Flutter苹果设备视觉扫描插件apple_vision_scanner的使用

apple_vision_scanner 是一个用于在Flutter应用中使用Apple Vision条形码扫描功能的插件。以下是该插件的详细使用说明。

apple_vision_scanner

Apple Vision 条形码扫描器是一个使Flutter应用程序能够使用 Apple Vision 条形码扫描 的插件。

• 此插件不是由Apple赞助或维护的。作者是希望为macOS创建类似Google ML Kit插件的开发者。

要求

MacOS

• 最低osx部署目标：10.13
• Xcode 13 或更新版本
• Swift 5
• ML Kit仅支持64位架构（x86_64 和 arm64）

iOS

• 最低ios部署目标：11.0
• Xcode 13 或更新版本
• Swift 5
• ML Kit仅支持64位架构（x86_64 和 arm64）

开始使用

首先需要导入 apple_vision 包：

import 'package:apple_vision/apple_vision.dart';

接下来是完整的示例代码：

import 'dart:typed_data';

import 'package:apple_vision_scanner/apple_vision_scanner.dart';
import 'package:flutter/material.dart';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  [@override](/user/override)
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: const VisionScanner(),
    );
  }
}

class VisionScanner extends StatefulWidget {
  const VisionScanner({
    Key? key,
    this.onScanned
  }) : super(key: key);

  final Function(dynamic data)? onScanned;

  [@override](/user/override)
  _VisionScanner createState() => _VisionScanner();
}

class _VisionScanner extends State<VisionScanner> {
  final GlobalKey cameraKey = GlobalKey(debugLabel: "cameraKey");
  AppleVisionScannerController visionController = AppleVisionScannerController();
  InsertCamera camera = InsertCamera();
  String? deviceId;
  bool loading = true;
  Size imageSize = const Size(640, 640 * 9 / 16);

  List<Barcode>? barcodeData;
  late double deviceWidth;
  late double deviceHeight;

  Uint8List? image;

  [@override](/user/override)
  void initState() {
    camera.setupCameras().then((value) {
      setState(() {
        loading = false;
      });
      camera.startLiveFeed((InputImage i) {
        if (i.metadata?.size != null) {
          imageSize = i.metadata!.size;
        }
        if (mounted) {
          Uint8List? image = i.bytes;
          visionController.processImage(
            image!,
            i.metadata!.size
          ).then((data) {
            barcodeData = data;
            setState(() {});
          });
        }
      });
    });
    super.initState();
  }

  [@override](/user/override)
  void dispose() {
    camera.dispose();
    super.dispose();
  }

  [@override](/user/override)
  Widget build(BuildContext context) {
    deviceWidth = MediaQuery.of(context).size.width;
    deviceHeight = MediaQuery.of(context).size.height;
    return Stack(
      children: [
        SizedBox(
          width: imageSize.width,
          height: imageSize.height,
          child: loading ? Container() : CameraSetup(camera: camera, size: imageSize,)
        ),
      ] + showRects()
    );
  }

  List<Widget> showRects() {
    if (barcodeData == null || barcodeData!.isEmpty) return [];
    List<Widget> widgets = [];

    for (int i = 0; i < barcodeData!.length; i++) {
      widgets.add(
        Positioned(
          top: barcodeData![i].boundingBox!.top,
          left: barcodeData![i].boundingBox!.left,
          child: Container(
            width: barcodeData![i].boundingBox!.width,
            height: barcodeData![i].boundingBox!.height,
            decoration: BoxDecoration(
              color: Colors.transparent,
              border: Border.all(width: 1, color: Colors.green),
              borderRadius: BorderRadius.circular(5)
            ),
            child: Text(
              '${barcodeData![i].displayValue}: ${barcodeData![i].type}',
              style: const TextStyle(
                color: Colors.white,
                fontSize: 12
              ),
            ),
          )
        )
      );
    }
    return widgets;
  }

  Widget loadingWidget() {
    return Container(
      width: deviceWidth,
      height: deviceHeight,
      color: Theme.of(context).canvasColor,
      alignment: Alignment.center,
      child: const CircularProgressIndicator(color: Colors.blue)
    );
  }
}