Develop Reference

Is there a way to get 100% correct file extension in Android with scoped storage enabled?

I'm trying to implement a file sending functionality in my Android app (any files are allowed, and the files don't belong to my app). From the ACTION_OPEN_DOCUMENT I receive an InputStream, then I make a temp File object with the name I'm getting from ContentResolver's OpenableColumns.DISPLAY_NAME, and then send the file. The reason I do all of this is that I work with a 3rd party API which allows for File objects only.
But the OpenableColumns.DISPLAY_NAME doesn't guarantee that I get the file name with a file extension as stated in the docs. As far as I understand, there is no way to get the actual filename or physical path of a file with the Scoped Storage enforced in the newer versions of Android. Therefore, I have to check if a filename contains an extension, and if not - get the file's MIME type with ContentResolver and the most common extension for it using the MimeTypeMap. This approach feels to be not very reliable since I have to rely on both ContentResolver correctly determining the MIME type and MimeTypeMap retrieving the correct extension. Getting the extension is crucial at least because users should be able to download and open files on their PC from a desktop app.
So, is it possible to get a filename or at least file extension with a 100% guarantee with scoped storage enabled? Or maybe is there a more efficient way to handle my situation? I'd appreciate some help with this.

Try this method, it helped me:
public static String getFileName(Uri uri, Context context) {
String result = null;
if (uri.getScheme().equals("content")) {
Cursor cursor = context.getContentResolver().query(uri, null, null, null, null);
try {
if (cursor != null && cursor.moveToFirst()) {
result = cursor.getString(cursor.getColumnIndex(OpenableColumns.DISPLAY_NAME));
}
} finally {
cursor.close();
}
}
if (result == null) {
result = uri.getPath();
int cut = result.lastIndexOf('/');
if (cut != -1) {
result = result.substring(cut + 1);
}
}
return result;
}

Getting file path from uri on emulator

I want to get file path from Uri for a video. The following method works fine when testing with a real device, however, it fails (returns null) when testing on emulator.
public String getRealPathFromURI(Context context, Uri contentUri) {
Cursor cursor = null;
try {
String[] proj = {MediaStore.Video.Media.DATA};
cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
} catch (Exception e) {
e.printStackTrace();
} finally {
if (cursor != null) {
cursor.close();
}
}
return null;
}
What is the correct way of getting file path from uri on emulator?

The following method works fine when testing with a real device
Only on the the device that you tried, and only for the app that you tried. Particularly on Android 4.4+, your approach will be unreliable. That is because a Uri is not a file. On older versions of Android, for a Uri from the MediaStore, your approach might work.
Nowadays, do not attempt to get a file for a Uri. Consume the Uri as you are supposed to, using methods on ContentResolver to get an InputStream, the MIME type, etc.
What is the correct way of getting file path from uri on emulator?
There is none. There does not have to be a file path associated with a Uri, let alone a path that your app is able to access using Java file I/O.

As CommonsWare mentioned, an Uri is NOT a File. The general way to deal with Uri is to use an inputstream and save the content as a file (assuming that's what you are looking for). What i typically do is
get the metadata associated with the Uri (to get title / type of data / size)
get the content via an input stream to save it on the device as a file.
Take a look at the "Examine document metadata" and "get an inputstream" on this page: https://developer.android.com/guide/topics/providers/document-provider.html

GetRealPathFromUri always get null result

I'm trying to get real path from Uri(Of selected image from gallery) but This function returns always null value :
//Convert the image URI to the direct file system path of the image file
public String getRealPathFromURI(Uri contentUri) {
Cursor cursor = null;
try {
String[] proj = { MediaStore.Images.Media.DATA };
cursor = getActivity().getContentResolver().query(contentUri, proj, null, null, null);
cursor.moveToFirst();
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
return cursor.getString(column_index);
} finally {
if (cursor != null) {
cursor.close();
}
}
}

That's because the image you're selecting is not physically available on the device.
Images from gallery or other choose can come from different sources that does not provide a physical file, like a cloud storage for example.
Check this code here on how to open the Uri as a InputStream that can be used to create a copy of the file (or just read directly).
Android: Getting a file URI from a content URI?
edit:
I'm doing some extra research on it, apparently it also varies on how you request this Uri.
if you request it like this (which is the current preferred method as per Android guides):
i = new Intent(Intent.ACTION_GET_CONTENT);
i.addCategory(Intent.CATEGORY_OPENABLE);
i.setType("image/*");
startActivityForResult(i, REQUEST_STORAGE);
and it opens the KitKat style unified selector, if you choose an image from there, it will always return null. If you open the left-drawer menu, select the gallery (or a file browser), and pick an image from there, then, if it is a local file image, you will have the correct path.
on the other hand, if you request it like this (which is the old method):
i = new Intent(Intent.ACTION_PICK);
i.setType("image/*");
startActivityForResult(i, REQUEST_STORAGE);
it will directly open the Gallery, and again, if it is a local file image, you will have the correct path.
So yeah, I still don't believe there's a way to force local only, but at least you have more information to make an informed decision on your coding.

QuickOffice: get file uri from share function of quickoffice

In my app I can download a document (docx for example) and open it in QuickOffice. After edditing the document I use the save button and after succesfully saved it, I hit the share button and select my app so I can reupload it.
My problem is, is that the uri i got is not the usual uri you would expect as content://storage/map/file.docx or something like that. I get this from quickoffice:
content://com.quickoffice.android.quickcommon.FileContentProvider/zEV5qmvBJOg2GGWldHMJnNK687Ur6qLGbbMbxj0IxV9cDv2mN8XTGqRrEqU4KIfeZuQNMKMJ_eDx%0AN4YiNZwDShhb4E8%3D%0A
My question is, how can I turn this uri to the real path uri from the file (content://storage/map/file.docx for example)

There is no "real path".
A ContentProvider is welcome to store its content wherever it wants, which may not be a file (e.g., BLOB column in a database) and, even if it is, it may not be a file which you can access (e.g., internal storage for the app hosting the ContentProvider.
Please use the various methods on ContentResolver, such as openInputStream(), to access the contents of this provider.

Please use the following code. it worked fine for me.
public static String getContentName(ContentResolver resolver, Uri uri){
String[] ATTACHMENT_META_COLUMNS = {
OpenableColumns.DISPLAY_NAME,
OpenableColumns.SIZE
};
String name = "";
int size= 0;
Cursor metadataCursor = resolver.query(uri, ATTACHMENT_META_COLUMNS, null, null, null);
if (metadataCursor != null) {
try {
if (metadataCursor.moveToFirst()) {
name = metadataCursor.getString(0);
size = metadataCursor.getInt(1);
}
} finally {
metadataCursor.close();
}
}
if (name == null) {
name = uri.getLastPathSegment();
}
return name;
}

Resolving the path while recieving data from an external app

i am implementing the functionality to save file in my app which is being sent by some exteral application.
i have provided support for single and mulitple files. Provided handling for all kind of files.
But i am not able to handle the following scenario.
I view a file from an email client -> View it in QuickOffice -> Click on send -> Choose my app->Then click on save in my app.
In that i get the path in following wrapped in the exception
java.io.FileNotFoundException: /file:/data/data/com.qo.android.sp.oem/files/temp/Error.log: open failed: ENOENT (No such file or directory)
I have seen this post which is quite useful for handling uri which has content scheme
Get filename and path from URI from mediastore
Below is my code
Uri uri = (Uri) iterator.next();
if ("content".equals(uri.getScheme())) {
filePath = getFilePathFromContentUri(uri, hostAcitvity.getContentResolver());
}
else {
filePath = uri.getPath();
}
fileName = uri.getLastPathSegment();
fileSize = hostAcitvity.getContentResolver().openInputStream(uri).available();
Code for getFilePathFromContentUri
private String getFilePathFromContentUri(Uri selectedVideoUri, ContentResolver contentResolver)
{
String filePath;
String[] filePathColumn = { MediaColumns.DATA };
Cursor cursor = contentResolver.query(selectedVideoUri, filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
filePath = cursor.getString(columnIndex);
cursor.close();
return filePath;
}
Then i wrap the path in a FileInputStream which is throwing the above exception
Not able to resolve the file path properly. Is this the correct way of finding the path ?
cheers,
Saurav

I have seen this post which is quite useful for handling uri which has content scheme
That never worked reliably and will work even less reliably in the future.
Is this the correct way of finding the path ?
No, because there is no requirement that every Uri map to a path on a filesystem that you can access.
Use getInputStream() on ContentResolver to get an InputStream on the Uri, and consume the data that way.