光滑的網格確保數據沒有被調用

Question

我正在使用以下javascript的光滑網格。問題是控件永遠不會確保Data（）。有任何想法嗎？

grid.onViewportChanged.subscribe(function (e, args) { 
    alert('1'); 
    var vp = grid.getViewport(); 
    alert('2'); 
    loader.ensureData(vp.top, vp.bottom); 
    alert('3'); 
}); 

function ensureData(from, to) 
{   
    alert('55'); 
    var maxdata = Math.min(999, data.length); 
    if (from < 0) 
    from = 0; 
    if (to > maxdata) 
     to = maxdata; 

    var fromPage = Math.floor(from/PAGESIZE); 
    var toPage = Math.floor(to/PAGESIZE); // look-ahead 

    while (fromPage <= toPage) { 
     if (data[fromPage * PAGESIZE] == undefined) { 
      data[fromPage * PAGESIZE] = null; // null indicates a 'requested but not available yet' 

      var order = { "query": searchstr, "offset": (fromPage * PAGESIZE), "count": (((toPage - fromPage) * PAGESIZE) + PAGESIZE), "sort": sortcol, "order": ((sortdir > 0) ? "asc" : "desc") }; 
      req = $.ajax({ 
       type: "POST", 
       contentType: "application/json; charset=utf-8", 
       dataType: "json", 
       data: JSON.stringify(order), 

       url: "OrderService.svc/GetOrderList", 

       success: onSuccess, 
       error: function (jqXHR, textStatus, errorThrown) { 
        if (textStatus != 'abort') 
         onError(fromPage, toPage); 
       } 
      }); 
      onDataLoading.notify(); 
     } 
     fromPage++; 
    } 
} 

警報1所示然後被示 警報2然後 警報（錯誤裝載的數據）被示出&最後 警報3示出....

Answer 1

它不應該觸發頁面上加載。顧名思義，它會在視口發生變化時觸發，即當用戶滾動並且視口中的頂部和底部可見行發生變化時。