public virtual void BeginStepTask(string name, int totalWork, int stepSize)
{
progressTracker.BeginStepTask(name, totalWork, stepSize);
OnProgressChanged();
}
void IProgressMonitor.BeginStepTask(string name, int totalWork, int stepSize)
{
tracker.BeginStepTask(name, totalWork, stepSize);
SetMessage(tracker.CurrentTask);
}