flutter项目中 advance_image_picker 组件使用

一、说明

Advance_image_picker 是flutter 插件，用于从Android 和 ios 图像库中选择多张图片，使用相机拍摄新照片，并对其进行编辑。

下图为最终效果：

这里有个bug ，在连续多测按 旋转摄像头时，程序会出现卡顿的情况。

二、使用方式

IOS ：
将这些设置添加到 ios/Runner/Info.plist

<key>NSCameraUsageDescription</key>
<string>Can I use the camera please?</string>
<key>NSMicrophoneUsageDescription</key>
<string>Can I use the mic please?</string>
<key>NSPhotoLibraryUsageDescription</key>
<string>App need your agree, can visit your album</string>

Android ：
在您的android/app/build.gradle文件中将最低 Android sdk 版本更改为 21（或更高）。
将活动和使用权限添加到您的AndroidManifest.xml，就像下一步一样。

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="vn.weta.freemarimagepickerexample">

    <application
        android:name="io.flutter.app.FlutterApplication"
        android:label="freemarimagepicker_example"
        android:requestLegacyExternalStorage="true"
        android:icon="@mipmap/ic_launcher">
        <activity
            android:name="com.yalantis.ucrop.UCropActivity"
            android:screenOrientation="portrait"
            android:theme="@style/Theme.AppCompat.Light.NoActionBar"/>
    </application>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.CAMERA" />
</manifest>

添加到 pubspec
flutter项目的 pubspec.yaml 中添加依赖：

dependencies:
  advance_image_picker: $latest_version

三、项目代码

最近自己动手做的项目是通过Getx 开发。插件测试代码分为 view 端代码和 controller 端代码，这里一并贴出

view 端代码：

class ImagePickerScreen extends GetView<ImagePickerController> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Obx(
          () => Text(
            controller.pageName.value,
            style: TextStyle(
              color: Theme.of(context).appBarTheme.titleTextStyle!.color,
            ),
          ),
        ),
        centerTitle: true,
      ),
      body: _buildBody(context),
    );
  }

  Widget _buildBody(BuildContext context) {
    return SingleChildScrollView(
      child: SafeArea(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.start,
          children: [
            Container(
              child: ElevatedButton(
                onPressed: () {
                  controller.getImages();
                },
                child: Text('上传图标'),
              ),
            ),
            _buildImages(context),
          ],
        ),
      ),
    );
  }

  Widget _buildImages(BuildContext context) {
    return Obx(
      () => GridView.builder(
        itemCount: controller.imgObjs.length,
        shrinkWrap: true,
        gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
            crossAxisCount: 4, mainAxisSpacing: 2),
        itemBuilder: (BuildContext context, int index) {
          return Padding(
            padding: EdgeInsets.all(2),
            child: Image.file(
              File(controller.imgObjs[index]),
              height: 80,
              fit: BoxFit.cover,
            ),
          );
        },
      ),
    );
  }
}

contoller 部分代码：
ApiRepository 用于网络请求 ，这里通过构造器依赖注入。由于测试过程中，没有用到网络请求，这部分省略。

class ImagePickerController extends GetxController
    with GetSingleTickerProviderStateMixin {
  final pageName = "imagePicker".obs;
  final ApiRepository apiRepository;
  late ImagePickerConfigs imageConfig;

  RxList<String> imgObjs = <String>[].obs;

  CommodityAddController({required this.apiRepository});

  @override
  void onInit() {
    imageConfig = ImagePickerConfigs();
    imageConfig.appBarTextColor = Colors.white;
    imageConfig.appBarBackgroundColor = Colors.black54;
    imageConfig.stickerFeatureEnabled = false; // ON/OFF features
    imageConfig.translateFunc = (name, value) => name.tr;
    imageConfig.iconCamera = FontAwesomeIcons.camera;
    imageConfig.doneButtonStyle = DoneButtonStyle.outlinedButton;
    imageConfig.adjustFeatureEnabled = false;
    imageConfig.externalImageEditors['external_image_editor_1'] = EditorParams(
      title: 'external_image_editor_1',
      icon: Icons.edit_rounded,
      onEditorEvent: (
              {required BuildContext context,
              required File file,
              required String title,
              int maxWidth = 1080,
              int maxHeight = 1920,
              int compressQuality = 90,
              ImagePickerConfigs? configs}) async =>
          navigator!.push(
        MaterialPageRoute(
          fullscreenDialog: true,
          builder: (context) => ImageEdit(
              file: file,
              title: title,
              maxWidth: maxWidth,
              maxHeight: maxHeight,
              configs: configs),
        ),
      ),
    );
    imageConfig.imagePreProcessingBeforeEditingEnabled = true;
    imageConfig.filterFeatureEnabled = false;
    imageConfig.imagePreProcessingEnabled = true;
    imageConfig.cropFeatureEnabled = false;

    super.onInit();
  }

  void getImages() async {
    List<ImageObject> objects = await navigator!.push(
      MaterialPageRoute(
        builder: (_) {
          return ImagePicker(maxCount: 5);
        },
      ),
    );
    if (objects.length > 0) {
      imgObjs.addAll(objects.map((e) => e.modifiedPath).toList());
    }
  }
}

四、最后注意事项

ImagePickerConfigs 为imagePicker 配置信息。该插件在弹出图片选择界面后，显示语言默认 英文显示。

imageConfig.translateFunc = (name, value) => name.tr; 用于配置 imagePicker语言国际化。

getx 多语言配置：

1. 文件结构：
   
2. 文件内容：

translation_service.dart：

import 'dart:ui';

import 'package:get/get.dart';

import 'en_US.dart';
import 'zh_CN.dart';

class TranslationService extends Translations {
  static Locale? get locale => Get.deviceLocale;
  static final fallbackLocale = Locale('zh', 'CN');
  @override
  Map<String, Map<String, String>> get keys => {
        'zh_CN': zh_CN,
        'en_US': en_US,
      };
}

en_US.dart

const Map<String, String> en_US = {
  'name': 'name',
  'image_picker_camera_title': 'camera',
  'image_picker_album_title': 'album',

  'image_picker_select_button_title': 'select',
  'image_picker_select_images_title': 'selected images count:',
  'image_picker_select_images_guide': 'drag images for sorting list...:',
  'image_picker_exposure_title':'exposure',
  'image_picker_exposure_locked_title':'locked',
  'image_picker_exposure_auto_title':'auto',
};

zh_CN.dart

const Map<String, String> zh_CN = {
  'name': '用户名',
  'image_picker_camera_title': '相机',
  'image_picker_album_title': '相册',
  'image_picker_select_button_title': '确定',
  'image_picker_select_images_title': '已选择:',
  'image_picker_select_images_guide': '拖动图片重新排序:',
  'image_picker_exposure_title': '滤镜',
  'image_picker_exposure_locked_title': '锁定',
  'image_picker_exposure_auto_title': '自动',
  'image_picker_confirm': '确定',
  'image_picker_confirm_delete': '是否要删除这张照片',
  'no': '否',
  'yes': '是',
  'image_picker_exit_without_selecting': '是否要退出而不选择图像？',
  'image_picker_preview_title': '预览',
  'image_picker_image_edit_title': '编辑',
  'image_picker_image_edit_contrast': '对比度',
  'image_picker_image_edit_brightness': '亮度',
  'image_picker_image_edit_saturation': '饱和度',
  'image_picker_image_filter_title': '滤镜',
  'image_picker_confirm_reset_changes': '是否重置更改？',
};

main.dart 中 需要 传递参数给GetMaterialApp来定义语言和翻译。

return GetMaterialApp(
    translations: Messages(), // 你的翻译
    locale: Locale('zh', 'CN'), // 将会按照此处指定的语言翻译
    fallbackLocale: Locale('en', 'US'), // 添加一个回调语言选项，以备上面指定的语言翻译不存在
);

项目中的配置：