C# ReplaySubject.DistinctUntilChanged方法代码示例

        public InlineViewer([NotNull] InlineViewerArgs args,
            [NotNull] IClipboardHandler clipboardHandler,
            [NotNull] ISchedulerProvider schedulerProvider, 
            [NotNull] ISelectionMonitor selectionMonitor,
            [NotNull] ILogger logger, 
            [NotNull] IThemeProvider themeProvider)
        {
            if (args == null) throw new ArgumentNullException(nameof(args));
            if (clipboardHandler == null) throw new ArgumentNullException(nameof(clipboardHandler));
            if (schedulerProvider == null) throw new ArgumentNullException(nameof(schedulerProvider));
            if (selectionMonitor == null) throw new ArgumentNullException(nameof(selectionMonitor));
            if (themeProvider == null) throw new ArgumentNullException(nameof(themeProvider));
            SelectionMonitor = selectionMonitor;
            CopyToClipboardCommand = new Command(() => clipboardHandler.WriteToClipboard(selectionMonitor.GetSelectedText()));

            _isSettingScrollPosition = false;

            var lineProvider = args.LineProvider;
            var selectedChanged = args.SelectedChanged;
            var pageSize = this.WhenValueChanged(vm=>vm.PageSize);

            //if use selection is null, tail the file
            var scrollSelected = selectedChanged
                    .CombineLatest(lineProvider, pageSize, (proxy, lp, pge) => proxy == null ? new ScrollRequest(pge,0) : new ScrollRequest(pge, proxy.Start))
                    .DistinctUntilChanged();

            var horizonalScrollArgs = new ReplaySubject<TextScrollInfo>(1);
            HorizonalScrollChanged = hargs =>
            {
                horizonalScrollArgs.OnNext(hargs);
            };

            var scrollUser = _userScrollRequested
                .Where(x => !_isSettingScrollPosition)
                .Select(request => new ScrollRequest(ScrollReason.User, request.PageSize, request.FirstIndex));

            var scroller = scrollSelected.Merge(scrollUser)
                .ObserveOn(schedulerProvider.Background)
                .DistinctUntilChanged();

            var lineScroller = new LineScroller(lineProvider, scroller);
            Count = lineProvider.Select(lp=>lp.Count).ForBinding();

            MaximumChars = lineScroller.MaximumLines()
                            .ObserveOn(schedulerProvider.MainThread)
                            .ForBinding();

            var proxyFactory = new LineProxyFactory(new TextFormatter(args.SearchMetadataCollection), new LineMatches(args.SearchMetadataCollection), horizonalScrollArgs.DistinctUntilChanged(), themeProvider);

            //load lines into observable collection
            var loader = lineScroller.Lines.Connect()
                .Transform(proxyFactory.Create,new ParallelisationOptions(ParallelType.Ordered,3))
                .Sort(SortExpressionComparer<LineProxy>.Ascending(proxy => proxy))
                .ObserveOn(schedulerProvider.MainThread)
                .Bind(out _data)
                .DisposeMany()
                .LogErrors(logger)
                .Subscribe();

            // track first visible index [required to set scroll extent]
            var firstIndexMonitor = lineScroller.Lines.Connect()
                .Buffer(TimeSpan.FromMilliseconds(250)).FlattenBufferResult()
                .ToCollection()
                .Select(lines => lines.Count == 0 ? 0 : lines.Select(l => l.Index).Max() - lines.Count + 1)
                .ObserveOn(schedulerProvider.MainThread)
                .Subscribe(first =>
                {
                    try
                    {
                        _isSettingScrollPosition = true;
                        FirstIndex = first;
                    }
                    finally
                    {
                        _isSettingScrollPosition = false;
                    }
                });

            _cleanUp = new CompositeDisposable(lineScroller,
                        loader,
                        Count,
                        firstIndexMonitor,
                        SelectionMonitor,
                         MaximumChars,
                        horizonalScrollArgs.SetAsComplete(),
                        _userScrollRequested.SetAsComplete());
        }

        public TailViewModel([NotNull] ILogger logger,
            [NotNull] ISchedulerProvider schedulerProvider,
            [NotNull] IFileWatcher fileWatcher,
            [NotNull] ISelectionMonitor selectionMonitor, 
            [NotNull] IClipboardHandler clipboardHandler, 
            [NotNull] ISearchInfoCollection searchInfoCollection, 
            [NotNull] IInlineViewerFactory inlineViewerFactory,
            [NotNull] GeneralOptionBindings generalOptionBindings,
            [NotNull] ICombinedSearchMetadataCollection combinedSearchMetadataCollection,
            [NotNull] IStateBucketService stateBucketService,
            [NotNull] ITailViewStateRestorer restorer,
            [NotNull] SearchHints searchHints,
            [NotNull] ITailViewStateControllerFactory tailViewStateControllerFactory,
            [NotNull] IThemeProvider themeProvider,
            [NotNull] SearchCollection searchCollection, 
            [NotNull] ITextFormatter textFormatter,
            [NotNull] ILineMatches lineMatches,
            [NotNull] IObjectProvider objectProvider,
            [NotNull] IDialogCoordinator dialogCoordinator)
        {
            if (logger == null) throw new ArgumentNullException(nameof(logger));
            if (schedulerProvider == null) throw new ArgumentNullException(nameof(schedulerProvider));
            if (fileWatcher == null) throw new ArgumentNullException(nameof(fileWatcher));
            if (selectionMonitor == null) throw new ArgumentNullException(nameof(selectionMonitor));
            if (clipboardHandler == null) throw new ArgumentNullException(nameof(clipboardHandler));
            if (searchInfoCollection == null) throw new ArgumentNullException(nameof(searchInfoCollection));
            if (inlineViewerFactory == null) throw new ArgumentNullException(nameof(inlineViewerFactory));
            if (stateBucketService == null) throw new ArgumentNullException(nameof(stateBucketService));
            if (searchHints == null) throw new ArgumentNullException(nameof(searchHints));
            if (themeProvider == null) throw new ArgumentNullException(nameof(themeProvider));
            if (searchCollection == null) throw new ArgumentNullException(nameof(searchCollection));
            if (textFormatter == null) throw new ArgumentNullException(nameof(textFormatter));
            if (lineMatches == null) throw new ArgumentNullException(nameof(lineMatches));
            if (objectProvider == null) throw new ArgumentNullException(nameof(objectProvider));
            if (dialogCoordinator == null) throw new ArgumentNullException(nameof(dialogCoordinator));
            if (combinedSearchMetadataCollection == null) throw new ArgumentNullException(nameof(combinedSearchMetadataCollection));

            Name = fileWatcher.FullName;
            SelectionMonitor = selectionMonitor;
            GeneralOptionBindings = generalOptionBindings;
            SearchHints = searchHints;

            CopyToClipboardCommand = new Command(() => clipboardHandler.WriteToClipboard(selectionMonitor.GetSelectedText()));
            OpenFileCommand = new Command(() => Process.Start(fileWatcher.FullName));
            OpenFolderCommand = new Command(() => Process.Start(fileWatcher.Folder));
            CopyPathToClipboardCommand = new Command(() => clipboardHandler.WriteToClipboard(fileWatcher.FullName));
            UnClearCommand = new Command(fileWatcher.Reset);
            ClearCommand = new Command(fileWatcher.Clear);
            KeyAutoTail = new Command(() => { AutoTail = true; });
            OpenSearchOptionsCommand = new Command(async () =>
            {
                await Task.Run(() =>
                {
                    var content = objectProvider.Get<SearchOptionsViewModel>(new Argument<ICombinedSearchMetadataCollection>(combinedSearchMetadataCollection));
                    dialogCoordinator.Show(this, content, x => content.Dispose());
                });
            });

            SearchCollection = searchCollection;
            SearchMetadataCollection = combinedSearchMetadataCollection.Local;

            var horizonalScrollArgs = new ReplaySubject<TextScrollInfo>(1);
            HorizonalScrollChanged = args => horizonalScrollArgs.OnNext(args);

            _tailViewStateControllerFactory = tailViewStateControllerFactory;

            //this deals with state when loading the system at start up and at shut-down
            _persister = new TailViewPersister(this, restorer);

            FileStatus = fileWatcher.Status.ForBinding();

            //command to add the current search to the tail collection
            var searchInvoker = SearchHints.SearchRequested.Subscribe(request => searchInfoCollection.Add(request.Text, request.UseRegEx));

            //An observable which acts as a scroll command
            var autoChanged = this.WhenValueChanged(vm => vm.AutoTail);
            var scroller = _userScrollRequested.CombineLatest(autoChanged, (user, auto) =>
            {
                var mode = AutoTail ? ScrollReason.Tail : ScrollReason.User;
                return new ScrollRequest(mode, user.PageSize, user.FirstIndex);
            })
            .Do(x => logger.Info("Scrolling to {0}/{1}", x.FirstIndex, x.PageSize))
            .DistinctUntilChanged();

            //User feedback to show file size
            FileSizeText = fileWatcher.Latest.Select(fn=>fn.Size)
                .Select(size => size.FormatWithAbbreviation())
                .DistinctUntilChanged()
                .ForBinding();

            //tailer is the main object used to tail, scroll and filter in a file
            var selectedProvider = SearchCollection.Latest.ObserveOn(schedulerProvider.Background);

            var lineScroller = new LineScroller(selectedProvider, scroller);

            MaximumChars = lineScroller.MaximumLines()
                            .ObserveOn(schedulerProvider.MainThread)
                            .ForBinding();

            var lineProxyFactory = new LineProxyFactory(textFormatter, lineMatches, horizonalScrollArgs.DistinctUntilChanged(), themeProvider);
//.........这里部分代码省略.........