添加依賴

compile 'com.android.support:recyclerview-v7:25.3.0'

然后就可以在布局文件里用RecyclerView控件了

• RecyclerView類是ViewGroup的子類，每一個列表項(xiàng)都是作為一個view子對象顯示的
  RecyclerView負(fù)責(zé)回收和定位屏幕上子項(xiàng)的View
  定位是通過LayoutManager來實(shí)現(xiàn)的

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

• adapter是控制器對象，從模型層獲取數(shù)據(jù)，然后提供給recyclerView顯示

mRecyclerView.setAdapter(mAdapter);

• adapter還負(fù)責(zé)創(chuàng)建必要的ViewHolder,綁定ViewHolder與模型層數(shù)據(jù)
  適配器就在于把模型層數(shù)據(jù)（crimes）與視圖層（ViewHolder）適配然后在適配進(jìn)RecylerView中

• FindViewById(int)是耗時又耗內(nèi)存的操作
  ViewHolder起到了保存FindViewById方法的成果的作用，大大減少的消耗

CrimeAdapter

public class CrimeAdapter extends RecyclerView.Adapter<CrimeHolder>{

        private List<Crime> mCrimes;

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

        @Override
//獲取單項(xiàng)布局
        public CrimeHolder onCreateViewHolder(ViewGroup parent,int viewType)
        {
            LayoutInflater layoutInflater=LayoutInflater.from(getActivity());
            View view=layoutInflater.inflate(R.layout.list_item_crime,parent,false);
            return new CrimeHolder(view);
        }

        @Override
//將單項(xiàng)布局的控件用數(shù)據(jù)來配對填充
        public void onBindViewHolder(CrimeHolder holder,int position)
        {
            Crime crime=mCrimes.get(position);
            holder.bindHolder(crime);
        }

        @Override
//獲取總項(xiàng)數(shù)
        public int getItemCount(){
            return mCrimes.size();
        }
    }
}

• ViewHolder的作用是存下并加載列表項(xiàng)的布局，所以在其構(gòu)造函數(shù)中要傳入布局文件，也可以在它構(gòu)造的時候綁定監(jiān)聽事件
  CrimeHolder

public class CrimeHolder extends RecyclerView.ViewHolder
                 implements View.OnClickListener{
        private Crime mCrime;
        public TextView mTitleTextView;
        public TextView mDateTextView;
        public CheckBox mCheckBox;
        public CrimeHolder(View itemView){
            super(itemView);
//給列表項(xiàng)添加監(jiān)聽器也可以給列表項(xiàng)里的控件加
            itemView.setOnClickListener(this);
            mTitleTextView=(TextView)itemView.findViewById(R.id.title_text);
            mDateTextView=(TextView)itemView.findViewById(R.id.date_text);
            mCheckBox=(CheckBox)itemView.findViewById(R.id.check_box);
        }

        @Override
        public void onClick(View v){
            Toast.makeText(getActivity(),mCrime.getTitle()+"clicked!",Toast.LENGTH_SHORT).show();
        }
        //把綁定的代碼寫在viewHolder里然后在adapter里調(diào)用該方法更好
        public void bindHolder(Crime crime)
        {
            mCrime=crime;
            mTitleTextView.setText(mCrime.getTitle());
            mDateTextView.setText(mCrime.getDate().toString());
            mCheckBox.setChecked(mCrime.getSolved());
        }
    }

因?yàn)镃rimeListActivity和CrimeActivity都是管理一個Fragment的Activity，而且用的是同樣的布局，所以可以寫一個抽象類來封裝提交fragment事務(wù)的操作
因?yàn)楣芾淼氖遣煌膄ragment所以需要讓Activity重寫創(chuàng)建fragment的部分

public abstract class SingleFragmentActivity extends FragmentActivity{
    //不能用private因?yàn)橐谧宇惱锶?shí)現(xiàn)嘛
    protected abstract Fragment createNewFragment();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_crime);

        FragmentManager fragmentManager=getSupportFragmentManager();
        Fragment fragment=fragmentManager.findFragmentById(R.id.fragment_container);

        if(fragment==null){
            fragment=createNewFragment();
            fragmentManager.beginTransaction().add(R.id.fragment_container,fragment).commit();
       }
    }
}

CrimeListFragment的完整代碼

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


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
    {
        View view=inflater.inflate(R.layout.crimelist_recycleview,container,false);
        mRecyclerView=(RecyclerView)view.findViewById(R.id.crimes_recycle_list);
        mRecyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
        updateUI();
        return view;
    }

    private void updateUI(){
        CrimeLab crimeLab=CrimeLab.get(getActivity());
        mAdapter=new CrimeAdapter(crimeLab.getCrimes());
        mRecyclerView.setAdapter(mAdapter);
    }

    public class CrimeHolder extends RecyclerView.ViewHolder
                 implements View.OnClickListener{
        private Crime mCrime;
        public TextView mTitleTextView;
        public TextView mDateTextView;
        public CheckBox mCheckBox;
        public CrimeHolder(View itemView){
            super(itemView);
            itemView.setOnClickListener(this);
            mTitleTextView=(TextView)itemView.findViewById(R.id.title_text);
            mDateTextView=(TextView)itemView.findViewById(R.id.date_text);
            mCheckBox=(CheckBox)itemView.findViewById(R.id.check_box);
        }

        @Override
        public void onClick(View v){
            Toast.makeText(getActivity(),mCrime.getTitle()+"clicked!",Toast.LENGTH_SHORT).show();
        }
        //把綁定的代碼寫在viewHolder里然后在adapter里調(diào)用該方法更好
        public void bindHolder(Crime crime)
        {
            mCrime=crime;
            mTitleTextView.setText(mCrime.getTitle());
            mDateTextView.setText(mCrime.getDate().toString());
            mCheckBox.setChecked(mCrime.getSolved());
        }
    }

    public class CrimeAdapter extends RecyclerView.Adapter<CrimeHolder>{

        private List<Crime> mCrimes;

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

        @Override
        public CrimeHolder onCreateViewHolder(ViewGroup parent,int viewType)
        {
            LayoutInflater layoutInflater=LayoutInflater.from(getActivity());
            View view=layoutInflater.inflate(R.layout.list_item_crime,parent,false);
            return new CrimeHolder(view);
        }

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

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