public static void LazyLoad <T>(VirtualGridData <T> d) where T : new()
{
Task.Factory.StartNew(() => {
using (BLL.GeneralBll bll = new BLL.GeneralBll())
{
lock (obj)
{
int endIndex = Math.Min(d.LoadedCount + d.PerLoadSize, d.Data.Count);
var lazyData = bll.Select <T>(d.Grid.SortDescriptors.Expression, d.Grid.FilterDescriptors.Expression, d.LoadedCount + 1, endIndex);//bll.Read().OrderByDescending(x => x.ID).Skip(this.loadedRowCount).Take(endIndex - this.loadedRowCount).ToList();
for (int i = d.LoadedCount; i < endIndex; i++)
{
d.Data[i] = lazyData[i - d.LoadedCount];
}
d.LoadedCount = endIndex;
}
}
}).ContinueWith(t => {
syncContext.Post((state) => {
//dynamic da = state;
//var grid = da.Grid as RadVirtualGrid;
var grid = d.Grid;
if (grid.IsDisposed)
{
return;
}
int waitingRow = grid.RowCount - 1;
grid.RowCount = Math.Min(d.LoadedCount + 1, d.Data.Count);
grid.MasterViewInfo.StopRowWaiting(waitingRow);
}, d);
});
}
private static SynchronizationContext syncContext = SynchronizationContext.Current; //线程中更新UI模型传播上下文
/// <summary>
/// 设置virtualgrid 数据 并设置 CellValueNeeded
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="d"></param>
/// <param name="syncContext"></param>
public static void InitalLoad <T>(VirtualGridData <T> d) where T : new()
{
var grid = d.Grid;
grid.RowCount = 0;
grid.ColumnCount = ModelHelper.GetColumnDisplayNames(typeof(T)).Count();
////设置Column宽度
//grid.TableElement.ColumnsViewState.SetItemSize(0,30);
//grid.ColumnWidthChanging += (s, e) => {
// //ID列为命令按钮，固定大小，不允许resize
// int idIndex = Array.IndexOf(ModelHelper.GetColumnNames(typeof(T)), "ID");
// if (e.ColumnIndex==idIndex)
// {
// e.Cancel = true;
// }
//};
//grid.CreateCellElement += (s, e) => {
// //ID列约定为命令按钮
// int idIndex = Array.IndexOf(ModelHelper.GetColumnNames(typeof(T)), "ID");
// if (e.RowIndex>=0 && e.ColumnIndex == idIndex)
// {
// e.CellElement = new Helpers.VirtualGridEditCommandCellElement();
// }
//};
//grid.CellFormatting += (s, e) => {
// //ID列约定为命令按钮
// int idIndex = Array.IndexOf(ModelHelper.GetColumnNames(typeof(T)), "ID");
// if (e.CellElement.RowIndex == -3 && e.CellElement.ColumnIndex == idIndex)
// {
// e.CellElement.Visibility = Telerik.WinControls.ElementVisibility.Hidden;
// }
// if (e.CellElement.RowIndex == -1 && e.CellElement.ColumnIndex == idIndex)
// {
// e.CellElement.Visibility= Telerik.WinControls.ElementVisibility.Hidden;
// }
//};
grid.CellValueNeeded += (s, e) => {
if (e.ColumnIndex < 0 || d.Data == null) //|| data == null
{
return;
}
if (e.RowIndex == RadVirtualGrid.HeaderRowIndex)
{
e.Value = Helpers.ModelHelper.GetColumnDisplayNames(typeof(T))[e.ColumnIndex];
}
if (e.RowIndex < 0)
{
e.FieldName = ModelHelper.GetColumnNames(typeof(T))[e.ColumnIndex];
}
if (e.RowIndex == e.ViewInfo.RowCount - 1 && e.ViewInfo.RowCount < d.Data.Count)
{
e.Value = null;
e.ViewInfo.StartRowWaiting(e.RowIndex);
LazyLoad <T>(d);
//if (!this.lazyLoader.IsBusy)
//{
// this.lazyLoader.RunWorkerAsync();
//}
}
else if (e.RowIndex >= 0)
{
e.Value = ModelHelper.GetValueByPropertyName <T>(d.Data[e.RowIndex], ModelHelper.GetColumnNames(typeof(T))[e.ColumnIndex]);
}
};
if (!grid.MasterViewInfo.IsWaiting)
{
grid.MasterViewInfo.IsWaiting = true;
}
Task.Factory.StartNew(() => {
using (BLL.GeneralBll bll = new BLL.GeneralBll())
{
lock (obj)
{
var count = bll.CountTable <T>(grid.FilterDescriptors.Expression);
d.Data = new List <T>(count);
for (int i = 0; i < count; i++)
{
d.Data.Add(new T());
}
var initData = bll.Select <T>(grid.SortDescriptors.Expression, grid.FilterDescriptors.Expression, 1, d.PerLoadSize);
d.LoadedCount = initData == null? 0: initData.Count();
if (initData != null)
{
for (int i = 0; i < initData.Count; i++)
{
d.Data[i] = initData[i];
}
}
}
}
}).ContinueWith(t => {
syncContext.Post((state) => {
//dynamic d = state;
//var grid = da.Grid as RadVirtualGrid;
if (grid.IsDisposed)
{
return;
}
if (!t.IsFaulted)
{
grid.RowCount = Math.Min(d.LoadedCount + 1, d.Data.Count);
}
if (grid.MasterViewInfo.IsWaiting)
{
grid.MasterViewInfo.IsWaiting = false;
}
}, d);
});
}