public PagedDataViewer(ITradeService tradeService, ISchedulerProvider schedulerProvider)
{
//build observable predicate from search text
var filter = this.WhenValueChanged(t => t.SearchText)
.Throttle(TimeSpan.FromMilliseconds(250))
.Select(BuildFilter);
//build observable sort comparer
var sort = SortParameters.WhenValueChanged(t => t.SelectedItem)
.Select(prop => prop.Comparer)
.ObserveOn(schedulerProvider.Background);
//build observable comparer
var currentPageChanged = PageParameters.WhenValueChanged(p => p.CurrentPage);
var pageSizeChanged = PageParameters.WhenValueChanged(p => p.PageSize);
var pager = currentPageChanged.CombineLatest(pageSizeChanged, (page, size) => new PageRequest(page, size))
.StartWith(new PageRequest(1, 25))
.DistinctUntilChanged()
.Sample(TimeSpan.FromMilliseconds(100));
// filter, sort, page and bind to observable collection
_cleanUp = tradeService.All.Connect()
.Filter(filter) // apply user filter
.Transform(trade => new TradeProxy(trade), new ParallelisationOptions(ParallelType.Ordered, 5))
.Sort(sort, SortOptimisations.ComparesImmutableValuesOnly)
.Page(pager)
.ObserveOn(schedulerProvider.MainThread)
.Do(changes => PageParameters.Update(changes.Response))
.Bind(out _data) // update observable collection bindings
.DisposeMany() // dispose when no longer required
.Subscribe();
}
public PagedDataViewer(ITradeService tradeService, ISchedulerProvider schedulerProvider)
{
//watch for filter changes and change filter
var filterController = new FilterController <Trade>(trade => true);
var filterApplier = this.WhenValueChanged(t => t.SearchText)
.Throttle(TimeSpan.FromMilliseconds(250))
.Select(BuildFilter)
.Subscribe(filterController.Change);
//watch for changes to sort and apply when necessary
var sortContoller = new SortController <TradeProxy>(SortExpressionComparer <TradeProxy> .Ascending(proxy => proxy.Id));
var sortChange = SortParameters.WhenValueChanged(t => t.SelectedItem).Select(prop => prop.Comparer)
.ObserveOn(schedulerProvider.TaskPool)
.Subscribe(sortContoller.Change);
//watch for page changes and change filter
var pageController = new PageController();
var currentPageChanged = PageParameters.WhenValueChanged(p => p.CurrentPage);
var pageSizeChanged = PageParameters.WhenValueChanged(p => p.PageSize);
var pageChanger = currentPageChanged.CombineLatest(pageSizeChanged, (page, size) => new PageRequest(page, size))
.DistinctUntilChanged()
.Sample(TimeSpan.FromMilliseconds(100))
.Subscribe(pageController.Change);
// filter, sort, page and bind to loaded data
var loader = tradeService.All.Connect()
.Filter(filterController) // apply user filter
.Transform(trade => new TradeProxy(trade), new ParallelisationOptions(ParallelType.Ordered, 5))
.Sort(sortContoller, SortOptimisations.ComparesImmutableValuesOnly)
.Page(pageController)
.ObserveOn(schedulerProvider.MainThread)
.Do(changes => _pageParameters.Update(changes.Response))
.Bind(out _data) // update observable collection bindings
.DisposeMany() //since TradeProxy is disposable dispose when no longer required
.Subscribe();
_cleanUp = new CompositeDisposable(loader, filterController, filterApplier, sortChange, sortContoller, pageChanger, pageController);
}