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Access to the path ... is denied - Xamarin Android

I am trying to write an image to my android file system, however when trying to write the bytes, I get the above error.
I am running Visual Studio 2019 (as administrator) and targeting API Level 29
AndroidManifest.xml
My external storage permissions are present in my manifest file:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
And as per another suggestion I have added android:requestLegacyExternalStorage="true" in my application tag:
<application android:label="App Name" android:icon="#mipmap/launcher_foreground" android:extractNativeLibs="true" android:requestLegacyExternalStorage="true">
MainActivity.cs
Here I am requesting the permissions when the app starts and pressing allow on both prompts:
int requestPermissions = 0;
string cameraPermission = Android.Manifest.Permission.Camera;
string filePermission = Android.Manifest.Permission.WriteExternalStorage;
if (!(ContextCompat.CheckSelfPermission(this, cameraPermission) == (int)Permission.Granted) || !(ContextCompat.CheckSelfPermission(this, filePermission) == (int)Permission.Granted))
{
ActivityCompat.RequestPermissions(this, new String[] { cameraPermission, filePermission
}, requestPermissions);
}
SaveMedia.cs
I get the error on File.WriteAllBytes:
public string SavePickedPhoto(Stream file, string fileName)
{
var bytes = GetBytesFromStream(file);
string path = Path.Combine(Android.App.Application.Context.GetExternalFilesDir("").AbsolutePath + "PhotoDirectoryForApp";
if (!Directory.Exists(path))
{
try
{
Directory.CreateDirectory(path);
}
catch (Exception e)
{
}
}
Path.Combine(path, fileName);
try
{
File.WriteAllBytes(path, bytes);
}
catch (Exception ex)
{
}
return path;
}
I am at a bit of a loss on what to try next as to me it seems that I should have the necessary permissions to write a file to a folder on the device. I have also tried various locations to save to and methods of saving with the same result.
Thanks in advance

You are trying to write to a directory as you are throwing away the return value from Path.Combine :
Path.Combine(path, fileName);
Try:
~~~
path = Path.Combine(path, fileName);
~~~

android mkdirs not working

i need to save an image from camera on android.
i used the write external storage permission in manifest and i am using this code
File dir = new File(Environment.getExternalStorageDirectory(), "Test");
if (!dir.exists() || !dir.isDirectory())
dir.mkdirs();
String path = dir.getAbsolutePath();
Log.d(TAG, path); //log show the path
File file = new File(dir.getAbsolutePath() + "/Pic.jpg");
Log.d(TAG, file.getAbsolutePath()); //again path is shown here
outStream = new FileOutputStream(file);
outStream.write(bytes);
outStream.close();
Log.d(TAG, "onPictureTaken - wrote bytes: " + bytes.length); //fail here
} catch (FileNotFoundException e) {
Log.d(TAG, "not done"); //error is here (this exception is thrown)
} catch (IOException e) {
Log.d(TAG, "not");
} finally { }
i also tried mkdir() instead of mkdirs() same result.
any idea what went wrong in the code?
thanks

For those not as experienced like me. I fought this issue, lost hair for some time. I am targeting api 21 (for compatibility sake) and it worked on lollipop but on marshmallow it would not create the directory. I did have the "uses" permission in the manifest but it still would not work. Apparently in Marshmallow when you install with Android studio it never asks you if you should give it permission it just quietly fails, like you denied it. You must go into Settings, apps, select your application and flip the permission switch on.

Some one like me who was trying in Android10. Please use below API in manifest:
<application android:requestLegacyExternalStorage="true" ... >
...
</application>
Latest Update From Google:
After you update your app to target Android 11, the system ignores the requestLegacyExternalStorage flag.

Did you put
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
in your AndroidManifest? If you are using android M you must request user permission to write on sd, look here an example

IDIOT ME! i have used the Manifest Permission but when installed the app on phone i didnt grant permission for storage!... i understand a negative on this question... but i hope if someone else face the same..check your phone permission. sorry all for inconvenience.

you have created directory, not file. Create new file with following code
File file = new File(dir.getAbsolutePath() + "/Pic.jpg");
file.createNewFile()

if you are testing on android M, you should probably check Settings > App > Permission to see if permission to access storage is granted. This saved me.

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+

Starting from API 30 you can only write in your app-specific files
File dir = new File(context.getFilesDir(), "YOUR_DIR");
dir.mkdirs();
or in the external storage of your app Android/data
File dir = new File(myContext.getExternalFilesDir("FolderName"),"YOUR_DIR");
UPDATE
this answer provided another solution https://stackoverflow.com/a/65744517/8195076
UPDATE
another way is to grant this permission in manifest
<uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE" />
like this answer https://stackoverflow.com/a/66968986/8195076

Try this. Provide runtime permission for marshmallow it is perfectly work in my Application code :
private String getFilename(String strFileName) {
String filepath = Environment.getExternalStorageDirectory().getPath();
File fileBase = new File(filepath, "Test");
if (!fileBase.exists()) {
fileBase.mkdirs();
}
return (file.getAbsolutePath() + "/" + strFileName + file_exts[currentFormat]);
}
new File(getFilename(edt.getText().toString().trim()))

outputFile = new File(apkStorage + "/" + downloadFileName );
//Create Output file in Main File
//Create New File if not present
if (!outputFile.exists()) {
isExternalStorageWritable();
outputFile.getParentFile().mkdirs();
outputFile.createNewFile();
Log.e(TAG, "File Created");
OutputStream fos = new FileOutputStream(outputFile);//Get OutputStream for NewFile Location
InputStream fis = c.getInputStream();//Get InputStream for connection
byte[] buffer = new byte[1024];//Set buffer type
int len1 = 0;//init length
while ((len1 = fis.read(buffer)) >0) {
fos.write(buffer, 0, len1);//Write new file
}
//Close all connection after doing task
fos.close();
fis.close();
I wrote this code for creating a file, but it is not working in android 11

when writing code for android API 29 and above use the following permission in your application manifest (AndroidManifest.xml)
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE"/>
Adjust your code to read like the following
ActivityCompat.requestPermissions(this, new String[]
{
Manifest.permission.READ_EXTERNAL_STORAGE,
Manifest.permission.WRITE_EXTERNAL_STORAGE
},
PackageManager.PERMISSION_GRANTED);
StrictMode.VmPolicy.Builder builder = new StrictMode.VmPolicy.Builder();
StrictMode.setVmPolicy(builder.build());
file = new File(Environment.getExternalStorageDirectory().getPath(), "TestDirectory/Document/");
if (!file.exists()) {
try {
file.mkdirs();
} catch (Exception e) {
e.printStackTrace();
}
}

Unable to write image to Android SD Card (Permission Denied) [duplicate]

The following code which consists of downloading a file from a server and save it in the storage works fine when the device has an internal storage.
But when I tried it with a device with no internal storage, only with external storage I get the following exception.
java.io.filenotfoundexception open failed eacces (permission denied)
public void downloadFile(String dlUrl, String dlName) {
int count;
HttpURLConnection con = null;
InputStream is = null;
FileOutputStream fos = null;
try {
URL url = new URL( dlUrl );
con = (HttpURLConnection) url.openConnection();
con.setDoInput(true);
con.connect();
is = url.openStream();
String dir = Environment.getExternalStorageDirectory() + Util.DL_DIRECTORY;
File file = new File( dir );
if( !file.exists() ){
file.mkdir();
}
Util.LOG_W(TAG, "Downloading: " + dlName + " ...");
fos = new FileOutputStream(file + "/" + dlName);
byte data[] = new byte[1024];
while( (count = is.read(data)) != -1 ){
fos.write(data, 0, count);
}
Util.LOG_D(TAG, dlName + " Download Complete!");
} catch (Exception e) {
Util.LOG_E(TAG, "DOWNLOAD ERROR = " + e.toString() );
bServiceDownloading = false;
}
finally{
try {
if( is != null)
is.close();
if( fos != null)
fos.close();
if( con != null)
con.disconnect();
} catch (Exception e) {
Util.LOG_E(TAG, "CLOSE ERROR = " + e.toString() );
}
}
}
And in manifest file I has the following:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
Any suggestions what maybe the cause?
By the way Environment.getExternalStorageDirectory() returns /mnt/sdcard/ and file.mkdir() return false.

This attribute is "false" by default on apps targeting
Android 10 or higher.
<application android:requestLegacyExternalStorage="true" ... >
...
</application>

This problem seems to be caused by several factors.
Check#1
First add this permission in your manifest file and check if it is working:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application>
...
</application>
　　.....
Check#2:
If you are running on an emulator, check the properties to see if it has an SD card.
Check#3:
Disable file transfer from device to computer. If Enabled, the app wont be able to access the SD card.
Check#4:
If still not working, try the following:
String dir = Environment.getExternalStorageDirectory().getAbsolutePath()
For me the following worked:
The problem is that getExternalStorageDirectory returns /mnt/sdcard whereas I need the actual path of external storage which is /mnt/sdcard-ext and there is no API in android that can get me the absolute path of removable sdcard.
My solution was to hard code the directory as follows:
String dir = "/mnt/sdcard-ext" ;
Since the application is intended to work only on one device, the above did the job.
If you encounter the same problem, use an file explorer application to find out the name of the external directory and hard code it.

Use READ_EXTERNAL_STORAGE permission to read data from the device.

Did you try it on emulator? Check the properties if it has an SD card. I had the same problem, and it was because the emulator did not have an SD card. Check if yours has or not.

I had the same problem, and i solved it by disabling file transfer from device to computer.
Because if u enable file transfer, sd card is not accessible to debugging application.

try
Environment.getExternalStorageDirectory().getAbsolutePath()
and don't forget to add
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

Try using mkdirs instead of mkdir. If you are creating a directory path and parent doesn't exist then you should use mkdirs.

I suspect you are running Android 6.0 Marshmallow (API 23) or later. If this is the case, you must implement runtime permissions before you try to read/write external storage.
https://developer.android.com/training/permissions/requesting.html

i have done very silly mistake.
I have already put in AndroidManifest.xml
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
and also add permission in java file,as get permission pragmatically.
But there is mistake of Manifest.permission.READ_EXTERNAL_STORAGE.
Please use Manifest.permission.WRITE_EXTERNAL_STORAGE.
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, requestCode);

I had the same problem. I used the write and read permission in the manifest correctly , yet it didn't work! The solution was very silly: unplug your phone from the PC before running the application. It seems when your phone is connected as "Mass storage" to the PC, the application cannot access the external storage.

First in your manifest file declare permissions :
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE" />
now in header of application tag of manifest file :
android:requestLegacyExternalStorage="true"
now defines provider for your app in between tag of manifest file. as :
<provider
android:name="androidx.core.content.FileProvider"
android:authorities="${applicationId}.provider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="#xml/provider_path" />
</provider>
now create a folder xml in res folder like this :
now create a xml file provider_path.xml and copy below code in it :
<?xml version="1.0" encoding="utf-8"?>
<path>
<external-path
name="external_files"
path="." />
now in your activity :
String filename = null ;
URL url = null;
try {
url = new URL("http://websitename.com/sample.pdf");
filename = url.getPath();
filename = filename.substring(filename.lastIndexOf('/')+1);
} catch (MalformedURLException e) {
e.printStackTrace();
}
File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS)+"/"+filename);
if(file.exists()){
Uri uri = FileProvider.getUriForFile(context, "com.example.www"+".provider",file);
Intent i = new Intent(Intent.ACTION_VIEW);
i.setDataAndType(uri, "application/pdf");
i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP|Intent.FLAG_GRANT_READ_URI_PERMISSION);
context.startActivity(i);
}
else {
//download file here
new AlertDialog.Builder(context)
.setTitle("Information")
.setMessage("Do you want to download this file ?")
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
})
.setPositiveButton("Continue", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
DownloadManager.Request request = new DownloadManager.Request(Uri.parse(url+""));
request.setTitle(filename);
request.setMimeType("application/pdf");
request.allowScanningByMediaScanner();
request.setAllowedOverMetered(true);
request.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED);
request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS, filename);
DownloadManager downloadManager = (DownloadManager)context.getSystemService(DOWNLOAD_SERVICE);
downloadManager.enqueue(request);
}
}).show();
}

How to create folder in external storage?

This is what I tried.
private void createFolderInExternalStorage() {
String storagePath = System.getenv("SECONDARY_STORAGE");
Log.e("storagePath->",storagePath);
String path = "not available";
if (storagePath != null) {
Log.e("Path->", "" + storagePath);
File file = new File(storagePath.toString());
Log.e("readable->", "" + file.canRead());
Log.e("writable->", "" + file.canWrite());
Log.e("executable->", "" + file.canExecute());
dir = new File(storagePath + File.separator+etFolder.getText().toString());
if (!dir.exists()) {
dir.mkdirs();
Toast.makeText(this,"Folder "+etFolder.getText().toString()+" created",Toast.LENGTH_SHORT).show();
}else{
Toast.makeText(this,"Folder "+etFolder.getText().toString()+" already exists",Toast.LENGTH_SHORT).show();
}
path = dir.getPath();
} else {
Toast.makeText(this,"External Storage not available",Toast.LENGTH_SHORT).show();
}
tv.setText("External SDCARD path->" + path);
}
if Secondary storage is present then System.getenv("SECONDARY_STORAGE") return /storage/sdcard1 in my case but getting following:
03-21 12:02:26.827 14155-14155/com.think.teststorage E/readable->: false
03-21 12:02:26.827 14155-14155/com.think.teststorage E/writable->: false
03-21 12:02:26.828 14155-14155/com.think.teststorage E/executable->: false
Even in some devices getting the above status as true but folder creation fails.
I have added the permission:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
Suggestions are welcome.

You can use this code to create a folder.
File dir = new File("path/of/your/folder");
try{
if(dir.mkdir()) {
System.out.println("Folder created");
} else {
System.out.println("Folder is not created");
}
}catch(Exception e){
e.printStackTrace();
}
Add this permission also :
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
For further reference : see this link
Let me know if this works for you! :)

Use the following lines:
//Define the path you want
String path = Environment.getExternalStoragePublicDirectory(Environment.YOUR_DIRECTORY) + File.separator + "YourFolderName";
File file = new File(path);
if (!file.exists()) {
file.mkdirs();
}
YOUR_DIRECTORY is the directory where you want to create the folder, for example: DIRECTORY_DOCUMENTS, DIRECTORY_DOWNLOADS, DIRECTORY_PICTURES etc.
In your manifest should to add permission for write:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
Hope it help!

It is very simple and straightforward in android
`
File mFolder = new File(Environment.getExternalStorageDirectory(), "Folder_Name");
if (!mFolder.exists()) {
mFolder.mkdirs();
mFolder.setExecutable(true);
mFolder.setReadable(true);
mFolder.setWritable(true);
}
`
Also include required permissions in manifest
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

Just put these lines of code,
// create a File object for the parent directory
File wallpaperDirectory = new File("/sdcard/Wallpaper/");
// have the object build the directory structure, if needed.
wallpaperDirectory.mkdirs();
// create a File object for the output file
File outputFile = new File(wallpaperDirectory, filename);
// now attach the OutputStream to the file object, instead of a String representation
FileOutputStream fos = new FileOutputStream(outputFile);
and add require permission
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
Does not work on KitKat, external, physical sdcard ??
then use use
Environment.getExternalStorageDirectory().getPath();

how to read and write file on android 4.4?

I need to open gallery to show images in a specific directory,after a search I follow this
How to open gallery to show images in a specific directory
but the file.list returns me a null String[] on android 4.4
Than I write some test code:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listDirectory("ExternalStorageRoot",
Environment.getExternalStorageDirectory());
listDirectory(
"DCIM",
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM));
writeFileTest();
}
private void writeFileTest() {
String tag = "WriteTest";
String path = Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES).getAbsolutePath();
path = path + "/testFile.txt";
Log.d(tag, "path : " + path);
File file=new File(path);
FileOutputStream fileOutputStream;
try {
fileOutputStream = new FileOutputStream(file);
fileOutputStream.write("THIS IS A TEST LINE".getBytes());
fileOutputStream.flush();
fileOutputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
private void listDirectory(String tag, File f) {
Log.d(tag, "absolute path " + f.getAbsolutePath());
Log.d(tag, "is dir " + f.isDirectory());
Log.d(tag, "can read " + f.canRead());
Log.d(tag, "can write " + f.canWrite());
String[] fileNames = f.list();
Log.d(tag, fileNames == null ? "fileNames is null"
: "fileNames is not null");
if (fileNames != null) {
for (String string : fileNames) {
Log.d(tag, "file -- " + string);
}
}
}
I also add these lines in AndroidManifest.xml
<permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<permission android:name="android.permission.WRITE_MEDIA_STORAGE" />
TO:
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
EDIT:
I mess up the permission.It's Now every thing works fine!

4.4 changed the file permissions for the sd card. You can't write outside of your personal directory anymore. See also: http://www.androidcentral.com/kitkat-sdcard-changes