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ColorToRgbaStringConverter

The ColorToRgbaStringConverter is a converter that allows users to convert a Color value binding to its RGBA string equivalent in the format: RGB(red,green,blue,alpha) where red, green and blue will be a value between 0 and 255, and alpha is a value between 0 and 1 (e.g. RGB(255,0,0,1) for Colors.Red.

The Convert method returns the supplied Color value converted to its RGB string equivalent.

The ConvertBack method returns the RGB string value converted to a Color.

BaseConverter Properties

The following properties are implemented in the base class, public abstract class BaseConverter:

Property Description
DefaultConvertReturnValue Default value to return when IValueConverter.Convert(object?, Type, object?, CultureInfo?) throws an Exception. This value is used when CommunityToolkit.Maui.Options.ShouldSuppressExceptionsInConverters is set to true.
DefaultConvertBackReturnValue Default value to return when IValueConverter.ConvertBack(object?, Type, object?, CultureInfo?) throws an Exception. This value is used when CommunityToolkit.Maui.Options.ShouldSuppressExceptionsInConverters is set to true.

ICommunityToolkitValueConverter Properties

The following properties are implemented in the public interface ICommunityToolkitValueConverter:

Property Type Description
DefaultConvertReturnValue object? Default value to return when IValueConverter.Convert(object?, Type, object?, CultureInfo?) throws an Exception. This value is used when CommunityToolkit.Maui.Options.ShouldSuppressExceptionsInConverters is set to true.
DefaultConvertBackReturnValue object? Default value to return when IValueConverter.ConvertBack(object?, Type, object?, CultureInfo?) throws an Exception. This value is used when CommunityToolkit.Maui.Options.ShouldSuppressExceptionsInConverters is set to true.

Syntax

The following examples will show how to use the ColorToRgbaStringConverter to display the RGBA equivalent string of a specific Color.

XAML

Including the XAML namespace

In order to use the toolkit in XAML the following xmlns needs to be added into your page or view:

xmlns:toolkit="http://schemas.microsoft.com/dotnet/2022/maui/toolkit"

Therefore the following:

<ContentPage
    x:Class="CommunityToolkit.Maui.Sample.Pages.MyPage"
    xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml">

</ContentPage>

Would be modified to include the xmlns as follows:

<ContentPage
    x:Class="CommunityToolkit.Maui.Sample.Pages.MyPage"
    xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
    xmlns:toolkit="http://schemas.microsoft.com/dotnet/2022/maui/toolkit">

</ContentPage>

Using the ColorToRgbaStringConverter

The ColorToRgbaStringConverter can be used as follows in XAML:

<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:toolkit="http://schemas.microsoft.com/dotnet/2022/maui/toolkit"
             x:Class="CommunityToolkit.Maui.Sample.Pages.Converters.ColorToRgbaStringConverterPage">

    <ContentPage.Resources>
        <ResourceDictionary>
            <toolkit:ColorToRgbaStringConverter x:Key="ColorToRgbaStringConverter" />
        </ResourceDictionary>
    </ContentPage.Resources>

    <VerticalStackLayout>
        <Label Text="My favourite Color is:" />

        <Label Text="{Binding MyFavoriteColor, Converter={StaticResource ColorToRgbaStringConverter}}" />
    </VerticalStackLayout>

</ContentPage>

C#

The ColorToRgbaStringConverter can be used as follows in C#:

class ColorToRgbaStringConverterPage : ContentPage
{
    public ColorToRgbaStringConverterPage()
    {
        var label = new Label();

	label.SetBinding(
		Label.TextProperty,
		new Binding(
			nameof(ViewModel.MyFavoriteColor),
			converter: new ColorToRgbaStringConverter()));

	Content = new VerticalStackLayout
	{
		Children =
		{
			new Label { Text = "My favourite Color is:" },
			label
		}
	};
    }
}

C# Markup

Our CommunityToolkit.Maui.Markup package provides a much more concise way to use this converter in C#.

using CommunityToolkit.Maui.Markup;

class ColorToRgbaStringConverterPage : ContentPage
{
    public ColorToRgbaStringConverterPage()
    {
        Content = new VerticalStackLayout
        {
            Children =
            {
                new Label()
                    .Text("My favourite Color is:"),
                new Label()
                    .Bind(
                        Label.TextProperty,
                        static (ViewModel vm) => vm.MyFavoriteColor,
                        converter: new ColorToRgbaStringConverter())
            }
        };
    }
}

Examples

You can find an example of this converter in action in the .NET MAUI Community Toolkit Sample Application.

API

You can find the source code for ColorToRgbaStringConverter over on the .NET MAUI Community Toolkit GitHub repository.