124 lines
3.6 KiB
Dart
124 lines
3.6 KiB
Dart
import 'dart:async';
|
|
import 'dart:ui' as ui show Codec;
|
|
|
|
import 'package:aves/model/image_entry.dart';
|
|
import 'package:aves/services/image_file_service.dart';
|
|
import 'package:flutter/foundation.dart';
|
|
import 'package:flutter/material.dart';
|
|
|
|
class RegionProvider extends ImageProvider<RegionProviderKey> {
|
|
final RegionProviderKey key;
|
|
|
|
RegionProvider(this.key) : assert(key != null);
|
|
|
|
@override
|
|
Future<RegionProviderKey> obtainKey(ImageConfiguration configuration) {
|
|
return SynchronousFuture<RegionProviderKey>(key);
|
|
}
|
|
|
|
@override
|
|
ImageStreamCompleter load(RegionProviderKey key, DecoderCallback decode) {
|
|
return MultiFrameImageStreamCompleter(
|
|
codec: _loadAsync(key, decode),
|
|
scale: key.scale,
|
|
informationCollector: () sync* {
|
|
yield ErrorDescription('uri=${key.uri}, rect=${key.rect}');
|
|
},
|
|
);
|
|
}
|
|
|
|
Future<ui.Codec> _loadAsync(RegionProviderKey key, DecoderCallback decode) async {
|
|
final uri = key.uri;
|
|
final mimeType = key.mimeType;
|
|
try {
|
|
final bytes = await ImageFileService.getRegion(
|
|
uri,
|
|
mimeType,
|
|
key.rotationDegrees,
|
|
key.isFlipped,
|
|
key.sampleSize,
|
|
key.rect,
|
|
taskKey: key,
|
|
);
|
|
if (bytes == null) {
|
|
throw StateError('$uri ($mimeType) region loading failed');
|
|
}
|
|
return await decode(bytes);
|
|
} catch (error) {
|
|
debugPrint('$runtimeType _loadAsync failed with mimeType=$mimeType, uri=$uri, error=$error');
|
|
throw StateError('$mimeType region decoding failed');
|
|
}
|
|
}
|
|
|
|
@override
|
|
void resolveStreamForKey(ImageConfiguration configuration, ImageStream stream, RegionProviderKey key, ImageErrorListener handleError) {
|
|
ImageFileService.resumeLoading(key);
|
|
super.resolveStreamForKey(configuration, stream, key, handleError);
|
|
}
|
|
|
|
void pause() => ImageFileService.cancelRegion(key);
|
|
}
|
|
|
|
class RegionProviderKey {
|
|
final String uri, mimeType;
|
|
final int rotationDegrees, sampleSize;
|
|
final bool isFlipped;
|
|
final Rect rect;
|
|
final double scale;
|
|
|
|
const RegionProviderKey({
|
|
@required this.uri,
|
|
@required this.mimeType,
|
|
@required this.rotationDegrees,
|
|
@required this.isFlipped,
|
|
@required this.sampleSize,
|
|
@required this.rect,
|
|
this.scale = 1.0,
|
|
}) : assert(uri != null),
|
|
assert(mimeType != null),
|
|
assert(rotationDegrees != null),
|
|
assert(isFlipped != null),
|
|
assert(sampleSize != null),
|
|
assert(rect != null),
|
|
assert(scale != null);
|
|
|
|
// do not store the entry as it is, because the key should be constant
|
|
// but the entry attributes may change over time
|
|
factory RegionProviderKey.fromEntry(
|
|
ImageEntry entry, {
|
|
@required int sampleSize,
|
|
@required Rect rect,
|
|
}) {
|
|
return RegionProviderKey(
|
|
uri: entry.uri,
|
|
mimeType: entry.mimeType,
|
|
rotationDegrees: entry.rotationDegrees,
|
|
isFlipped: entry.isFlipped,
|
|
sampleSize: sampleSize,
|
|
rect: rect,
|
|
);
|
|
}
|
|
|
|
@override
|
|
bool operator ==(Object other) {
|
|
if (other.runtimeType != runtimeType) return false;
|
|
return other is RegionProviderKey && other.uri == uri && other.mimeType == mimeType && other.rotationDegrees == rotationDegrees && other.isFlipped == isFlipped && other.sampleSize == sampleSize && other.rect == rect && other.scale == scale;
|
|
}
|
|
|
|
@override
|
|
int get hashCode => hashValues(
|
|
uri,
|
|
mimeType,
|
|
rotationDegrees,
|
|
isFlipped,
|
|
mimeType,
|
|
sampleSize,
|
|
rect,
|
|
scale,
|
|
);
|
|
|
|
@override
|
|
String toString() {
|
|
return 'RegionProviderKey(uri=$uri, mimeType=$mimeType, rotationDegrees=$rotationDegrees, isFlipped=$isFlipped, sampleSize=$sampleSize, rect=$rect, scale=$scale)';
|
|
}
|
|
}
|