public IObservable <Action> LoadPrevMessages(
Target target,
SourceList <ItemModel> items)
{
switch (target)
{
case Chat chat:
return(LoadPrevMessages(chat, items)
.Aggregate(new List <Message>(), (list, m) =>
{
list.Add(m);
return list;
})
.Select(messages => new Action(() =>
{
var models = messages
.Select(_messageModelFactory.CreateMessage)
.Reverse()
.ToList();
items.InsertRange(models, 0);
})));
}
return(Observable.Empty <Action>());
}
private IDisposable InitMessageLoading(
Target target,
IMessageManager messageManager,
IAvatarManager avatarManager)
{
var messageLoading = messageManager.LoadPrevMessages(target)
.Select(models => new {
Action = new Action(() =>
{
_items.InsertRange(models, 0);
}),
Models = models
});
var avatarLoading = messageLoading
.SelectMany(item =>
{
var action = item.Action;
var models = item.Models;
var messageLoadAction = Observable.Return(action);
var avatarPreloadAction = avatarManager.PreloadAvatars(models)
.Select((avatar, i) => new Action(() =>
{
var messageModel = models[i];
messageModel.Avatar = avatar;
}));
var avatarLoadAction = avatarManager.LoadAvatars(models)
.Select((avatar, i) => new Action(() =>
{
var messageModel = models[i];
messageModel.Avatar = avatar;
}));
return(messageLoadAction
.Concat(avatarPreloadAction)
.Concat(avatarLoadAction));
});
return(SubscribeToActions(avatarLoading));
}
public void InsertRange()
{
var people = _generator.Take(100).ToList();
_source.AddRange(people);
var morePeople = _generator.Take(100).ToList();
_source.InsertRange(morePeople, 50);
Assert.AreEqual(200, _collection.Count, "Should be 200 items in the collection");
CollectionAssert.AreEquivalent(_collection.Skip(50).Take(100), morePeople, "Collections should be equivalent");
}
private IDisposable BindChatLoading(
IObservable <MessageLoadRequestedArgs> loadRequests,
Chat chat,
IMessageLoader messageLoader,
IMessageModelFactory messageModelFactory)
{
return(loadRequests
.ObserveOn(TaskPoolScheduler.Default)
.SelectMany(signal =>
{
var messages = signal.Direction == LoadDirection.Next
? LoadNextMessages(chat, messageLoader)
: LoadPrevMessages(chat, messageLoader);
return messages.Aggregate(new List <Message>(), (list, m) =>
{
list.Add(m);
return list;
})
.Select(list => new
{
Direction = signal.Direction,
Messages = list
});
})
.Subscribe(data =>
{
var direction = data.Direction;
var models = data.Messages
.Select(messageModelFactory.CreateMessage)
.Reverse()
.ToList();
switch (direction)
{
case LoadDirection.Prev:
_items.InsertRange(models, 0);
break;
case LoadDirection.Next:
_items.AddRange(models);
break;
}
}));
}
