File.listFiles returns null when it shouldn't

Question

I am trying to get list of files existing in the Phone Pictures folder (internal storage, no SDCard inserted) using this:

 File file = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
 File[] files = file.listFiles();

but files value is always being null. I also add this to AndroidManifest.xml

 <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

Any ideas will be much appreciated, thanks in advance.

`File file = new File(String.valueOf(Environment.getExternalStoragePublicDirectory( Environment.DIRECTORY_PICTURES ).getAbsoluteFile()));`. That is terrible code. Change to `File file = Environment.getExternalStoragePublicDirectory( Environment.DIRECTORY_PICTURES);` — greenapps, Feb 09 '17 at 10:24
What is the value of file.getAbsolutePath() using your code? — greenapps, Feb 09 '17 at 10:28
/storage/emulated/0/Pictures, is this the path to access the internal memory Pictures folder? — Yahya Hussein, Feb 09 '17 at 10:30

score 3 · Accepted Answer · answered Feb 09 '17 at 10:20

3

If you are targeting Android SDK >=23 you need to take permission at run-time.

https://developer.android.com/training/permissions/requesting.html

answered Feb 09 '17 at 10:20

Abhishek Aryan

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what permission do I need? WRITE_EXTERNAL_STORAGE? already tried that from code, nothing changed – Yahya Hussein Feb 09 '17 at 10:22
WRITE_EXTERNAL_STORAGE this permission in AndroidManifest.xml and take permission at run-time – Abhishek Aryan Feb 09 '17 at 10:36

score 1 · Answer 2 · answered Feb 09 '17 at 10:15

1

It returns null as Environment.getExternalStoragePublicDirectory will/is supposed to handle files from external storage like SD card..as you are stating no sd card is inserted

answered Feb 09 '17 at 10:15

Akshay

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From external storage indeed. But never from an SD card. – greenapps Feb 09 '17 at 10:19
What exactly is your requirement..??I assume you want to list pictures from internal storage assuming you mentioned no SD card – Akshay Feb 09 '17 at 10:20
The function name sais it all: from external storage. – greenapps Feb 09 '17 at 10:22

score 0 · Answer 3 · answered Feb 09 '17 at 12:07

As Abhishek Aryan suggested, I am using Android SDK >=23 so I had to obtain permissions using code:

  boolean grantedAll = ContextCompat.checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED;
if (!grantedAll)
   {
     ActivityCompat.requestPermissions(thisActivity,
            new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
            REQUEST_PERMISSIONS);
   }

File.listFiles returns null when it shouldn't

3 Answers3

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