Chapter 8 Challenge Solutions

Android Programming (3rd Edition) 8. Displaying Lists with RecyclerView
13

Hi.

My solution is:

package com.example.ad.criminalintent;

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import java.util.List;

/**
 * Created by AD on 22.11.2017.
 */

public class CrimeListFragment extends Fragment {
    private RecyclerView mCrimeRecyclerView;
    private CrimeAdapter mAdapter;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_crime_list, container, false);

        mCrimeRecyclerView = (RecyclerView) view.findViewById(R.id.crime_recycler_view);

        mCrimeRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));

        updateUI();

        return view;
    }

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

        mAdapter = new CrimeAdapter(crimes);
        mCrimeRecyclerView.setAdapter(mAdapter);
    }

    private class CrimeHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
        private TextView mTitleTextView;
        private TextView mDateTextView;
        private Button mCallPoliceButton;
        private Crime mCrime;

        public CrimeHolder(LayoutInflater inflater, ViewGroup parent, int viewType) {
            super(inflater.inflate(viewType, parent, false));
            itemView.setOnClickListener(this);


            mTitleTextView = (TextView) itemView.findViewById(R.id.crime_title);
            mDateTextView = (TextView) itemView.findViewById(R.id.crime_date);
            if(viewType == R.layout.list_item_crime_requires_police) {
                mCallPoliceButton = (Button) itemView.findViewById(R.id.crime_callpolice);
                mCallPoliceButton.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {
                        Toast.makeText(getActivity(), mCrime.getTitle() + " Call Police!", Toast.LENGTH_SHORT).show();
                    }
                });
            }
        }

        public void bind(Crime crime) {
            mCrime = crime;
            mTitleTextView.setText(mCrime.getTitle());
            mDateTextView.setText(mCrime.getDate().toString());
        }

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

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

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

        @Override
        public int getItemViewType(int position) {
            if (mCrimes.get(position).isRequiresPolice()) {
                return R.layout.list_item_crime_requires_police;
            }

            return R.layout.list_item_crime;
        }

        @Override
        public CrimeHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            LayoutInflater layoutInflater = LayoutInflater.from(getActivity());

            return new CrimeHolder(layoutInflater, parent, viewType);
        }

        @Override
        public void onBindViewHolder(CrimeHolder holder, int position) {
            Crime crime = mCrimes.get(position);
            holder.bind(crime);
        }

        @Override
        public int getItemCount() {
            return mCrimes.size();
        }
    }
}
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