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9f228349e9
Using ImageResource solves two problems: 1) Listeners can be notified synchronously when the sky.Image is already available. This change removes flash of 0x0 layout when moving an already-cached image around in the render tree. 2) In the future, when we support animated images, we can notify listeners multiple times whenever a new image is available.
29 lines
953 B
Dart
29 lines
953 B
Dart
// Copyright 2015 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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import 'dart:async';
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import 'dart:collection';
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import 'dart:sky' as sky;
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import 'package:mojo/mojo/url_response.mojom.dart';
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import 'package:sky/base/image_resource.dart';
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import 'package:sky/mojo/net/fetch.dart';
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final HashMap<String, ImageResource> _cache = new Map<String, ImageResource>();
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ImageResource load(String url) {
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return _cache.putIfAbsent(url, () {
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Completer<sky.Image> completer = new Completer<sky.Image>();
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fetchUrl(url).then((UrlResponse response) {
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if (response.statusCode >= 400) {
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print("Failed (${response.statusCode}) to load image ${url}");
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completer.complete(null);
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} else {
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new sky.ImageDecoder(response.body.handle.h, completer.complete);
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}
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});
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return new ImageResource(completer.future);
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});
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}
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