protected virtual void BgWorkerDoWork(object sender, DoWorkEventArgs e)
{
ItemSourceOperation operations = default(ItemSourceOperation);
while (this.queuedOperations.Count > 0 && this.perform)
{
OperationParameters currentParams;
if (!this.queuedOperations.TryDequeue(out currentParams))
{
System.Threading.Thread.Sleep(100);
continue;
}
this.backgroundWorker.ReportProgress(0, currentParams.Operation);
switch (currentParams.Operation)
{
case ItemSourceOperation.Filtering:
this.Filter(currentParams.Descriptors as FilterDescriptorCollection);
break;
case ItemSourceOperation.Sorting:
this.Sort(currentParams.Descriptors as SortDescriptorCollection);
break;
default:
break;
}
operations |= currentParams.Operation;
}
e.Result = new ItemSourceOperationCompletedEventArgs(operations, !this.perform);
}
public void PerformOperation(ItemSourceOperation operation, IList descriptors, bool force = false)
{
switch (operation)
{
case ItemSourceOperation.Filtering:
FilterDescriptorCollection filterDescriptors = descriptors as FilterDescriptorCollection;
if (this.lastFilterExpression == filterDescriptors.Expression && !force)
{
return;
}
this.lastFilterExpression = filterDescriptors.Expression;
break;
case ItemSourceOperation.Sorting:
SortDescriptorCollection sortDescriptors = descriptors as SortDescriptorCollection;
if (this.lastSortExpression == sortDescriptors.Expression && !force)
{
return;
}
this.lastSortExpression = sortDescriptors.Expression;
break;
default:
break;
}
OperationParameters operationParams = new OperationParameters(operation, descriptors);
this.queuedOperations.Enqueue(operationParams);
if (this.backgroundWorker.IsBusy)
{
OperationParameters peek;
bool peeked = this.queuedOperations.TryPeek(out peek);
if (peeked && peek.Operation == operationParams.Operation && peek != operationParams)
{
OperationParameters dequeued;
this.queuedOperations.TryDequeue(out dequeued);
}
else if (peeked && peek.Operation != operationParams.Operation)
{
this.perform = false;
}
}
if (!this.backgroundWorker.IsBusy)
{
this.perform = true;
this.backgroundWorker.RunWorkerAsync();
this.OnOperationStarted(new ItemSourceOperationEventArgs(operationParams.Operation));
}
}
public OperationParameters(ItemSourceOperation operation, IList descriptors)
{
this.Operation = operation;
this.Descriptors = descriptors;
}
public ItemSourceOperationCompletedEventArgs(ItemSourceOperation operation, bool canceled)
: base(operation)
{
this.Canceled = canceled;
}
public ItemSourceOperationEventArgs(ItemSourceOperation operation)
{
this.OperationType = operation;
}
