Develop Reference

Is it possible to get Android SD card location on SAMSUNG Tablet / Android 11

I have looked over many posts on getting SD card locations, and most that mention using Environment.getExternalStorageState(), Environment.getExternalStorageDirectory() always returns internal storage for my on a Samsung Galaxy Tab A / Android 11 (/storage/emulated/0)
I did see a comment that said to use System.getenv("SECONDARY_STORAGE"), which returns /storage/sdcard:/storage/usb1:/storage/usb2, but trying to open a file (I have put there) just returns a not found error (ie java.io.FileNotFoundException: /sdcard/external_sd/Music/test/testfile.mp3: open failed: ENOENT (No such file or directory).
Also tried Environment.getExternalStoragePublicDirectory(Environment.MEDIA_MOUNTED).getPath() and this returns /storage/emulated/0/mounted and this does not work either
I have the following permissions..
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.PERMISSIONS_STORAGE" />
<uses-permission android:name="android.permission.REQUEST_EXTERNAL_STORAGE" />
and at startup I call
private fun verifyStoragePermissions(activity: Activity) {
// Check if we have write permission
val permission =
ActivityCompat.checkSelfPermission(activity, READ_EXTERNAL_STORAGE)
if (permission != PackageManager.PERMISSION_GRANTED) {
// We don't have permission so prompt the user
ActivityCompat.requestPermissions(
activity,
arrayOf(READ_EXTERNAL_STORAGE, WRITE_EXTERNAL_STORAGE),
)
}
}
Finally, as stated here, I hardwired /sdcard/external_sd and this did not work either (ie I try to open a file I know is there, and also using the following to list contents..
File(testFolder).walk().forEach {
println(it)
}
I have other application that writes to it, so there must be some way to do it (I only want to read existing files).
What might I be doing wrong?

You can try this:
File[] dirs = getExternalFilesDirs("");
for (File currD :
dirs) {
if (currD.getAbsolutePath().equals(getExternalFilesDir("").getAbsolutePath())) {
// Here is internal storage path
} else {
// Here is SD path
}
}

Android 11 - Install an apk using a system app [duplicate]

I am getting
open failed: EACCES (Permission denied)
on the line OutputStream myOutput = new FileOutputStream(outFileName);
I checked the root, and I tried android.permission.WRITE_EXTERNAL_STORAGE.
How can I fix this problem?
try {
InputStream myInput;
myInput = getAssets().open("XXX.db");
// Path to the just created empty db
String outFileName = "/data/data/XX/databases/"
+ "XXX.db";
// Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
// Transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0) {
myOutput.write(buffer, 0, length);
}
// Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
buffer = null;
outFileName = null;
}
catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}

Google has a new feature on Android Q: filtered view for external storage. A quick fix for that is to add this code in the AndroidManifest.xml file:
<manifest ... >
<!-- This attribute is "false" by default on apps targeting Android Q. -->
<application android:requestLegacyExternalStorage="true" ... >
...
</application>
</manifest>
You can read more about it here: https://developer.android.com/training/data-storage/use-cases
Edit: I am starting to get downvotes because this answer is out of date for Android 11. So whoever sees this answer please go to the link above and read the instructions.

For API 23+ you need to request the read/write permissions even if they are already in your manifest.
// Storage Permissions
private static final int REQUEST_EXTERNAL_STORAGE = 1;
private static String[] PERMISSIONS_STORAGE = {
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE
};
/**
* Checks if the app has permission to write to device storage
*
* If the app does not has permission then the user will be prompted to grant permissions
*
* #param activity
*/
public static void verifyStoragePermissions(Activity activity) {
// Check if we have write permission
int permission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);
if (permission != PackageManager.PERMISSION_GRANTED) {
// We don't have permission so prompt the user
ActivityCompat.requestPermissions(
activity,
PERMISSIONS_STORAGE,
REQUEST_EXTERNAL_STORAGE
);
}
}
AndroidManifest.xml
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
For official documentation about requesting permissions for API 23+, check https://developer.android.com/training/permissions/requesting.html

I had the same problem... The <uses-permission was in the wrong place. This is right:
<manifest>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
...
<application>
...
<activity>
...
</activity>
</application>
</manifest>
The uses-permission tag needs to be outside the application tag.

Add android:requestLegacyExternalStorage="true" to the Android Manifest
It's worked with Android 10 (Q) at SDK 29+
or After migrating Android X.
<application
android:name=".MyApplication"
android:allowBackup="true"
android:hardwareAccelerated="true"
android:icon=""
android:label=""
android:largeHeap="true"
android:supportsRtl=""
android:theme=""
android:requestLegacyExternalStorage="true">

I have observed this once when running the application inside the emulator. In the emulator settings, you need to specify the size of external storage ("SD Card") properly. By default, the "external storage" field is empty, and that probably means there is no such device and EACCES is thrown even if permissions are granted in the manifest.

In addition to all the answers, make sure you're not using your phone as a USB storage.
I was having the same problem on HTC Sensation on USB storage mode enabled. I can still debug/run the app, but I can't save to external storage.

My issue was with "TargetApi(23)" which is needed if your minSdkVersion is bellow 23.
So, I have request permission with the following snippet
protected boolean shouldAskPermissions() {
return (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1);
}
#TargetApi(23)
protected void askPermissions() {
String[] permissions = {
"android.permission.READ_EXTERNAL_STORAGE",
"android.permission.WRITE_EXTERNAL_STORAGE"
};
int requestCode = 200;
requestPermissions(permissions, requestCode);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// ...
if (shouldAskPermissions()) {
askPermissions();
}
}

Be aware that the solution:
<application ...
android:requestLegacyExternalStorage="true" ... >
Is temporary, sooner or later your app should be migrated to use Scoped Storage.
In Android 10, you can use the suggested solution to bypass the system restrictions, but in Android 11 (R) it is mandatory to use scoped storage, and your app might break if you kept using the old logic!
This video might be a good help.

Android 10 (API 29) introduces Scoped Storage. Changing your manifest to request legacy storage is not a long-term solution.
I fixed the issue when I replaced my previous instances of Environment.getExternalStorageDirectory() (which is deprecated with API 29) with context.getExternalFilesDir(null).
Note that context.getExternalFilesDir(type) can return null if the storage location isn't available, so be sure to check that whenever you're checking if you have external permissions.
Read more here.

I'm experiencing the same. What I found is that if you go to Settings -> Application Manager -> Your App -> Permissions -> Enable Storage, it solves the issue.

It turned out, it was a stupid mistake since I had my phone still connected to the desktop PC and didn't realize this.
So I had to turn off the USB connection and everything worked fine.

I had the same problem on Samsung Galaxy Note 3, running CM 12.1. The issue for me was that i had
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="18"/>
and had to use it to take and store user photos. When I tried to load those same photos in ImageLoader i got the (Permission denied) error. The solution was to explicitly add
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
since the above permission only limits the write permission up to API version 18, and with it the read permission.

In addition to all answers, if the clients are using Android 6.0, Android added new permission model for (Marshmallow).
Trick: If you are targeting version 22 or below, your application will request all permissions at install time just as it would on any device running an OS below Marshmallow. If you are trying on the emulator then from android 6.0 onwards you need to explicitly go the settings->apps-> YOURAPP -> permissions and change the permission if you have given any.

Strangely after putting a slash "/" before my newFile my problem was solved. I changed this:
File myFile= new File(Environment.getExternalStorageDirectory() + "newFile");
to this:
File myFile= new File(Environment.getExternalStorageDirectory() + "/newFile");
UPDATE:
as mentioned in the comments, the right way to do this is:
File myFile= new File(Environment.getExternalStorageDirectory(), "newFile");

I had the same problem and none of suggestions helped. But I found an interesting reason for that, on a physical device, Galaxy Tab.
When USB storage is on, external storage read and write permissions don't have any effect.
Just turn off USB storage, and with the correct permissions, you'll have the problem solved.

I would expect everything below /data to belong to "internal storage". You should, however, be able to write to /sdcard.

Change a permission property in your /system/etc/permission/platform.xml
and group need to mentioned as like below.
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE">
<group android:gid="sdcard_rw" />
<group android:gid="media_rw" />
</uses-permission>

I had the same error when was trying to write an image in DCIM/camera folder on Galaxy S5 (android 6.0.1) and I figured out that only this folder is restricted. I simply could write into DCIM/any folder but not in camera.
This should be brand based restriction/customization.

Maybe the answer is this:
on the API >= 23 devices, if you install app (the app is not system app), you should check the storage permission in "Setting - applications", there is permission list for every app, you should check it on! try

To store a file in a directory which is foreign to the app's directory is restricted above API 29+. So to generate a new file or to create a new file use your application directory like this :-
So the correct approach is :-
val file = File(appContext.applicationInfo.dataDir + File.separator + "anyRandomFileName/")
You can write any data into this generated file !
The above file is accessible and would not throw any exception because it resides in your own developed app's directory.
The other option is android:requestLegacyExternalStorage="true" in manifest application tag as suggested by Uriel but its not a permanent solution !

When your application belongs to the system application, it can't access the SD card.

keep in mind that even if you set all the correct permissions in the manifest:
The only place 3rd party apps are allowed to write on your external card are "their own directories"
(i.e. /sdcard/Android/data/)
trying to write to anywhere else: you will get exception:
EACCES (Permission denied)

Environment.getExternalStoragePublicDirectory();
When using this deprecated method from Android 29 onwards you will receive the same error:
java.io.FileNotFoundException: open failed: EACCES (Permission denied)
Resolution here:
getExternalStoragePublicDirectory deprecated in Android Q

In my case I was using a file picker library which returned the path to external storage but it started from /root/. And even with the WRITE_EXTERNAL_STORAGE permission granted at runtime I still got error EACCES (Permission denied).
So use Environment.getExternalStorageDirectory() to get the correct path to external storage.
Example:
Cannot write: /root/storage/emulated/0/newfile.txt
Can write: /storage/emulated/0/newfile.txt
boolean externalStorageWritable = isExternalStorageWritable();
File file = new File(filePath);
boolean canWrite = file.canWrite();
boolean isFile = file.isFile();
long usableSpace = file.getUsableSpace();
Log.d(TAG, "externalStorageWritable: " + externalStorageWritable);
Log.d(TAG, "filePath: " + filePath);
Log.d(TAG, "canWrite: " + canWrite);
Log.d(TAG, "isFile: " + isFile);
Log.d(TAG, "usableSpace: " + usableSpace);
/* Checks if external storage is available for read and write */
public boolean isExternalStorageWritable() {
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
return true;
}
return false;
}
Output 1:
externalStorageWritable: true
filePath: /root/storage/emulated/0/newfile.txt
isFile: false
usableSpace: 0
Output 2:
externalStorageWritable: true
filePath: /storage/emulated/0/newfile.txt
isFile: true
usableSpace: 1331007488

I am creating a folder under /data/ in my init.rc (mucking around with the aosp on Nexus 7) and had exactly this problem.
It turned out that giving the folder rw (666) permission was not sufficient and it had to be rwx (777) then it all worked!

The post 6.0 enforcement of storage permissions can be bypassed if you have a rooted device via these adb commands:
root#msm8996:/ # getenforce
getenforce
Enforcing
root#msm8996:/ # setenforce 0
setenforce 0
root#msm8996:/ # getenforce
getenforce
Permissive

i faced the same error on xiaomi devices (android 10 ). The following code fixed my problem.
Libraries: Dexter(https://github.com/Karumi/Dexter) and Image picker(https://github.com/Dhaval2404/ImagePicker)
Add manifest ( android:requestLegacyExternalStorage="true")
public void showPickImageSheet(AddImageModel model) {
BottomSheetHelper.showPickImageSheet(this, new BottomSheetHelper.PickImageDialogListener() {
#Override
public void onChooseFromGalleryClicked(Dialog dialog) {
selectedImagePickerPosition = model.getPosition();
Dexter.withContext(OrderReviewActivity.this) .withPermissions(Manifest.permission.READ_EXTERNAL_STORAGE)
.withListener(new MultiplePermissionsListener() {
#Override
public void onPermissionsChecked(MultiplePermissionsReport report) {
if (report.areAllPermissionsGranted()) {
ImagePicker.with(OrderReviewActivity.this)
.galleryOnly()
.compress(512)
.maxResultSize(852,480)
.start();
}
}
#Override
public void onPermissionRationaleShouldBeShown(List<PermissionRequest> list, PermissionToken permissionToken) {
permissionToken.continuePermissionRequest();
}
}).check();
dialog.dismiss();
}
#Override
public void onTakePhotoClicked(Dialog dialog) {
selectedImagePickerPosition = model.getPosition();
ImagePicker.with(OrderReviewActivity.this)
.cameraOnly()
.compress(512)
.maxResultSize(852,480)
.start();
dialog.dismiss();
}
#Override
public void onCancelButtonClicked(Dialog dialog) {
dialog.dismiss();
}
});
}

In my case the error was appearing on the line
target.createNewFile();
since I could not create a new file on the sd card,so I had to use the DocumentFile approach.
documentFile.createFile(mime, target.getName());
For the above question the problem may be solved with this approach,
fos=context.getContentResolver().openOutputStream(documentFile.getUri());
See this thread too,
How to use the new SD card access API presented for Android 5.0 (Lollipop)?

I Use the below process to handle the case with android 11 and targetapi30
As pre-created file dir as per scoped storage in my case in root dir files//<Image/Video... as per requirement>
Copy picked file and copy the file in cache directory at the time of picking from my external storage
Then at a time to upload ( on my send/upload button click) copy the file from cache dir to my scoped storage dir and then do my upload process
use this solution due to at time upload app in play store it generates warning for MANAGE_EXTERNAL_STORAGE permission and sometimes rejected from play store in my case.
Also as we used target API 30 so we can't share or forward file from our internal storage to app

2022 Kotlin way to ask permission:
private val writeStoragePermissionResult =
registerForActivityResult(ActivityResultContracts.RequestMultiplePermissions()) { permissions ->}
private fun askForStoragePermission(): Boolean =
if (hasPermissions(
requireContext(),
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE
)
) {
true
} else {
writeStoragePermissionResult.launch(
arrayOf(
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE,
)
)
false
}
fun hasPermissions(context: Context, vararg permissions: String): Boolean = permissions.all {
ActivityCompat.checkSelfPermission(context, it) == PackageManager.PERMISSION_GRANTED
}

How to read a file directly from external download directory on Android 10 (Q)

I am trying to read a file from the download folder on Android Q by doing this:
File downloadDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
File f = new File(downloadDir, "some-existing-file");
if(!f.exists()) {
throw new IllegalStateException();
}
Uri furi = Uri.fromFile(f);
try {
ParcelFileDescriptor des = getContentResolver().openFileDescriptor(
furi, "r", null);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
I also set android:requestLegacyExternalStorage="true" in the manifest, and requested WRITE_EXTERNAL_STORAGE and READ_EXTERNAL_STORAGE runtime permissions.
The file exists but when trying to open the file descriptor, an exception arises:
java.io.FileNotFoundException: open failed: EACCES (Permission denied).
I read the changes made in Android Q storage, but could not figure out how can I just read the file without having user interaction.
Thanks!

From Android 6 (Marshmallow) some of critical permissions should be granted at runtime by the user so he/she will know what things can your app access.
this link is all what you need
EDIT
add these to manifest
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
then add this code to your oncreate method
if (android.os.Build.VERSION.SDK_INT >= 23 && (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) !=
PackageManager.PERMISSION_GRANTED)) {
ActivityCompat.requestPermissions(
this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
2000);
}
this will popup the user a dialog to agree permissions. if the user agrees onRequestPermissionsResult method will be called, so override onRequestPermissionsResult like this
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults) {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED && requestCode == 2000) {
//do what you want with files
}
}
just pay attention that I set request code to 2000. it's optional.

This method was deprecated in API level 29. To improve user privacy, direct access to shared/external storage devices is deprecated. When an app targets Build.VERSION_CODES.Q, the path returned from this method is no longer directly accessible to apps. Apps can continue to access content stored on shared/external storage by migrating to alternatives such as Context#getExternalFilesDir(String), MediaStore, or Intent#ACTION_OPEN_DOCUMENT.
Copied from Android documents.docs

After too many hours of trying to figure out what the hell is going on, I managed to find a solution.
I addded to the manifest:
android:requestLegacyExternalStorage="true"
When rebuilding and reinstalling directly from Android Studio, the build system or android runtime does not register a change in the manifest, and the request for requestLegacyExternalStorage does not register.
I fixed it by completely uninstalling the app: adb uninstall com.example.app and installing it again from android studio.

TextToSpeech addSpeech(String key_string , String path) is not working [duplicate]

I am getting
open failed: EACCES (Permission denied)
on the line OutputStream myOutput = new FileOutputStream(outFileName);
I checked the root, and I tried android.permission.WRITE_EXTERNAL_STORAGE.
How can I fix this problem?
try {
InputStream myInput;
myInput = getAssets().open("XXX.db");
// Path to the just created empty db
String outFileName = "/data/data/XX/databases/"
+ "XXX.db";
// Open the empty db as the output stream
OutputStream myOutput = new FileOutputStream(outFileName);
// Transfer bytes from the inputfile to the outputfile
byte[] buffer = new byte[1024];
int length;
while ((length = myInput.read(buffer)) > 0) {
myOutput.write(buffer, 0, length);
}
// Close the streams
myOutput.flush();
myOutput.close();
myInput.close();
buffer = null;
outFileName = null;
}
catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}

Google has a new feature on Android Q: filtered view for external storage. A quick fix for that is to add this code in the AndroidManifest.xml file:
<manifest ... >
<!-- This attribute is "false" by default on apps targeting Android Q. -->
<application android:requestLegacyExternalStorage="true" ... >
...
</application>
</manifest>
You can read more about it here: https://developer.android.com/training/data-storage/use-cases
Edit: I am starting to get downvotes because this answer is out of date for Android 11. So whoever sees this answer please go to the link above and read the instructions.

For API 23+ you need to request the read/write permissions even if they are already in your manifest.
// Storage Permissions
private static final int REQUEST_EXTERNAL_STORAGE = 1;
private static String[] PERMISSIONS_STORAGE = {
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE
};
/**
* Checks if the app has permission to write to device storage
*
* If the app does not has permission then the user will be prompted to grant permissions
*
* #param activity
*/
public static void verifyStoragePermissions(Activity activity) {
// Check if we have write permission
int permission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);
if (permission != PackageManager.PERMISSION_GRANTED) {
// We don't have permission so prompt the user
ActivityCompat.requestPermissions(
activity,
PERMISSIONS_STORAGE,
REQUEST_EXTERNAL_STORAGE
);
}
}
AndroidManifest.xml
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
For official documentation about requesting permissions for API 23+, check https://developer.android.com/training/permissions/requesting.html

I had the same problem... The <uses-permission was in the wrong place. This is right:
<manifest>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
...
<application>
...
<activity>
...
</activity>
</application>
</manifest>
The uses-permission tag needs to be outside the application tag.

Add android:requestLegacyExternalStorage="true" to the Android Manifest
It's worked with Android 10 (Q) at SDK 29+
or After migrating Android X.
<application
android:name=".MyApplication"
android:allowBackup="true"
android:hardwareAccelerated="true"
android:icon=""
android:label=""
android:largeHeap="true"
android:supportsRtl=""
android:theme=""
android:requestLegacyExternalStorage="true">

I have observed this once when running the application inside the emulator. In the emulator settings, you need to specify the size of external storage ("SD Card") properly. By default, the "external storage" field is empty, and that probably means there is no such device and EACCES is thrown even if permissions are granted in the manifest.

In addition to all the answers, make sure you're not using your phone as a USB storage.
I was having the same problem on HTC Sensation on USB storage mode enabled. I can still debug/run the app, but I can't save to external storage.

My issue was with "TargetApi(23)" which is needed if your minSdkVersion is bellow 23.
So, I have request permission with the following snippet
protected boolean shouldAskPermissions() {
return (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1);
}
#TargetApi(23)
protected void askPermissions() {
String[] permissions = {
"android.permission.READ_EXTERNAL_STORAGE",
"android.permission.WRITE_EXTERNAL_STORAGE"
};
int requestCode = 200;
requestPermissions(permissions, requestCode);
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// ...
if (shouldAskPermissions()) {
askPermissions();
}
}

Be aware that the solution:
<application ...
android:requestLegacyExternalStorage="true" ... >
Is temporary, sooner or later your app should be migrated to use Scoped Storage.
In Android 10, you can use the suggested solution to bypass the system restrictions, but in Android 11 (R) it is mandatory to use scoped storage, and your app might break if you kept using the old logic!
This video might be a good help.

Android 10 (API 29) introduces Scoped Storage. Changing your manifest to request legacy storage is not a long-term solution.
I fixed the issue when I replaced my previous instances of Environment.getExternalStorageDirectory() (which is deprecated with API 29) with context.getExternalFilesDir(null).
Note that context.getExternalFilesDir(type) can return null if the storage location isn't available, so be sure to check that whenever you're checking if you have external permissions.
Read more here.

I'm experiencing the same. What I found is that if you go to Settings -> Application Manager -> Your App -> Permissions -> Enable Storage, it solves the issue.

It turned out, it was a stupid mistake since I had my phone still connected to the desktop PC and didn't realize this.
So I had to turn off the USB connection and everything worked fine.

I had the same problem on Samsung Galaxy Note 3, running CM 12.1. The issue for me was that i had
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="18"/>
and had to use it to take and store user photos. When I tried to load those same photos in ImageLoader i got the (Permission denied) error. The solution was to explicitly add
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
since the above permission only limits the write permission up to API version 18, and with it the read permission.

In addition to all answers, if the clients are using Android 6.0, Android added new permission model for (Marshmallow).
Trick: If you are targeting version 22 or below, your application will request all permissions at install time just as it would on any device running an OS below Marshmallow. If you are trying on the emulator then from android 6.0 onwards you need to explicitly go the settings->apps-> YOURAPP -> permissions and change the permission if you have given any.

Strangely after putting a slash "/" before my newFile my problem was solved. I changed this:
File myFile= new File(Environment.getExternalStorageDirectory() + "newFile");
to this:
File myFile= new File(Environment.getExternalStorageDirectory() + "/newFile");
UPDATE:
as mentioned in the comments, the right way to do this is:
File myFile= new File(Environment.getExternalStorageDirectory(), "newFile");

I had the same problem and none of suggestions helped. But I found an interesting reason for that, on a physical device, Galaxy Tab.
When USB storage is on, external storage read and write permissions don't have any effect.
Just turn off USB storage, and with the correct permissions, you'll have the problem solved.

I would expect everything below /data to belong to "internal storage". You should, however, be able to write to /sdcard.

Change a permission property in your /system/etc/permission/platform.xml
and group need to mentioned as like below.
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE">
<group android:gid="sdcard_rw" />
<group android:gid="media_rw" />
</uses-permission>

I had the same error when was trying to write an image in DCIM/camera folder on Galaxy S5 (android 6.0.1) and I figured out that only this folder is restricted. I simply could write into DCIM/any folder but not in camera.
This should be brand based restriction/customization.

Maybe the answer is this:
on the API >= 23 devices, if you install app (the app is not system app), you should check the storage permission in "Setting - applications", there is permission list for every app, you should check it on! try

To store a file in a directory which is foreign to the app's directory is restricted above API 29+. So to generate a new file or to create a new file use your application directory like this :-
So the correct approach is :-
val file = File(appContext.applicationInfo.dataDir + File.separator + "anyRandomFileName/")
You can write any data into this generated file !
The above file is accessible and would not throw any exception because it resides in your own developed app's directory.
The other option is android:requestLegacyExternalStorage="true" in manifest application tag as suggested by Uriel but its not a permanent solution !

When your application belongs to the system application, it can't access the SD card.

keep in mind that even if you set all the correct permissions in the manifest:
The only place 3rd party apps are allowed to write on your external card are "their own directories"
(i.e. /sdcard/Android/data/)
trying to write to anywhere else: you will get exception:
EACCES (Permission denied)

Environment.getExternalStoragePublicDirectory();
When using this deprecated method from Android 29 onwards you will receive the same error:
java.io.FileNotFoundException: open failed: EACCES (Permission denied)
Resolution here:
getExternalStoragePublicDirectory deprecated in Android Q

In my case I was using a file picker library which returned the path to external storage but it started from /root/. And even with the WRITE_EXTERNAL_STORAGE permission granted at runtime I still got error EACCES (Permission denied).
So use Environment.getExternalStorageDirectory() to get the correct path to external storage.
Example:
Cannot write: /root/storage/emulated/0/newfile.txt
Can write: /storage/emulated/0/newfile.txt
boolean externalStorageWritable = isExternalStorageWritable();
File file = new File(filePath);
boolean canWrite = file.canWrite();
boolean isFile = file.isFile();
long usableSpace = file.getUsableSpace();
Log.d(TAG, "externalStorageWritable: " + externalStorageWritable);
Log.d(TAG, "filePath: " + filePath);
Log.d(TAG, "canWrite: " + canWrite);
Log.d(TAG, "isFile: " + isFile);
Log.d(TAG, "usableSpace: " + usableSpace);
/* Checks if external storage is available for read and write */
public boolean isExternalStorageWritable() {
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
return true;
}
return false;
}
Output 1:
externalStorageWritable: true
filePath: /root/storage/emulated/0/newfile.txt
isFile: false
usableSpace: 0
Output 2:
externalStorageWritable: true
filePath: /storage/emulated/0/newfile.txt
isFile: true
usableSpace: 1331007488

I am creating a folder under /data/ in my init.rc (mucking around with the aosp on Nexus 7) and had exactly this problem.
It turned out that giving the folder rw (666) permission was not sufficient and it had to be rwx (777) then it all worked!

The post 6.0 enforcement of storage permissions can be bypassed if you have a rooted device via these adb commands:
root#msm8996:/ # getenforce
getenforce
Enforcing
root#msm8996:/ # setenforce 0
setenforce 0
root#msm8996:/ # getenforce
getenforce
Permissive

i faced the same error on xiaomi devices (android 10 ). The following code fixed my problem.
Libraries: Dexter(https://github.com/Karumi/Dexter) and Image picker(https://github.com/Dhaval2404/ImagePicker)
Add manifest ( android:requestLegacyExternalStorage="true")
public void showPickImageSheet(AddImageModel model) {
BottomSheetHelper.showPickImageSheet(this, new BottomSheetHelper.PickImageDialogListener() {
#Override
public void onChooseFromGalleryClicked(Dialog dialog) {
selectedImagePickerPosition = model.getPosition();
Dexter.withContext(OrderReviewActivity.this) .withPermissions(Manifest.permission.READ_EXTERNAL_STORAGE)
.withListener(new MultiplePermissionsListener() {
#Override
public void onPermissionsChecked(MultiplePermissionsReport report) {
if (report.areAllPermissionsGranted()) {
ImagePicker.with(OrderReviewActivity.this)
.galleryOnly()
.compress(512)
.maxResultSize(852,480)
.start();
}
}
#Override
public void onPermissionRationaleShouldBeShown(List<PermissionRequest> list, PermissionToken permissionToken) {
permissionToken.continuePermissionRequest();
}
}).check();
dialog.dismiss();
}
#Override
public void onTakePhotoClicked(Dialog dialog) {
selectedImagePickerPosition = model.getPosition();
ImagePicker.with(OrderReviewActivity.this)
.cameraOnly()
.compress(512)
.maxResultSize(852,480)
.start();
dialog.dismiss();
}
#Override
public void onCancelButtonClicked(Dialog dialog) {
dialog.dismiss();
}
});
}

In my case the error was appearing on the line
target.createNewFile();
since I could not create a new file on the sd card,so I had to use the DocumentFile approach.
documentFile.createFile(mime, target.getName());
For the above question the problem may be solved with this approach,
fos=context.getContentResolver().openOutputStream(documentFile.getUri());
See this thread too,
How to use the new SD card access API presented for Android 5.0 (Lollipop)?

I Use the below process to handle the case with android 11 and targetapi30
As pre-created file dir as per scoped storage in my case in root dir files//<Image/Video... as per requirement>
Copy picked file and copy the file in cache directory at the time of picking from my external storage
Then at a time to upload ( on my send/upload button click) copy the file from cache dir to my scoped storage dir and then do my upload process
use this solution due to at time upload app in play store it generates warning for MANAGE_EXTERNAL_STORAGE permission and sometimes rejected from play store in my case.
Also as we used target API 30 so we can't share or forward file from our internal storage to app

2022 Kotlin way to ask permission:
private val writeStoragePermissionResult =
registerForActivityResult(ActivityResultContracts.RequestMultiplePermissions()) { permissions ->}
private fun askForStoragePermission(): Boolean =
if (hasPermissions(
requireContext(),
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE
)
) {
true
} else {
writeStoragePermissionResult.launch(
arrayOf(
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE,
)
)
false
}
fun hasPermissions(context: Context, vararg permissions: String): Boolean = permissions.all {
ActivityCompat.checkSelfPermission(context, it) == PackageManager.PERMISSION_GRANTED
}

Android: mkdirs()/mkdir() on external storage returns false

I'm driven crazy with this:
Log.d("STATE", Environment.getExternalStorageState());
File f = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM), "work_data");
Log.d("PATH", f.getAbsolutePath());
if (!f.exists()) {
Log.d("MAKE DIR", f.mkdirs() + "");
}
The output log looks like this:
STATE mounted
PATH /mnt/sdcard/DCIM/work_data
MAKE DIR false
I made sure to add the correct permission:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
But I don't know why it could not create the folder. I also used mkdir() step by step but the result is the same. Please help me. I have googled so much and spent at least 2 days on this stupid thing. Thanks for your help!!
EDITING:
Sorry everyone! I had added <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> in <application> tag. this was my mistake! But thank you all for reply.

I got the same problem,and I am sure I had put the permission tag in the right place,but mkdirs didn't work yet, my system is Android 6.0, I resolve it now , you can check as below:
make sure your put the permission tag in .
open "setting/application" in your phone,check your application's permission(I found the permission in my manifest statement is not here),open the switch of the permission like this.(I found it is closed in default which make "mkdirs" failed)

I have had the same problem and I have searched everything for a week trying to find the answer. I think I found it and I think it's ridiculously easy, you have to put the uses-permission statement in the right place...
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.company.name"
android:versionCode="1"
android:versionName="0.2">
<uses-sdk android:minSdkVersion="8" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
When I had it inside the <application></application> section it did not work.

I know this is an old post but perhaps my answer can help somebody.
After several days dealing with this problem I have realized that while the phone is connected to the PC, which it turns to be always during development, the SD card is not available. Thus making to fail any attempt to create a directory or file over it.
To make it "easier" it seemed to behave differently depending of the telephone under test.
I know it can sound quite a silly problem, but it cost a lot of time that maybe some other can save.

Applicable only if your targetSdkVersion is 29 or above
Environment.getExternalStorageDirectory() is deprecated in API level 29.
To get the same functionality use this line
File mediaStorageDir = context.getExternalFilesDir(null);
If you have checked all the possible errors then try this fix.
Already answered here - https://stackoverflow.com/a/61480077/7764015

add this line of code in OnCreate()
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);

Might be it's too late for answer but if you already allowed R/W permission(Runtime Permission too) and still doesn't work add this below mentioned line in your AndroidManifest.xml
<application
........
........
android:requestLegacyExternalStorage="true">
Note: this must required if you'r targeting Android 10+

mkdirs() only returns true if the directory was created. If it is in place already, it should return false. So I would bet this directory already exists.

<application
.....
android:requestLegacyExternalStorage="true">
work well.

I had the same issue, and I just wanted to share my fix.
as per android
Beginning with Android 4.4, reading or writing files in your app's private directories does not require the READ_EXTERNAL_STORAGE or WRITE_EXTERNAL_STORAGE permissions.
So you can declare the permission should be requested only on the lower versions of Android by adding the maxSdkVersion attribute:
<uses-permission
android:name="android.permission.WRITE_EXTERNAL_STORAGE"
android:maxSdkVersion="18" />
but maxSdkVersion is the issue, I just removed it and now it works.

put this
Log.d("MAKE DIR", f.mkdir() + "");
instead of
Log.d("MAKE DIR", f.mkdirs() + "");
or try this
String s=Environment.getExternalStorageDirectory().toString()+"/";
File f = new File(s+"DCIM/work_data");

Your code is working fine for me.There is no any thing wrong in your code.
Just if you are making one directory use f.mkdir() instead of f.mkdirs()
You can see your folder in mnt => Sd card => DCIM => work_data

If you have android 6.0 and more, make sure your target sdk in gradle file less than 22:
targetSdkVersion 22
or you need to implement run time permissions.

This might help someone in the future.
the problem might also be that you write the address "/File/Address/" instead you should write
File.separator + "File" + File.separator + "Address" + File.separator
This is such a small and stupid thing but this worked for me after wasting hours of my time.

If you're targeting Android api 29 then add this in your AndroidManifest.xml
<application android:requestLegacyExternalStorage="true">

I tried to make a set of subfolders in external storage 'Test/Test1/Test2' when mkdirs() kept returning false. Turns out that 'Test' is either a reserved word for a folder in the external storage root. This was on a Motorola G (XT1541) and may apply to other devices as well.

For new devices, you have to ask user permission.
You can do that like this before create your file:
boolean hasPermission = (ContextCompat.checkSelfPermission(MainActivity.this,
Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED);
if (!hasPermission) {
//ask permission
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
REQUEST_WRITE_STORAGE);
}
else {
//you have permission, create your file
}
After user's action, you can handle result.
#Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode)
{
case 1: {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED)
{
//you have permission, create your file
//reload my activity with permission granted or use the features what required the permission
} else
{
Toast.makeText(MainActivity.this, "The app was not allowed to write to your storage. Hence, it cannot function properly. Please consider granting it this permission", Toast.LENGTH_LONG).show();
}
}
}
}