android - 写入外部存储权限始终被拒绝

Question

我正在使用下载管理器在我的 android 应用程序中下载图像。
为了获得“WRITE_EXTERNAL_STORAGE”许可，我要起诉 Dexter图书馆。

        Dexter.withContext(getApplicationContext())
            .withPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE)
            .withListener(new PermissionListener() {
                @Override
                public void onPermissionGranted(PermissionGrantedResponse permissionGrantedResponse) {
                    Toast.makeText(LiveTaskActivity.this, "Granted", Toast.LENGTH_SHORT).show();
                }

                @Override
                public void onPermissionDenied(PermissionDeniedResponse permissionDeniedResponse) {
                    Toast.makeText(LiveTaskActivity.this, "Denied", Toast.LENGTH_SHORT).show();
                }

                @Override
                public void onPermissionRationaleShouldBeShown(PermissionRequest permissionRequest, PermissionToken permissionToken) {

                }
            }).check();

但即使我手动接受从应用程序授予权限的权限，我也总是获得“拒绝”权限。我还尝试手动实现权限请求代码。

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED
            || ActivityCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {

        ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);
    } else {
        download();
    }

尽管如此，我还是无法获得许可。这是 list 代码:

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

    <application
      android:requestLegacyExternalStorage="true"

这是我的 buil.gradle(app) 代码:

android {
compileSdkVersion 30
buildToolsVersion "30.0.3"

defaultConfig {
    applicationId "app.gigg.me.app"
    minSdkVersion 22
    targetSdkVersion 30
    versionCode 2
    versionName '1.0.1'

请帮我解决这个问题。
**更新这是我的下载代码

    private void startDownload() {
    Toast.makeText(this, "Downloading File...", Toast.LENGTH_SHORT).show();
    fileName = link.substring(link.lastIndexOf("/") + 1) + ".png";
    File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).getPath(), fileName);
    DownloadManager.Request request = new DownloadManager.Request(Uri.parse(link))
            .setTitle(fileName)
            .setDescription("Downloading")
            .setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED)
            .setDestinationUri(Uri.fromFile(file))
            .setMimeType("image/*")
            .setAllowedOverMetered(true)
            .setAllowedOverRoaming(true);
    download_id = downloadManager.enqueue(request);
}

Answer 1

WRITE_EXTERNAL_STORAGE面向 Android 11 ( targetSdkVersion 30 ) 时不可用。
你可以在这里阅读更多:https://developer.android.com/about/versions/11/privacy/storage