Challenge:Crash about the delete crime

Android Programming (3rd Edition) 13. The Toolbar
1

After add several crimes and deleting crime(except the last one) app get a crash

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2

Please show your CrimeListFragment.java

    private void updateUI() {
        CrimeLab crimeLab = CrimeLab.getInstance(getActivity());
        List<Crime> crimes = crimeLab.getCrimes();

        if (mCrimeAdapter == null) {
            mCrimeAdapter = new CrimeAdapter(crimes);
            mCrimeRecyclerView.setAdapter(mCrimeAdapter);
        } else {
            mCrimeAdapter.setCrimes(crimes);  // Please check whether you update the data of the adapter
            mCrimeAdapter.notifyDataSetChanged();
        }

        // ......
    }
4

Thanks for your reminder.
I hava find the reason and fixed it; when deleting the item, need call notifyItemRemoved not notifyItemChanged;

private void updateUI(){
Log.d(TAG, “update ui”+mActionType);
CrimeLab crimeLab = CrimeLab.get(getActivity());
List crimes = crimeLab.getCrimes();
if(mAdapter == null){
mAdapter = new CrimeAdapter(crimes);
mCrimeRecycleView.setAdapter(mAdapter);
}else{
if(mLastAdapterClickPosition < 0){
mAdapter.notifyDataSetChanged();
}else{
Log.d(TAG, “notifyItemChanged—”+mLastAdapterClickPosition);
if(mActionType == “delete”){
mAdapter.notifyItemRemoved(mLastAdapterClickPosition);
mActionType = “”;
}else{
mAdapter.notifyItemChanged(mLastAdapterClickPosition);
}
mLastAdapterClickPosition = -1;
}
}
updateSubtitle();
}