Instead of using `Observable.ObserveOn` in bindings, interface with `Dispatcher.UIThread` to schedule binding notifications on the UI thread. This saves a significant amount of memory.
Previously it wasn't clear which constructor on `InstancedBinding` must be called for a particular binding mode. Refactored the constructors:
- We now have a single public ctor which takes an `ISubject`, as a subject can be used for all binding modes.
- Instanced bindings with other sources such as single values and `IObservables` are now constructed via static methods which only allow the correct sources for that binding mode
To do this needed to change behavior a little in that now binding errors update the target. Previously in the case of a binding error at the first node in the binding chain, we were converting the `BindingNotification` to `UnsetValue` which had the effect of updating the target value. Now we're passing the `BindingNotification` back, we need to make sure this happens. I believe this is the right thing to do as the behavior should be the same no matter where in the binding chain the error occurs. Data validation errors continue to not update the target.
1. Fixed some tests to expect `BindingNotification`s to be returned on a broken binding chain.
2. Changed logging of `BindingNotification`s - log at `Warning` level (instead of `Error`) except when the binding chain is broken at the root, in which case log at `Information` level. Do this to prevent flooding the output window when initializing.
Previously we ensured that `AvaloniaObject.SetValue` was run on the main
thread. This makes sure that `GetValue`, `IsSet` and `ClearValue` are
also run on the main thread. Unit testing this turned out to be more
complicated than expected, because `Dispatcher` keeps a hold of a
reference to the first `IPlatformThreadingInterface` it sees, so made
`UnitTestApplication` able to notify `Dispatcher` that it should update
its services.
Steven Kirk
José Pedro
Jeremy Koritzinsky
Nikita Tsukanov
Wiesław Šoltés
Wiesław Šoltés
donandren