Question

我最近退出了我的本地反应项目，并且相机功能不起作用。该代码允许用户上传图像。它可以与expo一起使用，但是在弹出并在Android上运行后，它停止了工作。这是摄像机上传的代码：

import * as Permissions from 'expo-permissions';
import * as ImagePicker from 'expo-image-picker';

    _checkPermissions = async () => {
        const { status } = await Permissions.askAsync(Permissions.CAMERA);
        this.setState({
            camera: status
        });

        // take permission for Gallery, aka CameraRoll
        const { statusRoll } = await Permissions.askAsync(Permissions.CAMERA_ROLL);
        this.setState({
            cameraRoll: statusRoll
        });
    };


    findNewImage = async () => {
        this._checkPermissions();

        let result = await ImagePicker.launchCameraAsync({
            mediaTypes: "Images",
            allowsEditing: true,
            quality: 1
        });

        console.log("image picked is = result = ", result);

        if (!result.cancelled) {

            console.log("upload image");
            this.setState({
                imageSelected: true,
                imageId: this.uniqueId(),
                uri: result.uri
            });

        } else {

            console.log("cancel");
            this.setState({
                imageSelected: false
            });

        }
    };

但是，出现此错误：

W/ReactNativeJS: Possible Unhandled Promise Rejection (id: 3):
    TypeError: undefined is not an object (evaluating '_ExpoPermissions.default.askAsync')
    askAsync$@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:172905:109
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23241:32
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23142:30
    http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23172:19
    tryCallTwo@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24367:9
    doResolve@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24531:25
    Promise@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24390:14
    callInvokeWithMethodAndArg@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23171:29
    enqueue@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23176:157
    async@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23192:69
    askAsync@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:172896:38
    _callee$@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141098:71
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23241:32
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23142:30
    http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23172:19
    tryCallTwo@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24367:9
    doResolve@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24531:25
    Promise@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24390:14
    callInvokeWithMethodAndArg@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23171:29
    enqueue@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23176:157
    async@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23192:69
    _callee@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141093:42
    _callee2$@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141141:40
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23241:32
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23142:30
    http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23172:19
    tryCallTwo@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24367:9
    doResolve@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24531:25
    Promise@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24390:14
    callInvokeWithMethodAndArg@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23171:29
    enqueue@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23176:157
    async@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23192:69
    _callee2@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141137:42
    onPress@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141457:39
    touchableHandlePress@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:51687:47
    touchableHandlePress@[native code]
    _performSideEffectsForTransition@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:50367:36
    _performSideEffectsForTransition@[native code]
    _rec
W/ReactNativeJS: Possible Unhandled Promise Rejection (id: 4):
    TypeError: undefined is not an object (evaluating '_ExponentImagePicker.default.launchCameraAsync')
    launchCameraAsync$@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:173085:45
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23241:32
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23142:30
    http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23172:19
    tryCallTwo@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24367:9
    doResolve@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24531:25
    Promise@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24390:14
    callInvokeWithMethodAndArg@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23171:29
    enqueue@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23176:157
    async@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23192:69
    launchCameraAsync@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:173079:38
    _callee2$@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141144:80
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23241:32
    tryCatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23066:23
    invoke@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23142:30
    http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23172:19
    tryCallTwo@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24367:9
    doResolve@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24531:25
    Promise@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:24390:14
    callInvokeWithMethodAndArg@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23171:29
    enqueue@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23176:157
    async@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:23192:69
    _callee2@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141137:42
    onPress@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:141457:39
    touchableHandlePress@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:51687:47
    touchableHandlePress@[native code]
    _performSideEffectsForTransition@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:50367:36
    _performSideEffectsForTransition@[native code]
    _receiveSignal@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:50293:46
    _receiveSignal@[native code]
    touchableHandleResponderRelease@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:50172:26
    touchableHandleResponderRelease@[native code]
    invokeGuardedCallbackImpl@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:8533:21
    invokeGuardedCallback@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:8624:42
    invokeGuardedCallbackAndCatchFirstError@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:8628:36
    executeDispatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:8822:48
    executeDispatchesInOrder@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:8842:26
    executeDispatchesAndRelease@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:8937:35
    forEach@[native code]
    forEachAccumulated@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:8927:22
    runEventsInBatch@http://10.0.2.2:8081/index.delta?platform=android&dev=true&minify=false:9031:27
    runExtrac

我的应用程序中有一个上传按钮，当我单击它时，此错误消息出现在Android Studio控制台中。与Expo的配合正常。

这是我的package.json：

{
  "scripts": {
    "start": "react-native start",
    "android": "react-native run-android",
    "ios": "react-native run-ios",
    "web": "expo start --web"
  },
  "dependencies": {
    "@expo/samples": "~3.0.0",
    "@expo/vector-icons": "^10.0.2",
    "@unimodules/core": "^2.0.1",
    "@unimodules/react-native-adapter": "^2.0.1",
    "expo-asset": "^5.0.0",
    "expo-constants": "^5.0.0",
    "expo-file-system": "^5.0.1",
    "expo-font": "^5.0.0",
    "expo-image-picker": "^5.0.2",
    "expo-permissions": "^5.0.1",
    "expo-web-browser": "^5.0.0",
    "firebase": "^6.1.1",
    "react": "16.8.3",
    "react-dom": "^16.8.6",
    "react-native": "0.59.8",
    "react-native-elements": "^1.1.0",
    "react-native-gesture-handler": "^1.3.0",
    "react-native-paper": "^2.16.0",
    "react-native-permissions": "^1.1.1",
    "react-native-vector-icons": "^6.5.0",
    "react-native-web": "^0.11.4",
    "react-navigation": "^3.11.0",
    "react-navigation-material-bottom-tabs": "^1.0.0",
    "remove-node-modules": "^1.7.4"
  },
  "devDependencies": {
    "babel-preset-expo": "^5.1.0"
  },
  "private": true
}

Answer 1

如果要带出 React-native project ，而不是 Expo ，

您应该使用React-native-unimodules而不是自己安装模块。

npm install react-native-unimodules

该库包含核心Unimodule基础结构以及其他Unimodule通常依赖的Unimodule和接口的集合。您需要先安装此软件，然后才能使用Foundation中的库，例如expo-camera，expo-media-library等。

配置Android

在android / settings.gradle的顶部，从以下位置添加Apply： '../node_modules/react-native-unimodules/gradle.groovy'，然后打开下一行添加includeUnimodulesProjects（）。
添加适用于： '../../node_modules/react-native-unimodules/gradle.groovy'在任何地方在android / app / build.gradle中，然后addUnimodulesDependencies（）内部依赖项{}块。
例如，如果您需要自定义node_modules的路径因为您正在使用纱线工作区，所以可以传入参数这两个功能的路径： includeUnimodulesProjects（[[modulesPaths： ['./path/to/node_modules']]）， addUnimodulesDependencies（[modulesPaths：['./path/to/node_modules']]）
如果您需要排除一些未使用的unimodule，但是它们是由您的其他依赖项（例如expo）安装的，然后您可以为此传递排除参数。例如，如果您想排除expo-face-detector，您可能要使用此功能： addUnimodulesDependencies（[排除：['expo-face-detector']]）
您还可以自定义unimodule的配置依赖（默认是实现，如果您使用的是Gradle 低于3.0，则需要设置配置： addUnimodulesDependencies，例如： addUnimodulesDependencies（[configuration：“ compile”]））
我们建议使用Java 1.8，您可以在 android / app / build.gradle like this.
将android / build.gradle中的minSdkVersion更新为21。
根据this diff.更新您的MainApplication.java

向AndroidManifest.xml添加权限

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<uses-permission android:name="android.permission.READ_CALENDAR" />
<uses-permission android:name="android.permission.WRITE_CALENDAR" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_SETTINGS" />

您可能不必直接使用此软件包提供的任何代码，只能由您安装的其他Unimodules使用。

但是您很可能希望使用诸如FileSystem或Permissions之类的方法，并且可以这样导入以下模块：

import {
  Asset,
  Constants,
  FileSystem,
  Permissions,
} from 'react-native-unimodules';

如果您想了解更多about this,

Answer 2

我在使用react-native-contacts时也遇到了相同的错误。尝试在.then（）之后添加.catch（）块，它解决了我的问题。

PermissionsAndroid.request(
            PermissionsAndroid.PERMISSIONS.READ_CONTACTS,
            {
              'title': 'Contacts',
              'message': 'This app would like to view your contacts.'
            }
          ).then(() => {
            con.getAll((err, contacts) => {
              if (err === 'denied'){
                // error
              } else {
                // contacts returned in Array
                console.log(contacts);
              }
            })
          })
          .catch((err)=> {
              console.log(err);
          })

Answer 3

总是尝试为所有等待的事件添加一个捕获块。

例如

await Permissions.askAsync(Permissions.CAMERA).catch(err=>{});

也适用于其他地方。

W / ReactNativeJS：可能的未处理承诺拒绝（ID：3和4）

3 个答案: