WinUI 3.0 : WPF features that should be in WinRT XAML

[mdtauk]

I remember since Windows 8 and the introduction of WinRT - many times people saying they couldn't make a control, or couldn't achieve X Y Z - because something they took for granted in WPF didn't exist in the newer WinRT version of XAML.

With WinUI 3.0 and the convergence of WPF and UWP as open source libraries...

What should be added to WinRT XAML that exists in WPF, and why?

[huoyaoyuan]

{x:Bind} equivalent for DataTrigger

I don't know if there is a simple way to convert an enum into themed color, or localized string. Visual states are too heavy for this.

Limited dynamic resource support

Dynamic resource are harmful to performance, but useful for custom theming support. Currently {ThemeResource} only supports system defined themes, and can't be used from code.

[rmarinho]

WinUI Xaml should support XAML 2009 language features

https://docs.microsoft.com/en-us/dotnet/framework/xaml-services/xaml-2009-language-features

it only implements 2006

[bschoepke]

VisualBrush is a good one. You can achieve mostly the same outcome using windows.ui.composition.redirectvisual but it's less convenient than a brush, and there's no way to "Freeze" it.

https://docs.microsoft.com/en-us/dotnet/api/system.windows.media.visualbrush?view=netframework-4.8

[Psykobal]

Support bindings in style setters, it's a very common feature in wpf and there isn't any "easy" workaround.

It has an Uservoice request

[TonyHenrique]

A proper Window object would be awesome in WinRT.

[mfe-]

I just gonna quote myself here.

[...]

• Style Triggers missing
• The ability to use e.g. BasedOn={StaticResource {x:Type TextBlock}} in a Style
• Defined DataTemplates with DataTypes aren't automatically applied like in WPF (only via Key)
• Why is every second Windows.UI.Xaml.Controls control (TextBlock, Border,...) declared as sealed?! Please don't do this in WinUI 3.0 with UWP.
• Markup Extensions for WPF parity
  I'll add here (even they were mentioned in the issue already)

• Style Binding missing
• Binding RelativeSource missing
• The ability to use various Types combined in xaml e.g. (Array with strings; e.g. <ListBox><ListBox.ItemsSource><x:Array><s:string>foo<s/:string>[...])
• AdornerItem
• Path Markup Extension of WPF

[charlesroddie]

(Not Xaml-related)
WPF has sub-pixel anti-aliasing and WinRT doesn't.

[mdtauk]

@charlesroddie I've covered that in #768

[adrientetar]

Ability to create cursors dynamically at runtime #506

[sonnemaf]

I would like:

• {x:Static}
• Bubbeling of the ButtonBase.Click event on a parent, see screenshot below
  
• Path animations
• Shape classes like Arrow, Callout, Star, etc. (Included in Blend for WPF projects)
• StringFormat property on Binding object
• DataTemplate.DataType property
  

I don't need:

• {DynamicResource}
• Tunneling of events
• PropertyTriggers, EventTriggers, DataTriggers, MultiDataTriggers. I will use the VSM
• IMultiValueConverter, I will use x:Bind instead
• FindAncestor and PreviousData RelativeSource databinding

[verelpode]

• @bschoepke mentioned VisualBrush. This is also relevant for tiled brushes. See Proposal: Bring back vector-based tiled brushes #536.

• @bschoepke also mentioned no way to Freeze. This is also relevant for sharing of PathGeometry -- you can share a frozen PathGeometry in WPF but not in UWP. See issue #827.

• WPF apps can make their own custom Controls/elements that render graphics (instead of creating child Controls or ControlTemplate), by overriding System.Windows.UIElement.OnRender(System.Windows.Media.DrawingContext). Is the equivalent ability missing in UWP? I know this is a Composition/Visual issue, but does it require access to internal/protected members? I will understand this issue much better when I can look at the source code when WinUI 3 is released.

• WPF (but not UWP) apps can measure text without disrupting the Measure/Arrange passes, by using System.Windows.Media.FormattedText. See issue #1226.

• WPF (but not UWP) apps can check and be notified when the effective visibility of an element changes. See issue #674.

• WPF apps can use Block objects to easily read and modify the contents of both editable and non-editable rich textboxes, whereas UWP only supports Block objects for RichTextBlock not RichEditBox. See issue #706.

• WPF (but not UWP) apps can skip the print dialog. See issue #672.