javascript - 可排序 - 更新现有数组 - jQuery

Question

我有一个现有的元素数组，例如:

arr=[{名称:1,数据:xyz},{名称:2,数据:abc},{名称:3,数据:lmn}; {名称:4，数据:opq}]

此项目根据其在 UI 上的名称进行填充。 示例:1 2 3 4 5

我已经实现了 jQuery 的 Sortable。我希望在用户对上述元素执行拖放操作后根据元素的新位置更新现有数组 arr，而不是创建新数组。

用户可以移动数组arr中存在的元素，并且不能从1 2 3 4 5元素列表外部引入任何拖动的对象，例如:2可以移动到 5 或 1 可以移动到 3 等等。

HTML 元素:

<ul class= "tree-list">
 <li class="li_class"><span class="span_class"> 1 </span></li>
 <li class="li_class"><span class="span_class"> 2 </span></li>
 <li class="li_class"><span class="span_class"> 3 </span></li>
 <li class="li_class"><span class="span_class"> 4 </span></li>
 <li class="li_class"><span class="span_class"> 5 </span></li>
</ul>

jQuery:

 $(function() {
            var data = $(".tree-list").sortable({
              delay: 150,
              axis: "y",
      
            update: function(event, ui) {
                var index = ui.item.index();
                console.log("Moved to new position: " + index);
                var children = $('ul.tree-list').children()
                // What to do here
           
            })
     
            $( ".tree-list" ).disableSelection();
        });

动态创建的数组:

someFunc(data){
    let htmlString= " <ul class =\"tree-list\" "
    for (let i=0; i<data.length; i++){
        if(typeof(item) === "string"){
          htmlString += "<li class=\" li_class \"" + item + "\">";
                                     }
        else if(typeof(item) === "object"){
          htmlString += "<li>";
          htmlString += "span class=\"span_class\""  
                                     }
           htmlString += "</li>"
                                   }
       }
htmlString += "</ul>";
return (htmlString);

}

Answer 1

我尝试使用初始数组重新创建您的示例:

我所做的是，首先创建data-previndex来使用start srotable存储li位置更新上的先前索引:(归功于此answer)

然后每次更新时，调用 array_move (归功于此 answer )，根据先前和当前的索引更新 js 数组上的元素

请参阅下面的工作片段:

$(function() {
  let arr = [{name:1,data:"xyz"}, {name:2,data:"abc"}, {name:3, data:"lmn"}, {name:4,data:"opq"}, {name:5,data:"stu"}]
  
  let $treeList = $(".tree-list");
  
  arr.forEach(element => {
    let liNode = `<li class="li_class"><span class="span_class"> ${element.name} </span></li>`
    $treeList.append(liNode);
  })
   
  var data = $(".tree-list").sortable({
    delay: 150,
    axis: "y",
    start: function(e, ui) {
        // creates a temporary attribute on the element with the old index
        // credits to this answer https://stackoverflow.com/questions/1601827/jquery-ui-sortable-how-to-determine-current-location-and-new-location-in-update
        $(this).attr('data-previndex', ui.item.index());
    },

    update: function(event, ui) {
      var newIndex = ui.item.index();
      var oldIndex = $(this).attr('data-previndex');
      
      
      var children = $('ul.tree-list').children()
      // What to do here
      arr = array_move(arr, oldIndex, newIndex);
      console.clear()
      console.log(JSON.stringify(arr));
    }
  });

  $(".tree-list").disableSelection();
});

function array_move(arr, old_index, new_index) {
    if (new_index >= arr.length) {
        var k = new_index - arr.length + 1;
        while (k--) {
            arr.push(undefined);
        }
    }
    arr.splice(new_index, 0, arr.splice(old_index, 1)[0]);
    return arr; 
};

@import url("https://code.jquery.com/ui/1.12.0/themes/smoothness/jquery-ui.css");

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://code.jquery.com/ui/1.12.0/jquery-ui.min.js"></script>
<ul class="tree-list">
</ul>