Files
iroute/packages/idraw/lib/p04/s02.dart
toly 25e51d789f 24
2023-12-11 21:53:27 +08:00

119 lines
2.8 KiB
Dart

import 'dart:async';
import 'dart:math';
import 'dart:typed_data';
import 'dart:ui' as ui;
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import '../components/coordinate.dart';
/// create by 张风捷特烈 on 2020-03-19
/// contact me by email 1981462002@qq.com
/// 说明: 纸
class Paper extends StatefulWidget {
const Paper({super.key});
@override
_PaperState createState() => _PaperState();
}
class _PaperState extends State<Paper> {
@override
void initState() {
super.initState();
_loadImage();
}
void _loadImage() async {
_image =
await loadImageFromAssets('assets/images/wy_300x200.jpg');
setState(() {});
}
ui.Image? _image;
@override
Widget build(BuildContext context) {
return Container(
color: Colors.white,
child: CustomPaint(
painter: PaperPainter(
_image,
)));
}
//读取 assets 中的图片
Future<ui.Image>? loadImageFromAssets(String path) async {
ByteData data = await rootBundle.load(path);
return decodeImageFromList(data.buffer.asUint8List());
}
}
class PaperPainter extends CustomPainter {
late Paint _paint;
final double strokeWidth = 0.5;
final Color color = Colors.blue;
final ui.Image? image;
final Coordinate coordinate = Coordinate();
PaperPainter(this.image) {
_paint = Paint()
..style = PaintingStyle.fill
..strokeWidth = strokeWidth
..color = color;
}
@override
void paint(Canvas canvas, Size size) {
coordinate.paint(canvas, size);
canvas.translate(size.width / 2, size.height / 2);
_drawImage(canvas);
_drawImageRect(canvas);
}
@override
bool shouldRepaint(PaperPainter oldDelegate) => image != oldDelegate.image;
void _drawImage(Canvas canvas) {
if (image != null) {
canvas.drawImage(
image!, Offset(-image!.width / 2, -image!.height / 2), _paint);
}
}
void _drawImageRect(Canvas canvas) {
if (image != null) {
canvas.drawImageRect(
image!,
Rect.fromCenter(
center: Offset(image!.width / 2, image!.height / 2),
width: 60,
height: 60),
Rect.fromLTRB(0, 0, 100, 100).translate(200, 0),
_paint);
canvas.drawImageRect(
image!,
Rect.fromCenter(
center: Offset(image!.width / 2, image!.height / 2 - 60),
width: 60,
height: 60),
Rect.fromLTRB(0, 0, 100, 100).translate(-280, -100),
_paint);
canvas.drawImageRect(
image!,
Rect.fromCenter(
center: Offset(image!.width / 2 + 60, image!.height / 2),
width: 60,
height: 60),
Rect.fromLTRB(0, 0, 100, 100).translate(-280, 50),
_paint);
}
}
}