java.io.FileNotFoundException 打開失敗：EPERM（不允許操作）

Question

修改 build.gradle 后： compileSdkVersion 28 to 32 targetSdkVersion 28 to 32 我無法從改造響應中寫入本地文件。 我得到錯誤：

java.io.FileNotFoundException: /storage/emulated/0/DontEat/rangt_00001.jpg: open failed: EPERM (Operation not permitted)

AndroidManifest.xml 包含：

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

我的代碼是：

public static void downloadFile(SyncCalls.CallbacksDownload callbacks, final String type, final File file, final Boolean last) {
    final WeakReference<SyncCalls.CallbacksDownload> callbacksWeakReference = new WeakReference<>(callbacks);
    SyncService service = SyncService.retrofit.create(SyncService.class);
    String filename = file.toString().split("/")[5];
    Call<ResponseBody> call = service.downloadFile(filename);
    call.enqueue(new Callback<ResponseBody>() {
        @Override
        public void onResponse(@NonNull Call<ResponseBody> call, @NonNull Response<ResponseBody> response) {
            try {
                OutputStream out = null;
                InputStream in = null;
                ResponseBody body = response.body();
                try {
                    if (body != null) {
                        in = body.byteStream();
                        out = new FileOutputStream(file);
                        byte[] fileReader = new byte[4096];
                        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
                        StrictMode.setThreadPolicy(policy);
                        while (true) {
                            int read = in.read(fileReader);
                            if (read == -1) {
                                break;
                            }
                            out.write(fileReader, 0, read);
                        }
                        out.flush();
                    }
                } catch (IOException e) {
                    if (BuildConfig.DEBUG) Log.v(Consts.TAG, e.toString());
                } finally {
                    if (in != null) {
                        in.close();
                    }
                    if (out != null) {
                        out.close();
                    }
                }

            } catch (IOException e) {
                if (BuildConfig.DEBUG) Log.v(Consts.TAG, e.toString());
            }
            if (BuildConfig.DEBUG) Log.v(Consts.TAG, "download " + file.toString());
            if (callbacksWeakReference.get() != null)
                callbacksWeakReference.get().onResponseSync(type, "down", last);

        }

權限通過以下方式驗證：

// Storage Permissions variables
private static final int REQUEST_EXTERNAL_STORAGE = 1;
private static final String[] PERMISSIONS_STORAGE = {
        Manifest.permission.READ_EXTERNAL_STORAGE,
        Manifest.permission.WRITE_EXTERNAL_STORAGE
};
//permission method.
public static void verifyStoragePermissions(Activity activity) {
    // Check if we have read or write permission
    int writePermission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);
    int readPermission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.READ_EXTERNAL_STORAGE);

    if (writePermission != PackageManager.PERMISSION_GRANTED || readPermission != PackageManager.PERMISSION_GRANTED) {
        // We don't have permission so prompt the user
        ActivityCompat.requestPermissions(
                activity,
                PERMISSIONS_STORAGE,
                REQUEST_EXTERNAL_STORAGE
        );
    }
}

請問是我的代碼錯誤還是權限錯誤？

由於我的英語非常有限，我沒有發展更多。 （這是我多年前制作的一個應用程序，僅供個人使用，家庭，但我無法擴展它，因為這個錯誤出現在新的 android 版本中，而到目前為止它運行良好）

編輯：實際上，我認為我將問題顛倒過來，我最好將應用程序的內部數據目錄與 getFilesDir() 一起使用，如果我理解正確，我將不再有權限問題。

Answer 1

在AndroidManifest.xml中添加該行，在應用程序標簽內。希望它會幫助你。

android:requestLegacyExternalStorage=”true”