ReplaceStringMap doesn't work

I’d like to replace a color within an SVG file.

As far as I found out, ReplaceStringMap is the way to go.

The following example should display a blue rectangle, but it’s red (as defined in the SVG file):

The SVG file contains a red rectangle:

<svg viewBox="0 0 24 24">
  <rect fill="#ff0000" width="24" height="24" />
</svg>

Code to display the image - note the ReplaceStringMap should replace red by blue:

  public partial class MainPage : ContentPage {
    public MainPage() {
      var layout = new StackLayout();

      layout.Children.Add(new SvgCachedImage {
        Source = "resource://Foo.Images.test.svg",
        ReplaceStringMap = new Dictionary<string, string> { { "ff0000", "0000ff"} },
        WidthRequest = 98, HeightRequest = 98
      });

      this.Content = layout;
    }

The result is a red rectangle instead of a blue one. Am I doing something wrong?

(PS.: I also tried calling ReloadImage() but that didn’t help either)

Xamarin.FFImageLoading.Svg version is 2.2.25.

[stmax82]

Yes all projects use the same version.

It looks like the order in which the properties are set matters:

This one does not work (image stays red):

      layout.Children.Add(new SvgCachedImage {
        Source = "resource://ReplaceStringMapProblem.test.svg",
        ReplaceStringMap = new Dictionary<string, string> { { "ff0000", "0000ff" } },
        WidthRequest = 98, HeightRequest = 98
      });

This one works (image turns blue):

      layout.Children.Add(new SvgCachedImage {
        ReplaceStringMap = new Dictionary<string, string> { { "ff0000", "0000ff" } },
        Source = "resource://ReplaceStringMapProblem.test.svg",
        WidthRequest = 98, HeightRequest = 98
      });

So it seems like the replacement does not work when the ReplaceStringMap property is set after the Source property.

[andreysilov]

For me it works on both platforms (iOS and Android):

if (Source is SvgImageSource source)
{
    var colorMap = new Dictionary<string, string> { { "regex:fill=\"#(?:[0-9a-fA-F]{3}){1,2}\"", $"fill=\"{color.ToHex()}\"" } };
    source.ReplaceStringMap = colorMap;
    ReplaceStringMap = colorMap;
}