How to change data attributes on drag and drop Jquery UI?

user_12174711 0
Viewed 191

I made a jQuery function where the user can drag and drop divs. But I want to change their data attributes whenever users drag and drop them, eg-

<div data-num="1">one</div>
<div data-num="2">Two</div>
<div data-num="3">Three</div>
<div data-num="4">Four</div>

Whenever user drag div three and place it on the top then it should change its data attribute data-num="3" to data-num="1" and the div after it should change its data attribute to data-num=2 and so on according to their position

What I am Trying

jQuery( "#app" ).sortable({ 
    update: function(a, b) { 
        parseInt(jQuery(a).attr("data-num"),10) - parseInt(jQuery(b).attr("data-num"),10);
    }          
});
jquery-ui-sortable jquery javascript
2 Answers

To achieve your goal you can hook an event handler to the stop event of the sortable. Then you can loop through each child div in #app and update the data-num to match the index of the element. Try this:

jQuery($ => {
  $("#app").sortable({
    stop: () => {
      $('#app > div').each((i, el) => $(el).data('num', i + 1));
    }
  });

  // only for testing...
  $('button').on('click', () => {
    $('#app > div').each((i, el) => console.log(`${el.textContent} - ${$(el).data('num')}`));
  });
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://code.jquery.com/ui/1.12.1/jquery-ui.min.js"></script>
<div id="app">
  <div data-num="1">One</div>
  <div data-num="2">Two</div>
  <div data-num="3">Three</div>
  <div data-num="4">Four</div>
</div>

<button>Test</button>

user_5194130

we can also achieve this by using the item index

jQuery("#app").sortable({
   update: function(e, ui) {
       jQuery("#app div").each(function(i, elm) {
           $elm = jQuery(elm);
           var elindex = $elm.index("#app div");
           $elm.attr("data-num", elindex+1);
       });
    }   
});
user_121747110
Related