关于easyui datagrid展开行的问题

悬赏园豆：20 [待解决问题]

第一次加载进来的时候是可以展开的，但是点击“添加”按钮，弹出一个遮罩的Dialog，然后关闭这个Dialog, 这时就不能展开了。附上JS代码

$(function () {
    $.ajaxSetup({ cache: false });
    $.parser.parse();

    $("#dg").datagrid({
        url: $("#rolesUrl").val(),
        toolbar: "#toolbar",
        title: "角色",
        pagination: true,
        rownumbers: false,
        singleSelect: true,
        fitColumns: false,
        width: 668,
        height: 400,
        columns: [[
        { field: "RoleName", title: "角色名", width: 319 },
        { field: "Status", title: "状态", width: 319,
            formatter: function (value, rowData, rowIndex) {
                if (rowData.Status == true) {
                    return "有效";
                }
                else {
                    return "失效";
                }
            }
        }
        ]],
        view: detailview,
        detailFormatter: function (index, row) {
            return '<div id="ddv-' + index + '" style="padding:5px 0"></div>';
        },
        onExpandRow: function (index, row) {
            var detailContent = "项目：<ul>";
            if (row.Tasks.length > 0) {
                $(row.Tasks).each(function (index, item) {
                    detailContent = detailContent + "<li>" + item.TaskName + "</li>";
                });
            }
            detailContent = detailContent + "</ul>";
            $('#ddv-' + index).panel({
                border: false,
                cache: false,
                content: detailContent,
                onLoad: function () {
                    $('#dg').datagrid('fixDetailRowHeight', index);
                }
            });
            $('#dg').datagrid('fixDetailRowHeight', index);
        }
    });
}
);

function newRole() {
    var url = $("#addUrl").val();
    var dlg = $("#opsDialog");
    dlg.dialog({
        width: 500,
        height: 400,
        closed: true,
        cache: false,
        href: $("#addUrl").val(),
        modal: true,
        buttons: [{ text: "保存", iconCls: 'icon-add', handler: function () { } },
        { text: "取消", iconCls: 'icon-cancel', handler: function () { $("#opsDialog").dialog("close"); $("#opsDialog").dialog("destroy"); } }],
        onLoad: function () {
            $("#roleName").validatebox({
                required: true,
                missingMessage: "请输入角色名"
            });
        },
        onDestroy: function () {
            $("#dg").datagrid(“reload”);
        }
    });

    dlg.dialog("open");
}