This line:
final FileOutputStream outputStream = new FileOutputStream(name);
results in a FileNotFoundException
with the message being /2ozjfFQzwv: open failed: EROFS (Read-only file system)
where "2ozjfFQzwv" is what I passed as the name of the file.
I have tried this with and without the WRITE_INTERNAL_STORAGE
permission. How do I create this file for writing?
Alternatively, I just want to be able to give an image to a new activity, and it is too large to serialize it in an extra. Is there an easier way than writing it to a file then reading from it again? All the questions on here seem to be about writing to an SD card, which I don't want to do because many people don't have SD card slots.
This question is related to
android
file
file-io
filesystems
android-file
To use internal storage for the application, you don't need permission, but you may need to use: File directory = getApplication().getCacheDir();
to get the allowed directory for the app.
Or:
getCashDir();
<-- should work
context.getCashDir();
(if in a broadcast receiver)
getDataDir();
<--Api 24
Here is simple sample from android developer.
Basically, you can write a file in the internal storage like this :
String FILENAME = "hello_file";
String string = "hello world!";
FileOutputStream fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
fos.write(string.getBytes());
fos.close();
As others have mentioned, app on Android can't write a file to any folder the internal storage but their own private storage (which is under /data/data/PACKAGE_NAME ).
You should use the API to get the correct path that is allowed for your app.
read this .
Google have restricted write access to the external sdcard. From API 19 there is a framework called Storage Access Framework which allows you the set up "contracts" to allow write access.
For further info:
Android - How to use new Storage Access Framework to copy files to external sd card
Adding
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
in manifest and using same as Martin:
path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES);
File file = new File(path, "/" + fname);
It worked.
If anyone getting this in unit/instrumentation testing, make sure you call getFilesDir()
on the app context, not the test context. i.e. use:
Context appContext = getInstrumentation().getTargetContext().getApplicationContext();
not
Context appContext = InstrumentationRegistry.getContext;
try using the permission of WRITE_EXTERNAL_STORAGE You should use that whether there is an external card or not.
This works well for me:
path = Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_MOVIES);
File file = new File(path, "/" + fname);
and places my files in the appropriate folder
Source: Stackoverflow.com