Question

我正在尝试创建一个包含搜索栏，无限滚动产品页面和按钮（添加产品，删除产品和通知）的页面。以下语句有误...

<span id="value" style="margin: 3px;">
    <?php 
      if(get_forum_likes($id_forum, $pdo) < 0){
        echo '<span style="color:#fb3f6c;">'.number(get_forum_likes($id_forum, $pdo))."</span>";
      } elseif(get_forum_likes($id_forum, $pdo) > 0){
        echo '<span style="color:#25804a;">'.number(get_forum_likes($id_forum, $pdo))."</span>";
      } else {
        echo number(get_forum_likes($id_forum, $pdo)); 
    }
    ?>
    </span>                    
    <i id="<?php echo $id_forum; ?>" class="vote_up fas fa-angle-up"></i>

    <script>
    $(document).ready(function(){
        $("i.vote_up").click(function(){

            var value_no = document.getElementById("value");
            var forum_id = $(this).attr('id');
            $.post("game/forum/vote_post.php",
                {
                    forum_id: forum_id,
                    type: 0
                },
                function(res, status){
                    $("#value").html();
                    value_no++
                }
            );
        });
    });
    </script>

请帮助我纠正此代码。

The getter 'visible' was called on null,
Receiver : null, 
Tried calling : null

Answer 1

感谢您的帮助@Mobina和@JohnJoe。我用柔韧性包装了ListView.builder，从而解决了这个问题，并添加了COntainer将其放在灰色背景中。

Widget build(BuildContext context) {
    return Container(
      padding: EdgeInsets.only(top: 10.0, bottom: 10.0),
      height: 450,
      width: 350,
      decoration: BoxDecoration(
          color: Color(0xFF707070),
          borderRadius: BorderRadius.all(
            Radius.circular(
              10.0,
            ),
          )),
      child: Flexible(
        child: ListView.builder(
            controller: _scrollController,
            itemCount: prd.length + 1,
            itemExtent: 42.5,
            itemBuilder: (context, i) {
              if (i == prd.length) {
                return CupertinoActivityIndicator();
              }
              return ListTile(
                title: AutoSizeText(prd[i]),
              );
            }),
      ),
    );
  }

吸气剂“可见”被调用为null

1 个答案: