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.
If a TextBox is e.g. bound to an int and the user types "02" then the
TextBox text should be "02" - not the value that comes back from the
binding which will be "2".
Doing a `Publish().Refcount()` caches the latest value so it can be sent
to subsequent subscribers, and this causes a leak. Convert the value
to/from `WeakReference` for that part.
This speeds up the common path of no data validation: this way we don't
need to get the metadata unless a binding notification is received. This
means that if a binding with data validation is assigned to a property
that isn't interested then UpdateDataValidation will be called, but the
control should just ignore it.
This reverts commit 57e646583f.
For TextBox there can be 2 bindings to Text: one which is the binding to the
view model which should have data validation enabled, and another binding to
the TextPresenter in the template which should not have data validation
enabled, or it will override the view model data validation. For this we need
to be able to distinguish between the two and so bindings with data validation
enabled need to always send BindingNotifications.
Conflicts:
src/Avalonia.Base/AvaloniaObject.cs
tests/Avalonia.Markup.Xaml.UnitTests/Data/BindingTests_Validation.cs
We're going to say that for the moment only direct properties handle
data validation. This gets around a few thorny issues with data
validation on styled properties.
Introduced in a refactoring a few commits ago where I saw code that
looked wrong. It wasn't wrong, it's just the mechanism is a little
unintuitive. Added a comment explaining the reasoning.
These are used to extensibly handle special values like `Task` and
`IObservable<>`. Previously this was baked into the expression observer
architecture with a TODO comment saying that it needs to be extensible.
And use it as base class for test data that implements
INotifyDataErrorInfo. Removed IndeiValidatorTests as its been
superceeded by IndeiValidationPluginTests.
Steven Kirk
Steven Kirk