During initial layout, `TemplatedParent` is read tens of thousands of times. This being a styled property that used `inherits: true` meant that it was showing up in profiling as taking up a significant amount of time.
Make `TemplatedParent` a direct property so that reading it is a simple property access. This doesn't actually complicate the code much at all as once set the property value doesn't change, so `inherited: true` semantics are not that important.
Previous its color was immutable but because it inherited from Brush, its Opacity was mutable. This wasn't good, as it meant that e.g. Brushes.Red could be changed. Make it properly immutable by using the IBrush interface everywhere and not inheriting from Brush.
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.
...during ApplyTemplate. This was so that ItemsControls could their find
ItemsPresenters nested in other templated controls. Instead use
IItemsPresenterHost to make the presenter register itself with its
TemplatedParent.
Usually controls are only registered with their name scope when they get
added to a rooted visual tree, but this causes problems for tests, and
would mean the templated control wouldn't work if the client called
ApplyTemplate themselves before the control is added to the visual tree.
Work around this by explicitly registering template controls with the
name scope when the template is applied.
To allow this, we need to allow controls to be registered with a name
scope multiple times.
Some tests still failing as controls are only registered with name scope
when attached to a rooted visual tree. Need to work around this by
explicitly registering controls when applying template.
Wiesław Šoltés
Benedikt Stebner
robloo
Steven Kirk
Max Katz
Dariusz Komosinski
Nikita Tsukanov
Steven Kirk
Benedikt Schroeder
José Pedro
Steven Kirk