No such file or directory in Android 10 (api 29)

问题

I am working on a photo editor app in which after editing my picture I save it into my local storage. It is working fine till android 9 but not on android 10. It shows exception of "No such file or directory found" in Android 10. After some research I found that getExternalFilesDir() is deprecated in android Q+. But I cannot find any proper way to do it in android 10. So please if anyone can provide a tutorial it would be really helpful.

I've added and granted uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> in case of it was the issue, and it didn't solve anything.

This is my try (Used ParcelFileDescriptor):

private void fileAccessForAndroidQ(Uri fileUri){
    try {
        ParcelFileDescriptor parcelFileDescriptor = this.getContentResolver().openFileDescriptor(fileUri, "r", null);
        InputStream inputStream = new FileInputStream(parcelFileDescriptor.getFileDescriptor());
        Cursor returnCursor =
                getContentResolver().query(fileUri, null, null, null, null);
        int nameIndex = returnCursor.getColumnIndex(OpenableColumns.DISPLAY_NAME);
        returnCursor.moveToFirst();
        fileName = returnCursor.getString(nameIndex);

        file = new File(this.getFilesDir(), fileName);

        OutputStream outputStream = new FileOutputStream(file);
        IOUtils.copyStream(inputStream, outputStream);

    }catch (Exception e){
        Toast.makeText(this, ""+e.getMessage(), Toast.LENGTH_SHORT).show();
    }
}

Any kind of help would be appreciated.

回答1:

If you target Android 10 (API level 29) or higher, set the value of requestLegacyExternalStorage to true in your app's manifest file:

Documentation

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.appname"
    android:installLocation="auto">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:requestLegacyExternalStorage="true"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme.NoActionBar">

        <activity android:name=".activities.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>


    </application>

</manifest>

回答2:

Here is the best I could find: https://developer.android.com/training/data-storage/app-specific#external

Basically, you now use app-specific directories for your files. For example:

@Nullable
File getAppSpecificAlbumStorageDir(Context context, String albumName) {
    // Get the pictures directory that's inside the app-specific directory on
    // external storage.
    File file = new File(context.getExternalFilesDir(
            Environment.DIRECTORY_PICTURES), albumName);
    if (file == null || !file.mkdirs()) {
        Log.e(LOG_TAG, "Directory not created");
    }
    return file;
}

回答3:

I found this working for me. i am trying to list all file on ListView

if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, 0);

    } else {


        File s = Environment.getExternalStorageDirectory();
        Log.d("Path ",Arrays.toString(s.listFiles()));
        File[] s1 = new File[s.listFiles().length];

        for(int i=0;i<s.listFiles().length;i++){
            s1[i]= new File(s.listFiles()[i].toString().replace("/storage/emulated/0/", ""));
        }



        ArrayAdapter<File> adapter = new ArrayAdapter<File>(this,R.layout.support_simple_spinner_dropdown_item,s1);
        l1.setAdapter(adapter);

     }

来源：https://stackoverflow.com/questions/61629593/no-such-file-or-directory-in-android-10-api-29