Check whether a known document Uri exists in android phone storage

Question

I am fetching a document Uri from the server which points out to where the document (pdf or word) was initially stored in the phone storage at the time of upload. In my app, I would want to check if the document still exists in the user's phone storage (by checking if this uri is still valid) before downloading the document. How can I do this?I've tried multiple ways to no success. Please help. This is what I've already tried.

 Uri uri = Uri.parse("content://com.android.providers.downloads.documments/document/748");
            final File f = new File(uri.getPath());
           if (f.exists()){
                Log.d("File existence", "Yes, file exists");
            }else {
                Log.d("File does not exist", "so sorry");
            }

I also tried implementing this using ContentResolver as pointed out in this similar question but the method threw a security exception: querying the cursor requires manage documents permission which when added to the manifest also brought an error, that the permission is only used by system apps. Please help. I'm running the app in android 6.0.1 Thanks in advance

Just try to open an input stream for the uri. `getContext().getContentResolver().openInputStream(uri);`. — blackapps, Jan 05 '20 at 11:36
Of course you cannot use the File class for a content scheme uri. — blackapps, Jan 05 '20 at 11:37
But my proposal will only work if you still have a read permission. And you did not tell if you took a persistable permission at upload. — blackapps, Jan 05 '20 at 11:41

score 0 · Answer 1 · answered Jan 05 '20 at 06:09

0

Try this out :

getContext().getContentResolver().getPersistedUriPermissions().forEach( {element -> element.uri == yourUri});

answered Jan 05 '20 at 06:09

haresh

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Thanks for this. How do you implement this on Kitkat..coz forEach call requires API24 and above. My min is 19 (KitKat) – Ezra Raleigh Jan 05 '20 at 06:23
Look for this :https://stackoverflow.com/questions/42276329/unable-to-use-foreach-and-lambda-in-android-min-sdk-version-less-than-24 – haresh Jan 05 '20 at 06:27
does that helped you? – haresh Jan 05 '20 at 07:00
not really :(. Could you kindly kindly show a full implementation of this? – Ezra Raleigh Jan 05 '20 at 07:17

Check whether a known document Uri exists in android phone storage

1 Answers1