#20 - Image Widget to dart:ui Image for Flutter

Data: 2018-08-04 12:00 - dart

Helper to convert a widget image into a dart:ui image.

import 'dart:ui' as ui;

import 'package:flutter/painting.dart';
import 'package:flutter/widgets.dart' as widget;

/// Helper to convert a widget image into a dart:ui image
///
/// The resulting image will be sent in [callback].
///
/// The returned function allows to unregister the listener in case it is not
/// needed before the callback is called.
Function() convertImage(widget.Image image, Function(ui.Image) callback) {
  final ImageStream newStream = image.image.resolve(ImageConfiguration.empty);
  Function(ImageInfo, bool) listener;
  listener = (ImageInfo info, bool synchronousCall) {
    callback(info?.image);
    newStream.removeListener(listener);
  };

  newStream.addListener(listener);
  return () => newStream.removeListener(listener);
}

Previous snippet | Next snippet