layui 二级联动菜单

<form class="layui-form" action="{empty name="id"}{:url('add')}{else /}{:url('edit')}{/empty}" method="post" enctype="multipart/form-data" >

  <div class="layui-form-item">
    <label class="layui-form-label">栏目</label>
    <div class="layui-input-block">
      {volist name="menu_rs" id="vo"}
           <input type="checkbox" name="category[]" value="{$vo.id}" title="{$vo.title}" {if in_array($vo.id,$category_arr)}checked{/if}>
        {/volist}
    </div>
  </div>
  <div class="layui-form-item">
    <label class="layui-form-label">标题</label>
    <div class="layui-input-block">
      <input type="text" name="title" value="{$rs.title}" lay-verify="required" placeholder="输入标题" autocomplete="off" class="layui-input" >
    </div>
  </div>
  <div class="layui-form-item">
        <label class="layui-form-label">封面</label>
        <div class="layui-input-block">
          <input type="file" name="image[]" />
            {if $rs.img }
            <a href="/uploads/{$rs.img}" target="_blank"><img style="float:left;" src="/uploads/{$rs.img}" width="30" height="30px"></a>
            {/if}
            PC banner尺寸：高度420px(最佳尺寸:1920px*420px),大小300K以内;APP、小程序banner尺寸：750px*330px;APP、小程序引导图片尺寸:750px*1334px
<!--<input type="file" name="image[]" /> <br> 
<input type="file" name="image[]" /> <br>-->
        </div>
  </div>
  <div class="layui-form-item layui-form-text">
    <label class="layui-form-label">简介</label>
    <div class="layui-input-block">
      <textarea name="description" placeholder="请输入内容" class="layui-textarea">{$rs.description}</textarea>
    </div>
  </div>
  <div class="layui-form-item">
      <label class="layui-form-label">类型</label>
      <div class="layui-input-block">
        <input type="radio" name="type" lay-filter="type" value="0" title="PC" {if $rs.type==0}checked{/if}>
        <input type="radio" name="type" lay-filter="type" value="1" title="APP/小程序" {if $rs.type==1}checked{/if}>
      </div>
  </div>
  
 <div class="layui-form-item" id="pc_url">
      <label class="layui-form-label">URL链接</label>
      <div class="layui-input-block">
        <input type="text" name="url" value="{$rs.url}" placeholder="输入链接" autocomplete="off" class="layui-input" >
      </div>
 </div>
 <a href="../../pages/News/details?id=123"></a>
  <div class="layui-form-item" id="app_url" style="display: none;">
    <div class="layui-inline">
      <label class="layui-form-label">URL链接</label>
      <div class="layui-input-inline">
        <select name="url1" lay-filter="url1" lay-verify="required">
          <option value="">链接到栏目</option>
          {volist name="menu_rs" id="vo"}
          <option value="{$vo.id},{$vo.controller}">{$vo.title}</option>
          {/volist}
        </select>
      </div>
    </div>
    <div class="layui-inline">
      <label class="layui-form-label">落地页</label>
      <div class="layui-input-inline">
        <select name="url2" id="url2" >
           <option value="">链接到具体网页</option>
        </select>
      </div>
    </div>
  </div>

  <div class="layui-form-item">
    <div class="layui-inline">
      <label class="layui-form-label">打开方式</label>
      <div class="layui-input-inline">
        <input type="radio" name="state" value="0" title="新窗口" {if $rs.state==0}checked{/if}>
        <input type="radio" name="state" value="1" title="自身" {if $rs.state==1}checked{/if}>
      </div>
    </div>
    <div class="layui-inline">
      <label class="layui-form-label">状态</label>
      <div class="layui-input-inline">
        <input type="radio" name="hide" value="0" title="显示" {if $rs.hide==0}checked{/if}>
        <input type="radio" name="hide" value="1" title="隐藏" {if $rs.hide==1}checked{/if}>
      </div>
    </div>
    <div class="layui-inline">
      <label class="layui-form-label">排序</label>
      <div class="layui-input-inline">
        <input type="text" name="sort" value="{$rs.sort}" autocomplete="off" class="layui-input">
      </div>
    </div>
  </div>

  
  <div class="layui-form-item">
    <div class="layui-input-block">
      <button class="layui-btn" lay-submit lay-filter="formDemo">立即提交</button>
      <button type="reset" class="layui-btn layui-btn-primary">重置</button>
    </div>
  </div>
       <input type="hidden" name="id" value="{$id}">
</form>

<script>
layui.use(['element','form','jquery'], function(){
  var form = layui.form
  ,element = layui.element
  ,$= layui.$;
      
      form.on('radio(type)', function(data){ 
//          console.log(data.value); //被点击的radio的value值
        
          if(data.value == 1){
            $("#app_url").show();
            $("#pc_url").hide();
          }else{
            $("#pc_url").show();
            $("#app_url").hide();
            
          }
      }); 
      
      form.on('select(url1)', function(data){
         //console.log(data.value); //得到被选中的值
               $("#url2").find("option").remove();
         var data = myData(data.value);
         $("#url2").append(data);
         form.render('select');
         
         //console.log(data);
      });   
  
      function myData(id) {
            var data1 ;
            $.ajax({
                url:'{:url('index')}',
                type:"post",
                data:{action:'jsondata',listid:id},
                async:false,
                success:function(data){
                  data1 = data;
                  //data1 = JSON.parse(data);
                  //console.log(data1);
                },
                error:function(){
                  layer.msg('读取数据失败！');
                }
            });
             return data1;
      }


});
</script>

控制器代码

    if($action=='jsondata' && $listid){
      //网址格式
      //具体落地网页  ../../pages/News/details?id=123
      //列表  ../../pages/News/index
      $idarr = explode(',',$listid);
      if(count($idarr)==2){
        $returndata="<option value='1'>北京</option><option value='2'>北京2</option>";
      }
      return $returndata;
      
    }

控制器返回数据格式：

$returndata="<option value='1'>北京</option><option value='2'>北京2</option>";