MauiIcons Core Markup Extension Improvements with Setters and Triggers Support

[AathifMahir]

This discussion brings together all the feedback on supporting Style Setters and Triggers to Existing MauiIcons Xaml MarkupExtension or Evolution of Xaml Markup Extension Does Fixes the Existing Pitfalls and etc..

[albyrock87]

A Markup Extension is not suited for applying values to multiple properties.
It's only purpose is to provide a single value, potentially depending on the injection context.

The current Markup Extension is trying to do something which exceeds the purpose of a markup extension and in fact this doesn't work on style Setters.

There's also a legit behavior here.

I think we should

• make the markup extension not a markup extension but simply a BindableObject, maybe renaming it to BaseIcon
• rename the Icon property here to IconValue and make it a private bindable property
• add a new Icon property as an attached one of type MauiIcon and make use of propertyChanged: callback to:
  • bind BindingContextProperty in BaseIcon to target bindable object BindingContext in order to propagate the context
  • then bind all the BaseIcon properties to the target ones depending on target type (like we're doing on the extension right now)

This is what it'd look like:

<mi:MauiIcon Icon="{mi:Cupertino Airplane}"/>
<Label mi:MauiIcon.Icon="{mi:Cupertino Airplane}"/>

[AathifMahir]

I guess you can implement IMarkupExtension instead of IMarkupExtension<T>.

If that doesn't work (but it should) you can probably create a one time binding to "." with this as source.

I Found that Ideal Solution Would be using SetBaseIconProperties, Since BaseIconExtension is Generic with Enum therefore Converting the Incoming IconExtension into BaseIconExtension is Huge Hassle, We need to have lots of Reflection to Do that.

Additionally, Would you mind explaining how we can propagate BindingContext to the Extension, I'm Pretty Sure that Could be Super Helpful for Many

[AathifMahir]

I guess you can implement IMarkupExtension instead of IMarkupExtension<T>.

If that doesn't work (but it should) you can probably create a one time binding to "." with this as source.

Updated BaseExtension with Improved Implementation, that does get rid of Old SetBaseIconProperties, Instead Passes the Existing Instance to Attached Property,

If you have time, would you be able to review the latest implementation, Thanks

[albyrock87]

@AathifMahir would you mind opening a Draft PR so I can comment on specific lines?

[AathifMahir]

@AathifMahir would you mind opening a Draft PR so I can comment on specific lines?

Sure, that works

[AathifMahir]

@AathifMahir would you mind opening a Draft PR so I can comment on specific lines?

Here's the PR
#108