public HomeViewModel()
{
ComicEngine = AppEngine.GetRequiredService <ComicEngine>();
SearchEngine = AppEngine.GetRequiredService <SearchEngine>();
ProposalEngine = AppEngine.GetRequiredService <ProposalEngine>();
SearchCommand = new AsyncRelayCommand(SearchAsync);
GoSourceCommand = new RelayCommand(GoSource);
SetAndSearchCommand = new AsyncRelayCommand <string>(SetAndSearchAsync);
ResetCommand = new RelayCommand(Reset);
SetCurrentCommand = new RelayCommand <ComicSnapshotInfo <TSourceInfo> >(SetCurrent);
CopyCommand = new RelayCommand <string>(Copy);
scope = AppEngine.CreateScope();
observableCollectionFactory = AppEngine.GetRequiredService <IObservableCollectionFactory>();
SearchProviders = observableCollectionFactory.Create <ISearchProvider>();
foreach (var item in SearchEngine)
{
var sp = (ISearchProvider)scope.ServiceProvider.GetRequiredService(item);
SearchProviders.Add(sp);
}
CurrentSearchProvider = SearchProviders.FirstOrDefault();
Snapshots = observableCollectionFactory.Create <ComicSnapshotInfo <TSourceInfo> >();
ProposalSnapshots = observableCollectionFactory.Create <ComicSnapshotInfo <TSourceInfo> >();
EngineIcons = observableCollectionFactory.Create <EngineInfo <TImage> >();
}
// Raised when a search provider is added or removed
private void SearchProviders_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
{
if (e.NewItems != null)
{
object input = null;
// Get existing input so new providers' inputs can be synced
if (SearchProviders.Count > e.NewItems.Count)
{
ISearchProvider preExistingProvider = SearchProviders.FirstOrDefault(p => !e.NewItems.Contains(p));
if (preExistingProvider != null)
{
input = preExistingProvider.Input;
}
}
foreach (ISearchProvider provider in e.NewItems)
{
// Listen for property changes on any new search providers
provider.PropertyChanged += SearchProvider_PropertyChanged;
// Initialize input
provider.Input = input;
}
}
if (e.OldItems != null)
{
// Unhook from property changes on any removed search providers
foreach (ISearchProvider provider in e.OldItems)
{
provider.PropertyChanged -= SearchProvider_PropertyChanged;
}
}
raiseCanExecuteChanged();
}
