Flutter 在图库视图网格中渲染应用程序中拍摄的照片_Flutter

Flutter 在图库视图网格中渲染应用程序中拍摄的照片

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Flutter 在图库视图网格中渲染应用程序中拍摄的照片,flutter,Flutter,我正在创建一个应用程序，当没有用户生成的内容时，它会显示一条消息，但当用户拍照时，它会在网格画廊视图中显示照片我已经在使用条件逻辑来实现这一点，但是，当我按下相机按钮时，相机会显示并拍摄照片，但是照片不会以所需的格式返回主页下面有一个关于我试图实现的流程的屏幕截图，供您参考。希望有人能帮忙纠正我有下面完整的生殖代码，可以复制正在发生的事情。基于我所拥有的、我的研究和知识，这应该已经实现了，因为我正在通过相机页面中的以下内容将拍摄的照片推回到主页 Navigator.push(

我正在创建一个应用程序，当没有用户生成的内容时，它会显示一条消息，但当用户拍照时，它会在网格画廊视图中显示照片

我已经在使用条件逻辑来实现这一点，但是，当我按下相机按钮时，相机会显示并拍摄照片，但是照片不会以所需的格式返回主页

下面有一个关于我试图实现的流程的屏幕截图，供您参考。希望有人能帮忙纠正

我有下面完整的生殖代码，可以复制正在发生的事情。基于我所拥有的、我的研究和知识，这应该已经实现了，因为我正在通过相机页面中的以下内容将拍摄的照片推回到主页

Navigator.push(
        context,
        MaterialPageRoute(
            builder: (context) => Homepage_1(
                  imgPath: path,
                )),

这是相机页面的代码

import 'package:camera/camera.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:path/path.dart';
import 'package:path_provider/path_provider.dart';
import 'package:image_picker/image_picker.dart';
import 'preview_screen.dart';

class Camera extends StatefulWidget {
  @override
  _CameraScreenState createState() => _CameraScreenState();
}

class _CameraScreenState extends State {
  CameraController controller;
  List cameras;
  int selectedCameraIndex;
  String imgPath;
  var image; //
  List imageArray = []; //

  _openGallery() async {
    image = await ImagePicker.pickImage(source: ImageSource.camera);
    imageArray.add(image);
    setState(() {
      imageArray;
    });
  }

  @override
  void initState() {
    super.initState();
    availableCameras().then((availableCameras) {
      cameras = availableCameras;

      if (cameras.length > 0) {
        setState(() {
          selectedCameraIndex = 0;
        });
        _initCameraController(cameras[selectedCameraIndex]).then((void v) {});
      } else {
        print('No camera available');
      }
    }).catchError((err) {
      print('Error :${err.code}Error message : ${err.message}');
    });
  }

  Future _initCameraController(CameraDescription cameraDescription) async {
    if (controller != null) {
      await controller.dispose();
    }
    controller = CameraController(cameraDescription, ResolutionPreset.high);

    controller.addListener(() {
      if (mounted) {
        setState(() {});
      }

      if (controller.value.hasError) {
        print('Camera error ${controller.value.errorDescription}');
      }
    });

    try {
      await controller.initialize();
    } on CameraException catch (e) {
      _showCameraException(e);
    }
    if (mounted) {
      setState(() {});
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        child: SafeArea(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: <Widget>[
              Expanded(
                flex: 1,
                child: _cameraPreviewWidget(),
              ),
              Align(
                alignment: Alignment.bottomCenter,
                child: Container(
                  height: 120,
                  width: double.infinity,
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.start,
                    children: <Widget>[
                      _cameraToggleRowWidget(),
                      _cameraControlWidget(context),
                      Spacer()
                    ],
                  ),
                ),
              )
            ],
          ),
        ),
      ),
    );
  }

  /// Display Camera preview.
  Widget _cameraPreviewWidget() {
    if (controller == null || !controller.value.isInitialized) {
      return const Text(
        'Loading',
        style: TextStyle(
          color: Colors.white,
          fontSize: 20.0,
          fontWeight: FontWeight.w900,
        ),
      );
    }

    return AspectRatio(
      aspectRatio: controller.value.aspectRatio,
      child: CameraPreview(controller),
    );
  }

  /// Display the control bar with buttons to take pictures
  Widget _cameraControlWidget(context) {
    return Expanded(
      child: Align(
        alignment: Alignment.center,
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          mainAxisSize: MainAxisSize.max,
          children: <Widget>[
            FloatingActionButton(
              child: Icon(
                Icons.camera,
                color: Colors.black,
              ),
              backgroundColor: Colors.white,
              onPressed: () {
                _openGallery();
              },
            )
          ],
        ),
      ),
    );
  }

  /// Display a row of toggle to select the camera (or a message if no camera is available).
  Widget _cameraToggleRowWidget() {
    if (cameras == null || cameras.isEmpty) {
      return Spacer();
    }
    CameraDescription selectedCamera = cameras[selectedCameraIndex];
    CameraLensDirection lensDirection = selectedCamera.lensDirection;

    return Expanded(
      child: Align(
        alignment: Alignment.centerLeft,
        child: FlatButton.icon(
          onPressed: _onSwitchCamera,
          icon: Icon(
            _getCameraLensIcon(lensDirection),
            color: Colors.white,
            size: 24,
          ),
          label: Text(
            '${lensDirection.toString().substring(lensDirection.toString().indexOf('.') + 1).toUpperCase()}',
            style: TextStyle(color: Colors.white, fontWeight: FontWeight.w500),
          ),
        ),
      ),
    );
  }

  IconData _getCameraLensIcon(CameraLensDirection direction) {
    switch (direction) {
      case CameraLensDirection.back:
        return CupertinoIcons.switch_camera;
      case CameraLensDirection.front:
        return CupertinoIcons.switch_camera_solid;
      case CameraLensDirection.external:
        return Icons.camera;
      default:
        return Icons.device_unknown;
    }
  }

  void _showCameraException(CameraException e) {
    String errorText = 'Error:${e.code}\nError message : ${e.description}';
    print(errorText);
  }

  void _onCapturePressed(context) async {
    try {
      final path =
          join((await getTemporaryDirectory()).path, '${DateTime.now()}.png');
      await controller.takePicture();

      Navigator.push(
        context,
        MaterialPageRoute(
            builder: (context) => Homepage_1(
                  imgPath: path,
                )),
      );
    } catch (e) {
      _showCameraException(e);
    }
  }

  void _onSwitchCamera() {
    selectedCameraIndex =
        selectedCameraIndex < cameras.length - 1 ? selectedCameraIndex + 1 : 0;
    CameraDescription selectedCamera = cameras[selectedCameraIndex];
    _initCameraController(selectedCamera);
  }
}

下面是包含条件逻辑的代码本身

    import 'package:flutter/material.dart';
    import 'package:image_picker/image_picker.dart';
    
    
    class Homepage_1 extends StatefulWidget {

  //specify a FINAL variable
  final imgPath;

  //this is the constructor which allows you to send it
  const Homepage_1({this.imgPath});

      @override
      _Homepage_1State createState() => _Homepage_1State();
    }
    
    class _Homepage_1State extends State<Homepage_1> {
      var image;
      List imageArray = [];
    
        _openGallery() async {
        image = await ImagePicker.pickImage(source: ImageSource.camera);
        imageArray.add(image);
        setState(() {
          imageArray;
        });
      }
    
    
      @override
      Widget build(BuildContext context) {
        print(imageArray);
        return Scaffold(
            resizeToAvoidBottomInset: false,
            resizeToAvoidBottomPadding: false,
            backgroundColor: Colors.white,
            body: Column(crossAxisAlignment: CrossAxisAlignment.stretch, children: [
              Padding(
                padding:
                    const EdgeInsets.only(top: 100, left: 40, right: 0, bottom: 0),
                child:
                    Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
                  Text(
                    'Title',
                    style: TextStyle(
                      fontSize: 60,
                      fontFamily: 'Avenir',
                      fontWeight: FontWeight.w900,
                    ),
                  ),
                  Container(
                      margin:
                          EdgeInsets.only(top: 0, left: 0, right: 70, bottom: 0),
                      child: imageArray.isEmpty
                          ? Column(children: [
                              Text(
                                'Yikes! You have no photos',
                                style: TextStyle(
                                  fontSize: 19,
                                  fontFamily: 'Avenir',
                                  fontWeight: FontWeight.w900,
                                ),
                              ),
                              Text(
                                'Click the circular button below.',
                                style: TextStyle(
                                  fontSize: 15,
                                  fontFamily: 'Avenir',
                                  fontWeight: FontWeight.w500,
                                ),
                              ),
                            ])
                          : GridView.count(
                              crossAxisCount: 2,
                              children: List.generate(imageArray.length, (index) {
                                var img = imageArray[index];
                                return Container(child: Image.file(this.widget.imgPath));
                              })))
                ]),
              )
            ]));
      }
    }

这里也是我的底部导航，供您参考

import 'package:flutter/material.dart';
import 'Camera.dart';
import 'Homepage_1.dart';
import 'Settings.dart';

class Home extends StatefulWidget {
  @override
  _HomeState createState() => _HomeState();
}

class _HomeState extends State<Home> {
// properties

  int currentTab = 0;
  final List<Widget> screens = [
    Settings(),
    Camera(),
    Homepage_1(),
  ];

  Widget currentScreen = Homepage_1();

  final PageStorageBucket bucket = PageStorageBucket();

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: PageStorage(
        child: currentScreen,
        bucket: bucket,
      ),
      floatingActionButton: ConstrainedBox(
        constraints: BoxConstraints.tightFor(width: 80, height: 80),
        child: ElevatedButton(
          child: Icon(Icons.center_focus_strong, size: 39),
          onPressed: () {
            Navigator.push(
                context, MaterialPageRoute(builder: (context) => Camera()));
          },
          style: ElevatedButton.styleFrom(
              shape: CircleBorder(), primary: Color(0xff33333D)),
        ),
      ),
      floatingActionButtonLocation: FloatingActionButtonLocation.centerDocked,
      bottomNavigationBar: BottomAppBar(
          child: Container(
        height: 60,
        child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: <Widget>[
              Row(children: <Widget>[
                MaterialButton(
                  minWidth: 150,
                  onPressed: () {
                    setState(
                      () {
                        currentScreen = Homepage_1();
                        currentTab = 0;
                      },
                    );
                  },
                  child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: <Widget>[
                        ImageIcon(
                          AssetImage("assets/Home_Selected.png"),
                          color: currentTab == 0
                              ? Color(0xff33333D)
                              : Color(0xffC6CBD1),
                        ),
                      ]),
                )
              ]),
              Row(children: <Widget>[
                MaterialButton(
                  minWidth: 150,
                  onPressed: () {
                    setState(
                      () {
                        currentScreen = Settings();
                        currentTab = 1;
                      },
                    );
                  },
                  child: Column(
                      mainAxisAlignment: MainAxisAlignment.center,
                      children: <Widget>[
                        ImageIcon(
                          AssetImage("assets/Settings.png"),
                          color: currentTab == 1
                              ? Color(0xff33333D)
                              : Color(0xffC6CBD1),
                        ),
                      ]),
                )
              ])
            ]),
      )),
    );
  }
}

您没有以正确的方式将其发送回主页。主页_1小部件中没有imgPath变量，您必须在以下步骤之前添加它：

class Homepage_1 extends StatefulWidget {

   //specify a FINAL variable
   final imgPath;
   
   //this is the constructor which allows you to send it
   const Homepage_1({this.imgPath});
   
   @override
   _Homepage_1State createState() => _Homepage_1State();

}

现在，您可以访问State类中的imgPath变量，如下所示：

this.widget.imgPath

按如下方式推至主屏幕_1：

Navigator.push(
        context,
        MaterialPageRoute(
            builder: (context) => Homepage_1(
                  imgPath: path,
                )),

您没有以正确的方式将其发送回主页。主页_1小部件中没有imgPath变量，您必须在以下步骤之前添加它：

class Homepage_1 extends StatefulWidget {

   //specify a FINAL variable
   final imgPath;
   
   //this is the constructor which allows you to send it
   const Homepage_1({this.imgPath});
   
   @override
   _Homepage_1State createState() => _Homepage_1State();

}

现在，您可以访问State类中的imgPath变量，如下所示：

this.widget.imgPath

按如下方式推至主屏幕_1：

Navigator.push(
        context,
        MaterialPageRoute(
            builder: (context) => Homepage_1(
                  imgPath: path,
                )),

我假设您仍在测试camera库，并尝试将图像从类camera传递到类Homepage_1，所以我只关注数据传递部分。您犯了一些小错误：

类摄像机

我假设您想使用_onCapturePressednot _openGallery将图像路径发送到主页。实际文件路径是从takePicture返回的

final xFile = await controller.takePicture();
...
Navigator.push(
   ...
   imgPath: xFile.path,
...

班级主页(1)

使用imageArray构建网格，但不向其中添加任何文件/路径

@override
Widget build(BuildContext context) {
  if (widget.imgPath != null) {
    imageArray.add(File(widget.imgPath));
  }

  ...
    child: GridView.count(
      crossAxisCount: 2,
      children: List.generate(
        imageArray.length,
        (index) {
          var img = imageArray[index];
          return Container(child: Image.file(img));
        },
      ),
    ),

那么它现在应该可以工作了

注意:

Library ImagePicker已打开手机上的本机相机/多媒体资料，Library camera用于在应用程序中自定义您的相机，不建议同时使用它们。因为类摄像头和类主页_1不在使用Navigator.push的屏幕的同一级别上，所以可以将摄像头屏幕堆叠在主页_1上。更新主页_1的最佳方法是在相机中使用Navigator.pop并将图像路径带回主页_1。你可以查看参考资料

我假设您仍在测试camera库，并尝试将图像从类camera传递到类Homepage_1，所以我只关注数据传递部分。您犯了一些小错误：

类摄像机

我假设您想使用_onCapturePressednot _openGallery将图像路径发送到主页。实际文件路径是从takePicture返回的

final xFile = await controller.takePicture();
...
Navigator.push(
   ...
   imgPath: xFile.path,
...

班级主页(1)

使用imageArray构建网格，但不向其中添加任何文件/路径

@override
Widget build(BuildContext context) {
  if (widget.imgPath != null) {
    imageArray.add(File(widget.imgPath));
  }

  ...
    child: GridView.count(
      crossAxisCount: 2,
      children: List.generate(
        imageArray.length,
        (index) {
          var img = imageArray[index];
          return Container(child: Image.file(img));
        },
      ),
    ),

那么它现在应该可以工作了

注意:

我对你的文件做了一些更改。请调查一下。虽然您可以直接在主页中使用ImagePicker.pickImage，但我按照您的代码解决了它。我使用了回调函数将camera.dart中的图像输入到您的主页。有关回调函数的更多了解，请参考以下链接

然后是相机文件

import 'package:camera/camera.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';

class Camera extends StatefulWidget {
  Function setData;
  Camera({Key key,this.setData}):super(key: key);

  @override
  _CameraScreenState createState() => _CameraScreenState();
}

class _CameraScreenState extends State<Camera> {
  CameraController controller;
  List cameras;
  int selectedCameraIndex;
  String imgPath;
  var image;

  Future _openGallery() async {
    image = await ImagePicker.pickImage(source: ImageSource.camera);
      if(widget.setData!=null) {
        widget.setData(image);
      }
  }

  @override
  void initState() {
    super.initState();
    availableCameras().then((availableCameras) {
      cameras = availableCameras;

      if (cameras.length > 0) {
        setState(() {
          selectedCameraIndex = 0;
        });
        _initCameraController(cameras[selectedCameraIndex]).then((void v) {});
      } else {
        print('No camera available');
      }
    }).catchError((err) {
      print('Error :${err.code}Error message : ${err.message}');
    });
  }

  Future _initCameraController(CameraDescription cameraDescription) async {
    if (controller != null) {
      await controller.dispose();
    }
    controller = CameraController(cameraDescription, ResolutionPreset.high);

    controller.addListener(() {
      if (mounted) {
        setState(() {});
      }

      if (controller.value.hasError) {
        print('Camera error ${controller.value.errorDescription}');
      }
    });

    try {
      await controller.initialize();
    } on CameraException catch (e) {
      _showCameraException(e);
    }
    if (mounted) {
      setState(() {});
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        child: SafeArea(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: <Widget>[
              Expanded(
                flex: 1,
                child: _cameraPreviewWidget(),
              ),
              Align(
                alignment: Alignment.bottomCenter,
                child: Container(
                  height: 120,
                  width: double.infinity,
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.start,
                    children: <Widget>[
                      _cameraToggleRowWidget(),
                      _cameraControlWidget(context),
                      Spacer()
                    ],
                  ),
                ),
              )
            ],
          ),
        ),
      ),
    );
  }

  /// Display Camera preview.
  Widget _cameraPreviewWidget() {
    if (controller == null || !controller.value.isInitialized) {
      return const Text(
        'Loading',
        style: TextStyle(
          color: Colors.white,
          fontSize: 20.0,
          fontWeight: FontWeight.w900,
        ),
      );
    }

    return AspectRatio(
      aspectRatio: controller.value.aspectRatio,
      child: CameraPreview(controller),
    );
  }

  /// Display the control bar with buttons to take pictures
  Widget _cameraControlWidget(context) {
    return Expanded(
      child: Align(
        alignment: Alignment.center,
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          mainAxisSize: MainAxisSize.max,
          children: <Widget>[
            FloatingActionButton(
              child: Icon(
                Icons.camera,
                color: Colors.black,
              ),
              backgroundColor: Colors.white,
              onPressed: () {
                // getImage();
                _openGallery();
                Navigator.pop(context);
              },
            )
          ],
        ),
      ),
    );
  }

  /// Display a row of toggle to select the camera (or a message if no camera is available).
  Widget _cameraToggleRowWidget() {
    if (cameras == null || cameras.isEmpty) {
      return Spacer();
    }
    CameraDescription selectedCamera = cameras[selectedCameraIndex];
    CameraLensDirection lensDirection = selectedCamera.lensDirection;

    return Expanded(
      child: Align(
        alignment: Alignment.centerLeft,
        child: FlatButton.icon(
          onPressed: _onSwitchCamera,
          icon: Icon(
            _getCameraLensIcon(lensDirection),
            color: Colors.white,
            size: 24,
          ),
          label: Text(
            '${lensDirection.toString().substring(lensDirection.toString().indexOf('.') + 1).toUpperCase()}',
            style: TextStyle(color: Colors.white, fontWeight: FontWeight.w500),
          ),
        ),
      ),
    );
  }

  IconData _getCameraLensIcon(CameraLensDirection direction) {
    switch (direction) {
      case CameraLensDirection.back:
        return CupertinoIcons.switch_camera;
      case CameraLensDirection.front:
        return CupertinoIcons.switch_camera_solid;
      case CameraLensDirection.external:
        return Icons.camera;
      default:
        return Icons.device_unknown;
    }
  }

  void _showCameraException(CameraException e) {
    String errorText = 'Error:${e.code}\nError message : ${e.description}';
    print(errorText);
  }


  void _onSwitchCamera() {
    selectedCameraIndex =
    selectedCameraIndex < cameras.length - 1 ? selectedCameraIndex + 1 : 0;
    CameraDescription selectedCamera = cameras[selectedCameraIndex];
    _initCameraController(selectedCamera);
  }
}

主页_1显示图像

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

class Homepage_1 extends StatefulWidget {
  final List<File> imageArray;
  Homepage_1({Key key, this.imageArray}) : super(key: key);

  @override
  _Homepage_1State createState() => _Homepage_1State();
}

class _Homepage_1State extends State<Homepage_1> {
  var image;

  @override
  void initState() {
    // TODO: implement initState
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        resizeToAvoidBottomInset: false,
        resizeToAvoidBottomPadding: false,
        backgroundColor: Colors.white,
        body: Column(crossAxisAlignment: CrossAxisAlignment.stretch, children: [
          Padding(
            padding:
                const EdgeInsets.only(top: 100, left: 40, right: 0, bottom: 0),
            child:
                Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
              Text(
                'Title',
                style: TextStyle(
                  fontSize: 60,
                  fontFamily: 'Avenir',
                  fontWeight: FontWeight.w900,
                ),
              ),
              Container(
                  margin:
                      EdgeInsets.only(top: 0, left: 0, right: 70, bottom: 0),
                  child: widget.imageArray.isEmpty
                      ? Column(children: [
                          Text(
                            'Yikes! You have no photos',
                            style: TextStyle(
                              fontSize: 19,
                              fontFamily: 'Avenir',
                              fontWeight: FontWeight.w900,
                            ),
                          ),
                          Text(
                            'Click the circular button below.',
                            style: TextStyle(
                              fontSize: 15,
                              fontFamily: 'Avenir',
                              fontWeight: FontWeight.w500,
                            ),
                          ),
                        ])
                      :
                  GridView.count(
                    shrinkWrap: true,
                          crossAxisCount: 2,
                          childAspectRatio: 1.0,
                          padding: const EdgeInsets.all(4.0),
                          children:
                              List.generate(widget.imageArray.length, (index) {
                            return Container(
                                child: Image.file(widget.imageArray[index]));
                          })))
            ]),
          )
        ]));
  }
}

我希望这能解决你的问题，因为我为此花了很多时间。享受：

然后是相机文件

import 'package:camera/camera.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';

class Camera extends StatefulWidget {
  Function setData;
  Camera({Key key,this.setData}):super(key: key);

  @override
  _CameraScreenState createState() => _CameraScreenState();
}

class _CameraScreenState extends State<Camera> {
  CameraController controller;
  List cameras;
  int selectedCameraIndex;
  String imgPath;
  var image;

  Future _openGallery() async {
    image = await ImagePicker.pickImage(source: ImageSource.camera);
      if(widget.setData!=null) {
        widget.setData(image);
      }
  }

  @override
  void initState() {
    super.initState();
    availableCameras().then((availableCameras) {
      cameras = availableCameras;

      if (cameras.length > 0) {
        setState(() {
          selectedCameraIndex = 0;
        });
        _initCameraController(cameras[selectedCameraIndex]).then((void v) {});
      } else {
        print('No camera available');
      }
    }).catchError((err) {
      print('Error :${err.code}Error message : ${err.message}');
    });
  }

  Future _initCameraController(CameraDescription cameraDescription) async {
    if (controller != null) {
      await controller.dispose();
    }
    controller = CameraController(cameraDescription, ResolutionPreset.high);

    controller.addListener(() {
      if (mounted) {
        setState(() {});
      }

      if (controller.value.hasError) {
        print('Camera error ${controller.value.errorDescription}');
      }
    });

    try {
      await controller.initialize();
    } on CameraException catch (e) {
      _showCameraException(e);
    }
    if (mounted) {
      setState(() {});
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Container(
        child: SafeArea(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: <Widget>[
              Expanded(
                flex: 1,
                child: _cameraPreviewWidget(),
              ),
              Align(
                alignment: Alignment.bottomCenter,
                child: Container(
                  height: 120,
                  width: double.infinity,
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.start,
                    children: <Widget>[
                      _cameraToggleRowWidget(),
                      _cameraControlWidget(context),
                      Spacer()
                    ],
                  ),
                ),
              )
            ],
          ),
        ),
      ),
    );
  }

  /// Display Camera preview.
  Widget _cameraPreviewWidget() {
    if (controller == null || !controller.value.isInitialized) {
      return const Text(
        'Loading',
        style: TextStyle(
          color: Colors.white,
          fontSize: 20.0,
          fontWeight: FontWeight.w900,
        ),
      );
    }

    return AspectRatio(
      aspectRatio: controller.value.aspectRatio,
      child: CameraPreview(controller),
    );
  }

  /// Display the control bar with buttons to take pictures
  Widget _cameraControlWidget(context) {
    return Expanded(
      child: Align(
        alignment: Alignment.center,
        child: Row(
          mainAxisAlignment: MainAxisAlignment.spaceEvenly,
          mainAxisSize: MainAxisSize.max,
          children: <Widget>[
            FloatingActionButton(
              child: Icon(
                Icons.camera,
                color: Colors.black,
              ),
              backgroundColor: Colors.white,
              onPressed: () {
                // getImage();
                _openGallery();
                Navigator.pop(context);
              },
            )
          ],
        ),
      ),
    );
  }

  /// Display a row of toggle to select the camera (or a message if no camera is available).
  Widget _cameraToggleRowWidget() {
    if (cameras == null || cameras.isEmpty) {
      return Spacer();
    }
    CameraDescription selectedCamera = cameras[selectedCameraIndex];
    CameraLensDirection lensDirection = selectedCamera.lensDirection;

    return Expanded(
      child: Align(
        alignment: Alignment.centerLeft,
        child: FlatButton.icon(
          onPressed: _onSwitchCamera,
          icon: Icon(
            _getCameraLensIcon(lensDirection),
            color: Colors.white,
            size: 24,
          ),
          label: Text(
            '${lensDirection.toString().substring(lensDirection.toString().indexOf('.') + 1).toUpperCase()}',
            style: TextStyle(color: Colors.white, fontWeight: FontWeight.w500),
          ),
        ),
      ),
    );
  }

  IconData _getCameraLensIcon(CameraLensDirection direction) {
    switch (direction) {
      case CameraLensDirection.back:
        return CupertinoIcons.switch_camera;
      case CameraLensDirection.front:
        return CupertinoIcons.switch_camera_solid;
      case CameraLensDirection.external:
        return Icons.camera;
      default:
        return Icons.device_unknown;
    }
  }

  void _showCameraException(CameraException e) {
    String errorText = 'Error:${e.code}\nError message : ${e.description}';
    print(errorText);
  }


  void _onSwitchCamera() {
    selectedCameraIndex =
    selectedCameraIndex < cameras.length - 1 ? selectedCameraIndex + 1 : 0;
    CameraDescription selectedCamera = cameras[selectedCameraIndex];
    _initCameraController(selectedCamera);
  }
}

主页_1显示图像

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

class Homepage_1 extends StatefulWidget {
  final List<File> imageArray;
  Homepage_1({Key key, this.imageArray}) : super(key: key);

  @override
  _Homepage_1State createState() => _Homepage_1State();
}

class _Homepage_1State extends State<Homepage_1> {
  var image;

  @override
  void initState() {
    // TODO: implement initState
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        resizeToAvoidBottomInset: false,
        resizeToAvoidBottomPadding: false,
        backgroundColor: Colors.white,
        body: Column(crossAxisAlignment: CrossAxisAlignment.stretch, children: [
          Padding(
            padding:
                const EdgeInsets.only(top: 100, left: 40, right: 0, bottom: 0),
            child:
                Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
              Text(
                'Title',
                style: TextStyle(
                  fontSize: 60,
                  fontFamily: 'Avenir',
                  fontWeight: FontWeight.w900,
                ),
              ),
              Container(
                  margin:
                      EdgeInsets.only(top: 0, left: 0, right: 70, bottom: 0),
                  child: widget.imageArray.isEmpty
                      ? Column(children: [
                          Text(
                            'Yikes! You have no photos',
                            style: TextStyle(
                              fontSize: 19,
                              fontFamily: 'Avenir',
                              fontWeight: FontWeight.w900,
                            ),
                          ),
                          Text(
                            'Click the circular button below.',
                            style: TextStyle(
                              fontSize: 15,
                              fontFamily: 'Avenir',
                              fontWeight: FontWeight.w500,
                            ),
                          ),
                        ])
                      :
                  GridView.count(
                    shrinkWrap: true,
                          crossAxisCount: 2,
                          childAspectRatio: 1.0,
                          padding: const EdgeInsets.all(4.0),
                          children:
                              List.generate(widget.imageArray.length, (index) {
                            return Container(
                                child: Image.file(widget.imageArray[index]));
                          })))
            ]),
          )
        ]));
  }
}

我希望这能解决你的问题，因为我为此花了很多时间。享受：

刚刚尝试过，但仍然没有任何内容呈现到主页上。我编辑了代码以包含您的编辑。。。你能再看看吗？在这里不知所措…只是尝试了一下，但仍然没有任何东西呈现到主页上。我编辑了代码以包含您的编辑。。。你能再看看吗？在这里不知所措…只是一个建议，尽量保持正确的命名惯例。从您要将图像发送到何处以及图像应显示在何处，这让人感到困惑。建议您尽量保持正确的命名约定。从何而来令人困惑 e您要发送图像，以及图像应显示的位置。