45 lines
1.2 KiB
Dart
45 lines
1.2 KiB
Dart
import 'package:flutter/material.dart';
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class CrosshairPainter extends CustomPainter {
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@override
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void paint(Canvas canvas, Size size) {
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// 十字中心坐标（精准对齐容器中心）
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final centerX = size.width / 2;
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final centerY = size.height / 2;
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// 十字画笔样式（红色醒目，匹配原有定位标风格）
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final paint = Paint()
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..color = Colors.red
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..strokeWidth =
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2.0 // 十字线条宽度
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..strokeCap = StrokeCap.round; // 线条端点圆润，更美观
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// ========== 绘制水平横线（─） ==========
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canvas.drawLine(
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Offset(0, centerY), // 左端点
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Offset(size.width, centerY), // 右端点
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paint,
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);
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// ========== 绘制垂直竖线（│） ==========
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canvas.drawLine(
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Offset(centerX, 0), // 上端点
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Offset(centerX, size.height), // 下端点
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paint,
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);
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// 可选：中心小圆点（强化中心定位）
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final centerDotPaint = Paint()
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..color = Colors.white
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..style = PaintingStyle.fill;
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canvas.drawCircle(
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Offset(centerX, centerY),
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1.5, // 中心圆点半径
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centerDotPaint,
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);
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}
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@override
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bool shouldRepaint(covariant CrosshairPainter oldDelegate) => false;
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}
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