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.
OneTime bindings were failing in BindingTest because the initial binding
error was being counted as the single value to transfer. Don't do this
with OneTime bindings - only transfer valid values.
This is needed so that things like the following can be done:
<TreeView>
<TreeView.Styles>
<Style Selector="TreeViewItem">
<Setter Property="IsExpanded" Value="{Binding IsExpanded}"/>
</Style>
</TreeView.Styles>
<TreeView>
(At the moment we have TreeDataTemplate.IsExpanded but this isn't good
enough: it only supports setting IsExpanded on creation of the item with
no binding.)
With this commit, setters can now contain bindings, but they aren't yet
applied correctly. As part of this commit, classes related to binding
have been moved to the Perspex.Data namespace.
Described by XamlBindingTest.Should_Not_Write_To_Old_DataContext.
Problem still remains with ListBox.SelectedItems however, that's going
to require something more.
Steven Kirk
Jeremy Koritzinsky
Steven Kirk
Nikita Tsukanov