/// <summary>
/// Needs to be called as soon as it is desired to display the first 'Page' of data.
/// </summary>
/// <remarks>All further pages are loaded by the control on demand!</remarks>
/// <param name="ADelegateGetDataPagedResultFunction">Delegate function that gets called
/// when a Page of data needs to be retrieved.
/// </param>
/// <param name="AAddEmptyRows">Whether empty Rows for the data that *hasn't* been loaded
/// in the first 'Data Page' should be added, or not. Set this to false if you are planning to call
/// .AutoSizeCells() on the Grid and there is a possibility that there could be more than a couple of hundred
/// records in total. The reason is that calling .AutoSizeCells() can take a considerable amount of time if there
/// are many Cells to autosize (ie. the combination of Columns and Rows is high). If set to false, a separate
/// call to the Method <see cref="AddEmptyRows" /> needs to be made by the caller after .AutoSizeCells()
/// has been called on the Grid to add the empty rows at that point in time! (This results in the AutoSize only
/// taking the first Data Page's rows into consideration for the auto-sizing, but that is why it will not be slow!)</param>
/// <returns>A DataTable holding the records that fitted into the first 'Data Page'.</returns>
public DataTable LoadFirstDataPage(TDelegateGetDataPagedResult ADelegateGetDataPagedResultFunction, bool AAddEmptyRows = true)
{
DataTable ReturnValue;
TDataPageLoadEventArgs CustomEventArgs;
// TLogging.Log("Enter LoadFirstDataPage...");
// TLogging.Log("LoadFirstDataPage: HScrollBarVisible: " + HScrollBarVisible.ToString());
DeterminePageSize();
FGetDataPagedResult = ADelegateGetDataPagedResultFunction;
FLastHeight = this.Height;
if (FGetDataPagedResult != null)
{
// Fire OnDataPageLoading event.
CustomEventArgs = new TDataPageLoadEventArgs();
CustomEventArgs.DataPage = 0;
this.OnDataPageLoading(CustomEventArgs);
// Fetch the first page of data
if (FPageSize < FMinimumPageSize)
{
FPageSize = FMinimumPageSize;
}
FPagedDataTable = FGetDataPagedResult(0, FPageSize, out FTotalRecords, out FTotalPages);
ReturnValue = FPagedDataTable;
DataTransferDone(AAddEmptyRows);
// Fire OnDataPageLoaded event.
CustomEventArgs = new TDataPageLoadEventArgs();
CustomEventArgs.DataPage = 0;
this.OnDataPageLoaded(CustomEventArgs);
}
else
{
throw new EDataGridPagedDelegateFunctionNotSpecifiedException(
"The " + this.GetType().FullName + " control is not properly initialised yet. " +
"The ADelegateGetDataPagedResultFunction parameter of the InitialiseGrid method needs to be set to the delegate function that returns a page of data");
}
FGridInitialised = true;
// TLogging.Log("LoadFirstDataPage is finished.");
return(ReturnValue);
}
/// <summary>
/// Needs to be called as soon as it is desired to display the first 'Page' of data.
/// </summary>
/// <remarks>All further pages are loaded by the control on demand!</remarks>
/// <param name="ADelegateGetDataPagedResultFunction">Delegate function that gets called
/// when a Page of data needs to be retrieved.
/// </param>
/// <param name="AAddEmptyRows">Whether empty Rows for the data that *hasn't* been loaded
/// in the first 'Data Page' should be added, or not. Set this to false if you are planning to call
/// .AutoSizeCells() on the Grid and there is a possibility that there could be more than a couple of hundred
/// records in total. The reason is that calling .AutoSizeCells() can take a considerable amount of time if there
/// are many Cells to autosize (ie. the combination of Columns and Rows is high). If set to false, a separate
/// call to the Method <see cref="AddEmptyRows" /> needs to be made by the caller after .AutoSizeCells()
/// has been called on the Grid to add the empty rows at that point in time! (This results in the AutoSize only
/// taking the first Data Page's rows into consideration for the auto-sizing, but that is why it will not be slow!)</param>
/// <returns>A DataTable holding the records that fitted into the first 'Data Page'.</returns>
public DataTable LoadFirstDataPage(TDelegateGetDataPagedResult ADelegateGetDataPagedResultFunction, bool AAddEmptyRows = true)
{
DataTable ReturnValue;
TDataPageLoadEventArgs CustomEventArgs;
// TLogging.Log("Enter LoadFirstDataPage...");
// TLogging.Log("LoadFirstDataPage: HScrollBarVisible: " + HScrollBarVisible.ToString());
DeterminePageSize();
FGetDataPagedResult = ADelegateGetDataPagedResultFunction;
FLastHeight = this.Height;
if (FGetDataPagedResult != null)
{
// Fire OnDataPageLoading event.
CustomEventArgs = new TDataPageLoadEventArgs();
CustomEventArgs.DataPage = 0;
this.OnDataPageLoading(CustomEventArgs);
// Fetch the first page of data
if (FPageSize < FMinimumPageSize)
{
FPageSize = FMinimumPageSize;
}
FPagedDataTable = FGetDataPagedResult(0, FPageSize, out FTotalRecords, out FTotalPages);
ReturnValue = FPagedDataTable;
DataTransferDone(AAddEmptyRows);
// Fire OnDataPageLoaded event.
CustomEventArgs = new TDataPageLoadEventArgs();
CustomEventArgs.DataPage = 0;
this.OnDataPageLoaded(CustomEventArgs);
}
else
{
throw new EDataGridPagedDelegateFunctionNotSpecifiedException(
"The " + this.GetType().FullName + " control is not properly initialised yet. " +
"The ADelegateGetDataPagedResultFunction parameter of the InitialiseGrid method needs to be set to the delegate function that returns a page of data");
}
FGridInitialised = true;
// TLogging.Log("LoadFirstDataPage is finished.");
return ReturnValue;
}
