微擎app端上传图片后删除不了图片

<!--自己的头部引入-->
{template ‘common_header‘}

<script type="text/javascript" src="{$_W[‘siteroot‘]}app/resource/js/app/util.js"></script>
<script src="{$_W[‘siteroot‘]}app/resource/js/require.js"></script>
<script type="text/javascript" src="{$_W[‘siteroot‘]}app/resource/js/lib/mui.min.js"></script>
<link href="{$_W[‘siteroot‘]}app/resource/css/common.min.css" rel="stylesheet">
<script type="text/javascript" src="{$_W[‘siteroot‘]}app/resource/js/app/common.js"></script>

<form action="" method="post">
    <ul class="report-list white clearfix">
        <li class="clearfix">
            <div class="pull-left">
                标题
            </div>
            <div class="pull-right">
                <input type="text" placeholder="请输入标题" name="report_title" value="">
            </div>
        </li>
        <li class="clearfix">
            <div class="pull-left">
                填写人
            </div>
            <div class="pull-right">
                <input type="text" placeholder="请输入填写人" name="report_author" value="">
            </div>
        </li>
    </ul>
    <button type="button" class="submit-report">提交</button>
    <input type="hidden" name="token" value="{$_W[‘token‘]}" />
</form>

<script type="text/javascript">
    $(function(){
        mui.init({
            swipeBack: true //启用右滑关闭功能
        });

        //上传图片
        util.image($(‘.js-image-report_picture‘), function(url){
            $(‘.js-image-report_picture‘).parent().find(‘.js-image-preview‘).append(‘<input type="hidden" value="‘+url.attachment+‘" name="report_picture[]" /><img src="‘+url.url+‘" data-id="‘+url.id+‘" data-preview-src="" data-preview-group="__IMG_UPLOAD_report_picture" />‘);
        }, {
            crop : false,//裁剪
            multiple : true,//多图
            preview : ‘__IMG_UPLOAD_{$name}‘//预览
        });
    });

</script>

{template ‘common_footer‘}

//删除图片
        $(document).on("click", ".mui-clearfix .js-submit", function (a) {
            var b = $(document).find(".mui-slider-group .mui-active").index();
            $(".mui-image-preview input").eq(b).remove();
            $(".mui-image-preview img").eq(b).remove();
            var i = mui.previewImage({footer: util.templates["image.preview.html"]});
            i.close();
        });