IssueTracker

This bug is in the Android Compatibility Package; I haven't tested it in Honeycomb with the real Fragment Manager. Steps to reproduce:

1. Create fragment objects A and B
2. Programmatically add fragment A to an activity
3. Replace fragment A with fragment B (using OP_REPLACE)
4. Pop the transaction from step 3 from the back stack
5. Repeat step 3

Symptom:

An IllegalStateException is thrown with the message "Fragment already added:...".

Cause:

The proximate cause of the problem is that fragment B's mImmediateActivity member is non-null. This is because in BackStackRecord.popFromBackStack, in BackStackRecord.java line 610, the code says "f.mImmediateActivity = mManager.mActivity;" rather than what I believe to be the correct code "old.mImmediateActivity = mManager.mActivity;" This appears to be a copy-and-paste bug caused by combining the OP_ADD and OP_REMOVE cases without realizing that the variable "f" refers to two different fragments in the two cases.

Workaround:

Instead of using OP_REPLACE, the calling code can remove fragment A and add fragment B in two separate operations. This avoids the erroneous code.