Challenge 8: app crashes when trying to implement OnClickListeners

[sippolit]

I am able to get the rows to display just fine. I use a CardView for every fifth row to notify the user to call the cops. I want the user to be able to interact with the rows and display a toast with the crime title. Here are the important bits.

private class CrimeAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
    private List<Crime> mCrimes;

    public CrimeAdapter(List<Crime> crimes){
        mCrimes = crimes;
    }

    class PoliceHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

        private TextView mTitleTextView;
        private TextView mDateTextView;
        private Crime mCrime;

        public PoliceHolder(View itemView) {
            super(itemView);
            itemView.setOnClickListener(this);

            mTitleTextView = (TextView) itemView.findViewById(R.id.crime_title);
            mDateTextView = (TextView) itemView.findViewById(R.id.crime_date);
        }

        @Override
        public void onClick(View view) {
            Toast.makeText(getActivity(), mCrime.getTitle(), Toast.LENGTH_SHORT).show();
        }
    }
    class CrimeHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

        private TextView mTitleTextView;
        private TextView mDateTextView;
        private Crime mCrime;

        public CrimeHolder(View itemView) {
            super(itemView);
            itemView.setOnClickListener(this);

            mTitleTextView = (TextView) itemView.findViewById(R.id.crime_title);
            mDateTextView = (TextView) itemView.findViewById(R.id.crime_date);
        }

        @Override
        public void onClick(View view) {
            Toast.makeText(getActivity(), mCrime.getTitle(), Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
        Crime crime = mCrimes.get(position);

        switch (crime.isRequiresPolice()) {
            case 0 :
                ((PoliceHolder) holder).mTitleTextView.setText(crime.getTitle());
                ((PoliceHolder) holder).mDateTextView.setText(crime.getDate().toString());
                break;
            case 1 :
                ((CrimeHolder) holder).mTitleTextView.setText(crime.getTitle());
                ((CrimeHolder) holder).mDateTextView.setText(crime.getDate().toString());
                break;
        }

    }

[mhills]

Your calls to Toast.makeText use mCrime, but this is never set in either PoliceHolder or CrimeHolder. I assume you are getting a NullPointerException when you call mCrime.getTitle(). You should probably add a bind method similar to that in the book that accepts the instance of Crime the Holder represents.