Flutter [image_picke] 调用相机拍照丶拍摄，相册图片丶视频选择。

PUb包地址：https://pub.dev/packages/image_picker

介绍：Flutter 插件，用于从 Android 和 iOS 图像库中选择图像，并使用相机拍摄新照片。

import 'dart:io';

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

main() {
  runApp(mater());
}

class mater extends StatefulWidget {
  const mater({Key? key}) : super(key: key);

  @override
  State<mater> createState() => _materState();
}

class _materState extends State<mater> {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: ImagePickerPage(),
    );
  }
}

class ImagePickerPage extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return _ImagePickerState();
  }
}

class _ImagePickerState extends State<ImagePickerPage> {
  var _imgPath;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text("ImagePicker"),
        ),
        body: SingleChildScrollView(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: <Widget>[
              _ImageView(_imgPath),
              RaisedButton(
                onPressed: _takePhoto,
                child: Text("拍照"),
              ),
              RaisedButton(
                onPressed: _openGallery,
                child: Text("单选照片"),
              ),
              RaisedButton(
                onPressed: _openGalleryall,
                child: Text("多选照片"),
              ),
              RaisedButton(
                onPressed: _shoot,
                child: Text("拍摄视频"),
              ),
              RaisedButton(
                onPressed: _openmp4,
                child: Text("单选视频"),
              ),
            ],
          ),
        ));
  }

/*图片控件*/
  Widget _ImageView(imgPath) {
    if (imgPath == null) {
      return Center(
        child: Text("请选择图片或拍照"),
      );
    } else {
      return Image.file(
        File(imgPath),
      );
    }
  }

  // source 类型=>
  // /// 指定拾取图像的来源。
  // enum ImageSource {
  // /// 打开设备相机，让用户拍摄一张新照片。
  // camera,
  // /// 打开用户的照片库。
  // gallery,
  // }

/*拍照*/
  _takePhoto() async {
    var image = await ImagePicker.platform
        .pickImage(source: ImageSource.camera, maxWidth: 400);
   setState(() {
   _imgPath = image?.path;
   });
    print(image?.path); //图片路径
  }

/*单选图片相册*/
  _openGallery() async {
    var image =
        await ImagePicker.platform.pickImage(source: ImageSource.gallery);
     setState(() {
     _imgPath = image?.path;
     });
    print(image?.path); //图片路径
  }

/*多选图片相册*/
  _openGalleryall() async {
    var image = await ImagePicker.platform.pickMultiImage();
    print(image); //一个list
  }

  /**
   * 下面是视频操作
   */
  /*拍摄视频*/
  _shoot() async {
    var image =
        await ImagePicker.platform.pickVideo(source: ImageSource.camera);
    print(image?.path); //一个list
  }

  /*选择视频*/
  _openmp4() async {
    var image =
        await ImagePicker.platform.pickVideo(source: ImageSource.gallery);
    print(image?.path); //一个list
  }
}