我只是试着把原生的react应用和django后端连接起来。
所以在Django中我安装了django.cors.headers，并在设置中进行了配置。
我使用的是android studio。我使用的是模拟器。效果很好。
我在django中设置了cors：

MIDDLEWARE = [
    "django.middleware.security.SecurityMiddleware",
    "django.contrib.sessions.middleware.SessionMiddleware",
    "corsheaders.middleware.CorsMiddleware",
    "django.middleware.common.CommonMiddleware",
    "django.middleware.csrf.CsrfViewMiddleware",
    "django.contrib.auth.middleware.AuthenticationMiddleware",
    "django.contrib.messages.middleware.MessageMiddleware",
    "django.middleware.clickjacking.XFrameOptionsMiddleware",
]

CORS_ORIGIN_ALLOW_ALL = False
CORS_ORIGIN_WHITELIST = [
    "http://localhost:8081",
    "http://localhost:19006",
    "http://localhost:19002",
    "http://192.168.1.69:19000",
]

并自然React

useEffect(() => {
        fetch("http://127.0.0.1:8000/animalGroups/group/", {
            method: "GET",
            headers: {
                Accept: "application/json",
                "Content-Type": "application/json",
            },
        })
            .then((res) => res.json())
            .then((jsonres) => setAnimalGroup(jsonres))
            .catch((error) => console.error(error));
    }, []);

所以在 Postman 这行很顺利：
我得到了正确的回答：

[
    {
        "group_name": "zoogdieren",
        "description": "Dit zijn zoogdieren"
    },
    {
        "group_name": "vissen",
        "description": "Dit is de hoofgroep vissen"
    }
]

这是react native中的消息：

Opening on Android...
› Opening exp://192.168.1.69:19000 on MY_ANDROID
› Press ? │ show all commands
› Reloading apps
Android Bundling complete

但我仍然得到这个错误：

Network request failed
at node_modules\whatwg-fetch\dist\fetch.umd.js:null in setTimeout$argument_0
at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:null in _allocateCallback$argument_0
at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:null in _callTimer
at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:null in callTimers
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in __callFunction
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in __guard$argument_0
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in __guard
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:null in callFunctionReturnFlushedQueue

那我要改变什么呢？
谢谢