Stuck on an issue?

Lightrun Answers was designed to reduce the constant googling that comes with debugging 3rd party libraries. It collects links to all the places you might be looking at while hunting down a tough bug.

And, if you’re still stuck at the end, we’re happy to hop on a call to see how we can help out.

Cannot set AppBarButton Icon from Style

See original GitHub issue

Hi @Kinnara,

thank you for all your work on this great library!

I tried to define a Style for an AppBarButton that speciffes the AppBarButton.Icon property. Apparently, the Style only works on a single instance of the button. If multiple buttons apply the same style, then only the last button will display the icon.

The Icon property is of type IconElement : FrameworkElement. AFAIK, an element can only be used once in the visual tree. I haven’t been able to find a workaround for this current limitation.

Usually, control properties are either Freezable or a pair of { Content, ContentTemplate }, to allow templating.

Maybe the new IconSource provides an elegant solution to this problem?

Issue Analytics

State:
Created 3 years ago
Reactions:1
Comments:8 (5 by maintainers)

Top GitHub Comments

2reactions

Kinnaracommented, Dec 6, 2020

This is actually possible in WPF, thanks to the x:Shared attribute:

<ui:SymbolIcon x:Key="SaveIcon" Symbol="Save" x:Shared="False" />

<Style x:Key="SaveButtonStyle" TargetType="ui:AppBarButton">
    <Setter Property="Icon" Value="{StaticResource SaveIcon}" />
    <Setter Property="Label" Value="Save" />
</Style>

<ui:CommandBar>
    <ui:AppBarButton Style="{StaticResource SaveButtonStyle}" />
    <ui:AppBarButton Style="{StaticResource SaveButtonStyle}" />
    <ui:AppBarButton Style="{StaticResource SaveButtonStyle}" />
</ui:CommandBar>

1reaction

wmruttencommented, Dec 18, 2020

Hi @Kinnara , thank you for your feedback.

Indeed, the issue is related to resource sharing. I am aware of the x:Shared attribute, it fixes the problem for global resources declared in XAML.

In this case, I was trying to provide the icon resource in a Style through a (custom) markup extension that returns a (custom) FontIcon, programmatically. The markup extension would need to return a separate FontIcon instance for each target control that the style is applied to, similar to x:Shared behavior. Maybe this is possible by hooking the target control from the markup extension, but I didn’t explore any further.

Nonetheless, I understand the motivations for this library to stay close to the original UWP interface and I’m perfectly happy w/o support for AppBarButton styling.

Thanks for all you hard work, guys. This library provides great UI improvements that are happily received by our app users. Quite amazing to see WinUI design running on an old Windows 7 (!) machine.

Kudos and keep it up!