public async override void Execute(object parameter)
{
base.Execute(parameter);
LoadMoreDataContext context = (LoadMoreDataContext)parameter;
LoadOnDemandCommand.ViewModel viewModel = (LoadOnDemandCommand.ViewModel)context.DataContext;
this.lodCounter++;
if (this.lodCounter % 3 == 0)
{
// If we do not need to get new data asynchronously, we can add the new items right away.
viewModel.AddItems(15);
}
else
{
// If we need to get new data asynchronously, we must manually update the loading status.
this.Owner.ChangeDataLoadingStatus(BatchLoadingStatus.ItemsRequested);
// Mimic getting data from server asynchronously.
await Task.Delay(2000);
viewModel.AddItems(15);
this.Owner.ChangeDataLoadingStatus(BatchLoadingStatus.ItemsLoaded);
}
}
public override bool CanExecute(object parameter)
{
LoadMoreDataContext context = (LoadMoreDataContext)parameter;
LoadOnDemandCommand.ViewModel viewModel = (LoadOnDemandCommand.ViewModel)context.DataContext;
bool canExecute = viewModel.Items.Count < 100;
return(canExecute);
}