aves/lib/thumbnail.dart

110 lines
3.3 KiB
Dart

import 'dart:math';
import 'dart:typed_data';
import 'package:aves/model/image_decode_service.dart';
import 'package:aves/model/image_entry.dart';
import 'package:aves/model/mime_types.dart';
import 'package:flutter/material.dart';
import 'package:transparent_image/transparent_image.dart';
class Thumbnail extends StatefulWidget {
final ImageEntry entry;
final double extent;
final double devicePixelRatio;
const Thumbnail({
Key key,
@required this.entry,
@required this.extent,
@required this.devicePixelRatio,
}) : super(key: key);
@override
ThumbnailState createState() => ThumbnailState();
}
class ThumbnailState extends State<Thumbnail> {
Future<Uint8List> _byteLoader;
String get mimeType => widget.entry.mimeType;
String get uri => widget.entry.uri;
@override
void initState() {
super.initState();
initByteLoader();
}
@override
void didUpdateWidget(Thumbnail oldWidget) {
super.didUpdateWidget(oldWidget);
if (uri == oldWidget.entry.uri && widget.extent == oldWidget.extent) return;
initByteLoader();
}
initByteLoader() {
final dim = (widget.extent * widget.devicePixelRatio).round();
_byteLoader = ImageDecodeService.getImageBytes(widget.entry, dim, dim);
}
@override
void dispose() {
ImageDecodeService.cancelGetImageBytes(uri);
super.dispose();
}
@override
Widget build(BuildContext context) {
final isVideo = mimeType.startsWith(MimeTypes.MIME_VIDEO);
final isGif = mimeType == MimeTypes.MIME_GIF;
final iconSize = widget.extent / 4;
return Container(
decoration: BoxDecoration(
border: Border.all(
color: Colors.grey.shade700,
width: 0.5,
),
),
child: FutureBuilder(
future: _byteLoader,
builder: (futureContext, AsyncSnapshot<Uint8List> snapshot) {
final bytes = (snapshot.connectionState == ConnectionState.done && !snapshot.hasError) ? snapshot.data : kTransparentImage;
return Stack(
alignment: AlignmentDirectional.bottomStart,
children: [
Hero(
tag: uri,
child: LayoutBuilder(builder: (context, constraints) {
// during hero animation back from a fullscreen image,
// the image covers the whole screen (because of the 'fit' prop and the full screen hero constraints)
// so we wrap the image to apply better constraints
final dim = min(constraints.maxWidth, constraints.maxHeight);
return Container(
alignment: Alignment.center,
constraints: BoxConstraints.tight(Size(dim, dim)),
child: Image.memory(
bytes,
width: dim,
height: dim,
fit: BoxFit.cover,
),
);
}),
),
if (isVideo)
Icon(
Icons.play_circle_outline,
size: iconSize,
),
if (isGif)
Icon(
Icons.gif,
size: iconSize,
),
],
);
}),
);
}
}