this = $( el )
        , $index = $this.index()
        ;

        // correction 0 means moving top to bottom, correction 1 means bottom to top
        //
        if ( ( $index+1 >= startPos && correction === 0) || ($index+1 <= startPos && correction === 1 ) )
        {
          $index = $index + correction;
          $this.find( '.ordinal-position').text( $index + ordinalSuffix( $index ) );
        }

      });

      // handle dragged item separatelly
      seq = ui.item.parent().find( 'li.sort-placeholder').index() + correction;
      ui.item.find( '.ordinal-position' ).text( seq + ordinalSuffix( seq ) );
} );

// this function adds the correct ordinal suffix to the provide number
function ordinalSuffix( number )
{
  var suffix = '';

  if ( number / 10 % 10 === 1 )
  {
    suffix = "th";
  }
  else if ( number > 0 )
  {

    switch( number % 10 )
    {
      case 1:
        suffix = "st";
        break;
      case 2:
        suffix = "nd";
        break;
      case 3:
        suffix = "rd";
        break;
      default:
        suffix = "th";
        break;
    }
  }
  return suffix;
}

Your markup can look like this:

<ul class="sortable ">
<li >        
    <div>
        <span class="ordinal-position">1st</span>
         A header
    </div>
    <div>
        <span class="icon-button handle"><i class="fa fa-arrows"></i></span>
    </div>
    <div class="bpdy" >
        Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod
    </div>
</li>
 <li >        
    <div>
        <span class="ordinal-position">2nd</span>
         A header
    </div>
    <div>
        <span class="icon-button handle"><i class="fa fa-arrows"></i></span>
    </div>
    <div class="bpdy" >
        Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod
    </div>
</li>
etc....
</ul>

$( "#sortable" ).sortable({
    change: function(event, ui) {       
        var pos = ui.helper.index() < ui.placeholder.index() 
            ? { start: ui.helper.index(), end: ui.placeholder.index() }
            : { start: ui.placeholder.index(), end: ui.helper.index() }

        $(this)
            .children().removeClass( 'highlight' )
            .not( ui.helper ).slice( pos.start, pos.end ).addClass( 'highlight' );
    },
    stop: function(event, ui) {
        $(this).children().removeClass( 'highlight' );
    }
});

FIDDLE

An example of how it could be done inside change event without storing arbitrary data into element storage. Since the element where drag starts is ui.helper, and the element of current position is ui.placeholder, we can take the elements between those two indexes and highlight them. Also, we can use this inside handler since it refers to the element that the widget is attached. The example works with dragging in both directions.