Isotope v2 Grid - Multiple Filters - Hide empty filters

问题

My current isotope grid has two dropdown filters that sort the grid items. The first filter is menu type, and the second filter is drink type. Each menu type however does not contain all drink types so when some filter configurations are chosen, no results are showed, which is correct. But i would like to stop this from happening by when the user selects the first filter, the second filter hides the empty types.

Working Codepen of current filters: https://codepen.io/whitinggg/pen/zYGEaNb

This was my old filter code:

// Select Filters
jQuery(function ($) {
    var $grid = $('.grid');
    var $selects = $('div#filterGroup select').change(function() {
        var selector = $selects.get().map(function(el) { // map the select elements ...
            return $(el).val(); // ... to an array of values
        }).join('') || '*'; // if joined array is empty-string, then default to a single '*'
        $grid.isotope({
            'filter': selector
        });
        return false;
    });

    $grid.imagesLoaded().progress( function() {
      $grid.isotope('layout');
    });
  });

I have tried to change my code to the below from other links around the internet on this topic but havent had any luck getting it to work.

// Select Filters
jQuery(function ($) {
    var $grid = $('.grid');
    var $selects = $('div#filterGroup select').change(function() {
        var selector = $selects.get().map(function(el) { // map the select elements ...
            return $(el).val(); // ... to an array of values
        }).join('') || '*'; // if joined array is empty-string, then default to a single '*'
        $grid.isotope({
            'filter': selector
        });
        return false;
    });

//Hide Empty Filters
    var DROP = $('div#filterGroup select option:not([data-filter=""])');
    // list of all class in html
    var strall = ''; $('.grid-item').each(function(el){ strall += $(this).attr('class')  });
    // remove select if not in strall.. TODO : needs improvement, this is kind a hack
    DROP.each(function(el){
      var nowfilter = $(this).attr('data-filter').replace('.', ''); // co_kenya
      if( strall.indexOf( nowfilter ) == -1 ){
        console.log( 'this one is missing ' + nowfilter );
        $(this).remove();
      }
    });

    $grid.imagesLoaded().progress( function() {
      $grid.isotope('layout');
    });
  });

Is this possible? Any help much appreciated!

回答1:

Working codepen

First, add an ID to each drop-down so that we can distinguish them.

<select id="menu-selector" class="filter option-set" data-filter-group="menu">
[...]
<select id="type-selector" class="filter option-set" data-filter-group="categories">

Then, for each drop-down, add a change listener. We'll look at the code for the menu drop-down change listener.

First, get the class filter from the selected drop-down:

 $('#menu-selector').change(function() {
     var selectedClass = $('#menu-selector option:selected').attr('value');

Then we're going to select all of the grid items matching that type, to see what other classes they have. These other classes will be the available types

     var availableTypes = $(`.grid-item${selectedClass}`)
       .toArray()
       .flatMap(div => Array.from(div.classList.values())) //get all of the classes
       .filter(i => !['grid-item', selectedClass.substring(1)].includes(i));  //eliminate useless ones

Last, toggle the disabled property on the other drop-down, enabling only those that are available.

     $('#type-selector option')
         .each( (i,el) => $(el).prop('disabled', el.value != ""  && !availableTypes.includes(el.value.substring(1))));

That should do it. The change handler for the type drop-down is the same but references the opposite drop-down. Check the codepen for details.

来源：https://stackoverflow.com/questions/60549656/isotope-v2-grid-multiple-filters-hide-empty-filters

标签

javascript

jquery

filter

jquery-isotope