ImageUrlBuilder typedef

ImageUrlBuilder = String Function(String src, int width)

Function signature for generating width-specific image URLs for responsive srcset sets.

Receives the original image src and a target integer width, returning the transformed URL. Used by buildSrcSet, bloomImage, and PictureSource to generate responsive image variants.

String cdnBuilder(String src, int width) =>
    'https://images.example.com/cdn-cgi/image/width=$width,format=auto/$src';

final srcset = buildSrcSet('/hero.jpg', [400, 800, 1200], urlBuilder: cdnBuilder);

See also:

• defaultImageUrlBuilder, the standard query-parameter builder.
• buildSrcSet, which converts a list of widths into a srcset attribute.

Implementation

typedef ImageUrlBuilder = String Function(String src, int width);