resolve method

PictureStream resolve(PictureConfiguration picture, { PictureErrorListener? onError, })

Resolves this Picture provider using the given configuration, returning an PictureStream.

This is the public entry-point of the PictureProvider class hierarchy.

Subclasses should implement obtainKey and load, which are used by this method.

Implementation

PictureStream resolve(PictureConfiguration picture,
    {PictureErrorListener? onError}) {
  // ignore: unnecessary_null_comparison
  assert(picture != null);
  final PictureStream stream = PictureStream();
  T? obtainedKey;
  obtainKey(picture).then<void>(
    (T key) {
      obtainedKey = key;
      stream.setCompleter(
        cache.putIfAbsent(
          key!,
          () => load(key, onError: onError),
        ),
      );
    },
  ).catchError((Object exception, StackTrace stack) async {
    if (onError != null) {
      onError(exception, stack);
      return;
    }
    FlutterError.reportError(FlutterErrorDetails(
        exception: exception,
        stack: stack,
        library: 'SVG',
        context: ErrorDescription('while resolving a picture'),
        silent: true, // could be a network error or whatnot
        informationCollector: () sync* {
          yield DiagnosticsProperty<PictureProvider>(
              'Picture provider', this);
          yield DiagnosticsProperty<T>('Picture key', obtainedKey,
              defaultValue: null);
        }));
  });
  return stream;
}