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I'm currently heavily modifying/rewriting an Android app and I have seen a very occasional crash along the following lines: a CursorAdapter method is called, it calls AbstractWindowedCursor#checkPosition(), and:

02-20 15:03:18.180 E/AndroidRuntime(17143): android.database.StaleDataException: Attempting to access a closed CursorWindow.Most probable cause: cursor is deactivated prior to calling this method.
02-20 15:03:18.180 E/AndroidRuntime(17143): at android.database.AbstractWindowedCursor.checkPosition(AbstractWindowedCursor.java:139)
02-20 15:03:18.180 E/AndroidRuntime(17143): at android.database.AbstractWindowedCursor.getLong(AbstractWindowedCursor.java:74)
02-20 15:03:18.180 E/AndroidRuntime(17143): at android.database.CursorWrapper.getLong(CursorWrapper.java:106)
02-20 15:03:18.180 E/AndroidRuntime(17143): at android.widget.CursorAdapter.getItemId(CursorAdapter.java:220)

The trouble is, we're not closing any Cursors. All our Cursors come from CursorLoaders and in turn are produced by a ContentProvider. We're passing the Cursor into each respective CursorAdapter from the LoaderCallbacks, we're registering the Cursor for notifications in the ContentProvider, we're notifying the ContentResolver from each insert(...), delete(...) and update(...) ... in short I can't find any reason why a Cursor would close while in use.

So: what are the other causes of a StaleDataException?

Andrew Wyld
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  • It's been a while since you asked, but... was there a FilterQueryProvider involved, by any chance? – Graham Borland May 09 '14 at 15:57
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    Hey Andrew! Were you able to figure out the solution ? – TheLittleNaruto Aug 25 '16 at 11:15
  • I don't think we ever definitively tracked this down. However, we did discover that using a `Cursor` from outside the adapter provoked this behaviour, even though (again) we never called `.close()` or any method that you'd think caused this. Since then, I've always implemented `ContentObserver` and `DataSetObserver` in a manner analogous to https://android.googlesource.com/platform/frameworks/base/+/master/core/java/android/widget/CursorAdapter.java (skip to the end) if I ever had to use a Cursor both inside and outside an adapter. – Andrew Wyld Aug 28 '18 at 15:28

2 Answers2

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If you are calling Cursor.changeCursor(newCursor), that will automatically close the old cursor for you. This can cause android.database.StaleDataException if anything is still trying to access the cursor.

Mike Bruce
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if you called Context.managedQuery() in android 4.0 and above, you should not call Cursor.close(), if you do so, StaleDataException will be thrown, you can modify you code as follow:

if(VERSION.SDK_INT < 14) {  
    cursor.close();  
}
exloong
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