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flutter开发实战-flutter二维码条形码扫一扫功能实现

flutter开发实战-flutter二维码扫一扫功能实现，要使用到摄像头的原生的功能，使用的是插件：scan

效果图如下

一、扫一扫插件scan

  # 扫一扫scan: ^1.6.0

1.1 iOS权限设置

<key>NSCameraUsageDescription</key>
<string>Your Description</string><key>io.flutter.embedded_views_preview</key>
<string>YES</string>

1.2 android权限设置

<uses-permission android:name="android.permission.CAMERA" /><application><meta-dataandroid:name="flutterEmbedding"android:value="2" />
</application>

1.3 使用ScanView的widget

ScanController controller = ScanController();
String qrcode = 'Unknown';Container(width: 250, // custom wrap sizeheight: 250,child: ScanView(controller: controller,
// custom scan area, if set to 1.0, will scan full areascanAreaScale: .7,scanLineColor: Colors.green.shade400,onCapture: (data) {// do something},),
),

扫一扫Widget使用ScanController来做响应的控制

暂停/恢复camera

controller.pause();
controller.resume();

识别图片的二维码结果

String result = await Scan.parse(imagePath);

闪光灯切换

controller.toggleTorchMode();

二、代码实现

实现自定义扫码的appBar

class QrScanAppBar extends StatefulWidget {const QrScanAppBar({Key? key,required this.toolbarHeight,this.elevation,this.backgroundColor,this.leadingWidget,this.trailingWidget,this.centerWidget,this.brightness,this.padding, this.barPadding,}) : super(key: key);final double toolbarHeight;final double? elevation;final Color? backgroundColor;final Widget? leadingWidget;final Widget? trailingWidget;final Widget? centerWidget;final Brightness? brightness;final EdgeInsetsGeometry? padding;final EdgeInsetsGeometry? barPadding;@overrideState<QrScanAppBar> createState() => _QrScanAppBarState();
}class _QrScanAppBarState extends State<QrScanAppBar> {@overrideWidget build(BuildContext context) {final SystemUiOverlayStyle overlayStyle =widget.brightness == Brightness.dark? SystemUiOverlayStyle.light: SystemUiOverlayStyle.dark;Widget leadingWidget = (widget.leadingWidget ?? Container());Widget centerWidget = (widget.centerWidget ?? Container());Widget trailingWidget = (widget.trailingWidget ?? Container());return AnnotatedRegion<SystemUiOverlayStyle>(//套AnnotatedRegion是为了增加状态栏控制value: overlayStyle,child: Material(//套Material是为了增加elevationelevation: widget.elevation ?? 0,color: Colors.transparent,child: Container(padding: widget.padding,height: widget.toolbarHeight + ScreenUtil().statusBarHeight,decoration: BoxDecoration(color: widget.backgroundColor,),child: Column(mainAxisAlignment: MainAxisAlignment.center,crossAxisAlignment: CrossAxisAlignment.center,children: [Container(height: ScreenUtil().statusBarHeight,),Expanded(child: Container(padding: widget.barPadding,height: widget.toolbarHeight,alignment: Alignment.center,child: Row(mainAxisAlignment: MainAxisAlignment.center,crossAxisAlignment: CrossAxisAlignment.center,children: [Container(height: widget.toolbarHeight,child: leadingWidget,),Expanded(child: Container(alignment: Alignment.center,height: widget.toolbarHeight,child: centerWidget,),),Container(height: widget.toolbarHeight,child: trailingWidget,),],),),)],),),),);}
}

实现扫一扫界面

class QrScanPage extends StatefulWidget {const QrScanPage({Key? key, this.arguments}) : super(key: key);final Object? arguments;@overrideState<QrScanPage> createState() => _QrScanPageState();
}class _QrScanPageState extends State<QrScanPage> {ScanController scanController = ScanController();String qrcode = 'Unknown';bool torchOn = false;@overridevoid initState() {// TODO: implement initStatesuper.initState();}@overridevoid dispose() {// TODO: implement disposescanController.pause();super.dispose();}void changedTorchMode() {scanController.toggleTorchMode();if (torchOn == true) {torchOn = false;} else {torchOn = true;}setState(() {});}void refreshScan() {scanController.resume();}// controller.resume();// controller.pause();// String result = await Scan.parse(imagePath);@overrideWidget build(BuildContext context) {return Scaffold(body: Stack(children: [buildQrScanView(context),Positioned(child: buildAppBar(context),),],),);}Widget buildQrScanView(BuildContext context) {double width = MediaQuery.of(context).size.width;double height = MediaQuery.of(context).size.height;double scanW = width * 0.75;double scanMY = (height - scanW) / 2.0 + scanW + 15.0;return Container(alignment: Alignment.center,child: Stack(alignment: Alignment.center,children: [ScanView(controller: scanController,// custom scan area, if set to 1.0, will scan full areascanAreaScale: 0.75,scanLineColor: Colors.green.shade400,onCapture: (data) {// do somethingLoggerManager().debug("onCapture:${data}");openQrScanWebPage(data);},),Positioned(top: scanMY,child: buildOption(context, scanMY),),],),);}Widget buildAppBar(BuildContext context) {return QrScanAppBar(toolbarHeight: 44.0,backgroundColor: Colors.transparent,padding: EdgeInsets.symmetric(horizontal: 10.0),barPadding: EdgeInsets.symmetric(vertical: 4.0),leadingWidget: Container(alignment: Alignment.center,child: QrscanButton(bgColor: ColorUtil.hexColor(0xA9A9A9),bgHighlightedColor: ColorUtil.hexColor(0xf0f0f0),borderColor: Colors.transparent,onPressed: () {navigatorBack();},borderRadius: 18.0,height: 36.0,width: 36.0,child: ImageHelper.wrapAssetAtImages("icons/ic_scan_navback.png",width: 36.0,height: 36.0,fit: BoxFit.fill,),),),centerWidget: Text(S.of(context).qrScan,textAlign: TextAlign.center,softWrap: true,style: TextStyle(fontSize: 17,color: ColorUtil.hexColor(0xffffff),fontWeight: FontWeight.w600,fontStyle: FontStyle.normal,decoration: TextDecoration.none,),),trailingWidget: Container(width: 32.0,height: 32.0,),);}Widget buildOption(BuildContext context, double originY) {return Container(height: ScreenUtil().screenHeight - originY,width: ScreenUtil().screenWidth,child: Column(mainAxisAlignment: MainAxisAlignment.center,crossAxisAlignment: CrossAxisAlignment.center,children: [Container(width: 300.0,child: Text(S.of(context).qrScanBottomTip,textAlign: TextAlign.center,softWrap: true,style: TextStyle(fontSize: 15,fontWeight: FontWeight.w500,fontStyle: FontStyle.normal,color: Colors.white,decoration: TextDecoration.none,),),),SizedBox(height: 25.0,),buildButtons(context),Expanded(child: Container(),),],),);}Widget buildButtons(BuildContext context) {return Row(mainAxisAlignment: MainAxisAlignment.center,crossAxisAlignment: CrossAxisAlignment.center,children: [Padding(padding: EdgeInsets.symmetric(horizontal: 20.0),child: QrscanButton(bgColor: ColorUtil.hexColor(0x35fb99),bgHighlightedColor: Colors.green.shade400,onPressed: () {changedTorchMode();},width: 100.0,height: 50.0,borderRadius: 25.0,child: Text((torchOn? S.of(context).qrScanTorchOff: S.of(context).qrScanTorchOn),textAlign: TextAlign.center,softWrap: true,style: TextStyle(fontSize: 14,color: ColorUtil.hexColor(0xffffff),fontWeight: FontWeight.w600,fontStyle: FontStyle.normal,decoration: TextDecoration.none,),),),),Padding(padding: EdgeInsets.symmetric(horizontal: 20.0),child: QrscanButton(bgColor: ColorUtil.hexColor(0x35fb99),bgHighlightedColor: Colors.green.shade400,onPressed: () {refreshScan();},width: 100.0,height: 50.0,borderRadius: 25.0,child: Text(S.of(context).qrScanRefresh,textAlign: TextAlign.center,softWrap: true,style: TextStyle(fontSize: 14,color: ColorUtil.hexColor(0xffffff),fontWeight: FontWeight.w600,fontStyle: FontStyle.normal,decoration: TextDecoration.none,),),),),],);}void navigatorBack() {NavigatorPageRouter.pop();}void openQrScanWebPage(String data) {Map<String, dynamic> args = {};args["url"] = data;/// true保留跳转的当前栈   false 不保留NavigatorPageRouter.pushReplacementNamed(RouterName.web,arguments: args,);}
}

三、小结

flutter开发实战-flutter二维码扫一扫功能实现，要使用到摄像头的原生的功能，使用的是插件：scan，实现自定义Appbar。

学习记录，每天不停进步。