fake_image_provider.dart 1.12 KB
Newer Older
Ian Hickson's avatar
Ian Hickson committed
1
// Copyright 2014 The Flutter Authors. All rights reserved.
2 3 4 5 6 7
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:ui' as ui show Codec;

import 'package:flutter/foundation.dart';
8
import 'package:flutter/painting.dart';
9 10 11 12 13 14

/// An image provider implementation for testing that is using a [ui.Codec]
/// that it was given at construction time (typically the job of real image
/// providers is to resolve some data and instantiate a [ui.Codec] from it).
class FakeImageProvider extends ImageProvider<FakeImageProvider> {

15
  const FakeImageProvider(this._codec, { this.scale = 1.0 });
16 17 18 19 20 21 22 23

  final ui.Codec _codec;

  /// The scale to place in the [ImageInfo] object of the image.
  final double scale;

  @override
  Future<FakeImageProvider> obtainKey(ImageConfiguration configuration) {
24
    return SynchronousFuture<FakeImageProvider>(this);
25 26 27
  }

  @override
28
  ImageStreamCompleter load(FakeImageProvider key, DecoderCallback decode) {
29
    assert(key == this);
30 31
    return MultiFrameImageStreamCompleter(
      codec: SynchronousFuture<ui.Codec>(_codec),
32
      scale: scale,
33 34 35
    );
  }
}