mobile_scanner_overlay.dart
6.41 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
import 'package:flutter/material.dart';
import 'package:mobile_scanner/mobile_scanner.dart';
import 'package:mobile_scanner_example/scanner_error_widget.dart';
class BarcodeScannerWithOverlay extends StatefulWidget {
@override
_BarcodeScannerWithOverlayState createState() =>
_BarcodeScannerWithOverlayState();
}
class _BarcodeScannerWithOverlayState extends State<BarcodeScannerWithOverlay> {
String overlayText = "Please scan QR Code";
bool camStarted = false;
BarcodeCapture? currentBarcodeCapture;
final MobileScannerController controller = MobileScannerController(
facing: CameraFacing.back,
formats: const [BarcodeFormat.qrCode],
autoStart: false,
);
@override
dispose() {
controller.dispose();
super.dispose();
}
void startCamera() {
setState(() {
camStarted = !camStarted;
controller.start();
});
}
void onBarcodeDetect(BarcodeCapture barcodeCapture) {
setState(() {
currentBarcodeCapture = barcodeCapture;
overlayText = barcodeCapture.barcodes.last.displayValue!;
});
}
@override
Widget build(BuildContext context) {
final scanWindow = Rect.fromCenter(
center: MediaQuery.of(context).size.center(Offset.zero),
width: 200,
height: 200,
);
return Scaffold(
appBar: AppBar(
title: const Text('Scanner with Overlay Example app'),
),
body: Center(
child: Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Expanded(
child: camStarted
? Stack(
fit: StackFit.expand,
children: [
Center(
child: MobileScanner(
fit: BoxFit.contain,
onDetect: onBarcodeDetect,
overlay: Padding(
padding: const EdgeInsets.all(16.0),
child: Align(
alignment: Alignment.bottomCenter,
child: Opacity(
opacity: 0.7,
child: Text(
overlayText,
style: const TextStyle(
backgroundColor: Colors.black26,
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 24,
overflow: TextOverflow.ellipsis,
),
maxLines: 1,
),
),
),
),
controller: controller,
scanWindow: scanWindow,
errorBuilder: (context, error, child) {
return ScannerErrorWidget(error: error);
},
),
),
CustomPaint(
painter: ScannerOverlay(scanWindow),
),
Padding(
padding: const EdgeInsets.all(16.0),
child: Align(
alignment: Alignment.bottomCenter,
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: [
IconButton(
onPressed: () => controller.toggleTorch(),
icon: Icon(
Icons.flashlight_on,
color: controller.torchEnabled
? Colors.yellow
: Colors.black,
),
),
IconButton(
onPressed: () => controller.switchCamera(),
icon: const Icon(
Icons.cameraswitch_rounded,
color: Colors.white,
),
),
],
),
),
),
],
)
: const Center(
child: Text("Tap on Camera to activate QR Scanner")),
),
],
),
),
floatingActionButton: camStarted
? null
: FloatingActionButton(
child: const Icon(
Icons.camera_alt,
),
onPressed: () {
startCamera();
},
),
);
}
}
class ScannerOverlay extends CustomPainter {
ScannerOverlay(this.scanWindow);
final Rect scanWindow;
@override
void paint(Canvas canvas, Size size) {
final backgroundPath = Path()..addRect(Rect.largest);
final cutoutPath = Path()..addRect(scanWindow);
final backgroundPaint = Paint()
..color = Colors.black.withOpacity(0.5)
..style = PaintingStyle.fill
..blendMode = BlendMode.dstOut;
final backgroundWithCutout = Path.combine(
PathOperation.difference,
backgroundPath,
cutoutPath,
);
// Create a Paint object for the white border
final borderPaint = Paint()
..color = Colors.white
..style = PaintingStyle.stroke
..strokeWidth = 4.0; // Adjust the border width as needed
// Calculate the border rectangle with rounded corners
// Adjust the radius as needed
final borderRect = RRect.fromRectAndCorners(
scanWindow,
topLeft: const Radius.circular(12.0),
topRight: const Radius.circular(12.0),
bottomLeft: const Radius.circular(12.0),
bottomRight: const Radius.circular(12.0),
);
// Draw the white border
canvas.drawPath(backgroundWithCutout, backgroundPaint);
canvas.drawRRect(borderRect, borderPaint);
}
@override
bool shouldRepaint(covariant CustomPainter oldDelegate) {
return false;
}
}