Modify ColorConverters to support two-way bindings

[eduardoagr]

Description of Change

Added a new HexToColor converter

Linked Issues

We need a way to convert the RGB color to a Maui color, that Labels Buttons, etc. understand.

• Fixes #

PR Checklist

• Has a linked Issue, and the Issue has been approved(bug) or Championed (feature/proposal)
• Has tests (if omitted, state reason in description)
• Has samples (if omitted, state reason in description)
• Rebased on top of main at time of PR
• Changes adhere to coding standard
• Documentation created or updated: https://github.com/MicrosoftDocs/CommunityToolkit/pulls

Additional information

[bijington]

@brminnick there is a discussion where I agreed there is a bug in our converters, they are currently only one way so I suggested we would make them two way.

[brminnick]

Apologies. Re-opening.

Please update the PR Description. It is currently just the blank template.

[eduardoagr]

Apologies. Re-opening.

Please update the PR Description. It is currently just the blank template.

how do I do that, this is my first contibrution

also here is the discution

#1496

[bijington]

@eduardoagr thank you for making the effort to provide this implementation. I am hopeful we can make it a more complete offering for developers to use our Color based converters in the toolkit.

I would like to refer back to my point in our original discussion though:

I am happy with the idea of introducing this and in fact we don't need to introduce new converters, I believe we just need to modify our existing converters (e.g. ColorToRgbStringConverter, etc.) to be two way converters. Currently they only convert from target to source which only covers the scenario of getting the Color into the data model and not back to the UI.

I think the changes that we will want to make would be to modify the classes in this file:
https://github.com/CommunityToolkit/Maui/blob/main/src/CommunityToolkit.Maui/Converters/ColorToStringConverter.shared.cs
to inherit from type BaseConverter rather than BaseConverterOneWay as they currently do.

Do you think you would be happy to make those changes instead of introducing a new converter like the initial work does inside this PR?

[eduardoagr]

Aplogies for the mistake, I updated the template

I also want to update the documentation for converter, how I can do that?

I fout out hat in the documentation, there is only the guide of how to use this is XAML pages, but we can also make it globally

[eduardoagr]

Done

[bijington]

@eduardoagr sorry I didn't fully explain everything that was required because I thought the compiler would have provided the guidance. By changing the converters base class from BaseConverterOneWay to BaseConverter you will need to provide an implementation of the ConvertBackTo method. This will need to be the reverse of the ConvertFrom in each converter. This will then result in the converters providing a row way binding support and solving the issue that you originally came across. Looking at the build errors you will also need to implement the DefaultConvertBackReturnValue property on each converter.

As for the documentation we have a separate repository where you can submit a PR to. The repo is at: https://github.com/MicrosoftDocs/CommunityToolkit
I haven't checked the details directly but I think we just need to remove any mention of the converters being one-way in the documentation pages.

[eduardoagr]

Do you think we can schedule a team call sometime, to have more instrutin I also wanted t talk to you abount including a template that already includes the MVVM Comunity toolkit and Maui Community toolkit

[bijington]

Yes I'd be happy to join a call and talk through the changes if that helps. We do also have a Discord server that provides a mechanism for discussing contributions among other things: https://discord.gg/PppdVjWA

As for the template though it's not something we will implement however you can use the extension mentioned in your original discussion on the topic: #1505

[eduardoagr]

what is yur timezone, so I can program the tams metting

[VladislavAntonyuk]

The implementation looks not finished. You changed Rgb converter to BaseConverter, but Rgba remains BaseOneWayConverter.
also can we use Color.FromRgba(value) instead of Color.Parse?

[bijington]

I'm going to try and jump in this and get it finished off

[bijington]

Color.FromRgba

Color.FromRgba doesn't support converting from the format: RGBA(0,0,0,0)

[bijington]

@eduardoagr apologies for the delay in getting this sorted. Would you mind please agreeing to the CLA?

[eduardoagr]

How do I sign

[eduardoagr]

@dotnet-policy-service agree

[eduardoagr]

I just sign

[bijington]

I just sign

That's great thank you

[bijington]

Thanks for this @eduardoagr. I'll aim to update our docs shortly