CODEWITHSUNDEEP
javaandroid
dlucci
dlucci

Reputation: 818

context.getExternalFilesDir(null) is null

I am trying to debug a problem I am having in my app. The issue is that getExternalFiles(dir) returns null in my android app but I am not sure why. I have the necessary permissions. This is a bug which exists on multiple devices and versions of android (2.3.5 and up). Let me know if you need any more information.

The line of code which is the problem is:

path = context.getExternalFilesDir(null) + "/database/mydata.db";

or

path = context.getFilesDir().getAbsolutePath() + "/database/mydata.db";

Thank you.

Upvotes: 2

Views: 11313

Answers (4)

Noor Hossain
Noor Hossain

Reputation: 1841

In my case the problem was in the context

context.getExternalFilesDir(null) + "/database/mydata.db";

I passed a global context, that obtain from a separate class _MyApplication. But I forgot to add it in the manifest. so, the solution was In the manifest :

<application
        android:name="._MyApplication"
        android:allowBackup="true" 
.......

Upvotes: 0

benchuk
benchuk

Reputation: 689

Could be permissions issue Try to add this as well:

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

Upvotes: 3

Ken Wolf
Ken Wolf

Reputation: 23279

context.getExternalFilesDir(null) returning null is a perfectly valid response.

From the docs:

Returns

The path of the directory holding application files on external storage. Returns null if external storage is not currently mounted so it could not ensure the path exists; you will need to call this method again when it is available.

http://developer.android.com/reference/android/content/Context.html#getExternalFilesDir(java.lang.String)

So it looks like the devices where it is failing have an external SD card that is currently not available (user has mounted it, removed it, etc.).

You will have to check for this case using something like Environment.getExternalStorageState() and handle accordingly if it's not there.

Upvotes: 4

Winston
Winston

Reputation: 1820

 String state = Environment.getExternalStorageState();
        if (Environment.MEDIA_MOUNTED.equals(state) || Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
            return true; 
        } 
        return false;

Upvotes: 3

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