用RecyclerView写的城市列表

分享一下城市列表的网格布局样式的demo，代码里面包括网格布局和竖直列表布局两种样式。
网格样式：

image.png

竖直列表样式：

image.png

1. 数据来源，本地的citylist.json城市数据源如下截取，放在新建的raw文件夹下面：

    [
      {
    "key": "A", 
    "list": [
        {
            "realname": "澳门", 
            "displayname": "澳门"
        }, 
        {
            "realname": "阿勒泰地区", 
            "displayname": "阿勒泰"
        },
        {
            "realname": "安康", 
            "displayname": "安康"
        }, 
        {
            "realname": "安庆", 
            "displayname": "安庆"
        }, 
        {
            "realname": "安顺", 
            "displayname": "安顺"
        }, 
        {
            "realname": "安阳", 
            "displayname": "安阳"
        }, 
        {
            "realname": "鞍山", 
            "displayname": "鞍山"
        }
        ]
      }
    ]
   

读取数据成String类型，在根据key关键词来解析数据。

public static String getFromRaw(Context context) {
    String result = "";
    try {
        InputStream in = context.getResources().openRawResource(
                R.raw.citylist);
        // 获取文件的字节数
        int lenght = in.available();
        // 创建byte数组
        byte[] buffer = new byte[lenght];
        // 将文件中的数据读到byte数组中
        in.read(buffer);
        result = new String(buffer,"utf-8");
        in.close();
    } catch (Exception e) {
        e.printStackTrace();
    }
    return result;
}

2.根据关键词Key来解析数据。设计的方法是一共多少个字母就有多少个Item。其中item里面在include一个RecyclerView的网格布 局和一个TextView来显示字母数据。所以在这里可以将解析的城市列表封装成一个Map数据，key对应的是字母，而value城市列表名则用list数组来封装，有多少个字母就新建对应的list来包含对应字母的所有城市名称,详见如下。（使用ArrayMap在数据量不大的情况下更省内存，性能更好）：

 //封装城市列表map集合
private ArrayMap<String, ArrayList<CityModel>> map = new ArrayMap<>();
//封装首字母list数组
private ArrayList<CityModel> nameSortsList = new ArrayList<>();

private void initData() {
    String json = FileUtil.getFromRaw(this);
    //解析数据
    try {
        JSONArray jsonArray = new JSONArray(json);
        for (int i = 0; i < jsonArray.length(); i++) {
            JSONObject jsonObject = jsonArray.getJSONObject(i);
            String nameSort = jsonObject.getString("key");
            JSONArray jsonCityArray = jsonObject.getJSONArray("list");
            CityModel cityModel = new CityModel();
            cityModel.setNameScort(nameSort);
            addMap(nameSort, jsonCityArray);
            nameSortsList.add(cityModel);//封装字母列表数据成list
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }
}
//添加到Map集合，key和解析的城市名组成的list相对应
private void addMap(String nameSort, JSONArray jsonCityArray) {
    if (!map.containsKey(nameSort)) {
        map.put(nameSort, new ArrayList<CityModel>());
    }

    for (int i = 0; i < jsonCityArray.length(); i++) {
        CityModel cityModel = new CityModel();
        try {
            JSONObject jsonCityObject = jsonCityArray.getJSONObject(i);
            String realName = jsonCityObject.getString("realname");
            String displayName = jsonCityObject.getString("displayname");
            cityModel.setCityName(displayName);
        } catch (JSONException e) {
            e.printStackTrace();
        }
        map.get(nameSort).add(cityModel);
    }
}

3.数据封装好后，再写Adapter，这里参照网上大神封装Adapter的方法，写一个AbsAdapter来绑定ViewHolder，在写一个BaseAdapter继承AbsAdapter来封装数据；ViewHolder封装成BaseViewHolder，里面将Item对应的布局传入形成对应的View，再将不同的View封装成SparseArray的View数组，在里面findViewById找到对应填写数据的子布局。三个基类代码就不贴了，详见Github源码: https://github.com/yangfang521314/ListCity_RecyclerView_Demo。

整体Item的Adapter：

public class ItemAdapter extends BaseAdapter<CityModel, ItemViewHolder> {
private RecyclerItemClickListener.OnItemClickListener onItemListener;
private ArrayMap<String, ArrayList<CityModel>> map;
private Context mContext;
private String style;

public ItemAdapter(Context context) {
    super(context);
    mContext = context;
}
@Override
protected ItemViewHolder createItemViewHolder(ViewGroup parent, int viewType) {
    ItemViewHolder viewHolder = new ItemViewHolder(parent, R.layout.item_city_layout);
    return viewHolder;
}
@Override
protected void bindCustomViewHolder(ItemViewHolder holder, int position) {
    holder.mNameSort.setText(data.get(position).getNameScort());
    if (map.containsKey(data.get(position).getNameScort())) {
        CityListAdapter cityAdapter = new CityListAdapter(mContext);
        cityAdapter.setData(map.get(data.get(position).getNameScort()));
        cityAdapter.setOnClickListener(onItemListener);
        if(style.equals("grid")){//网格布局
            holder.mRecyclerView.setLayoutManager(new GridLayoutManager(mContext, 4));
            holder.mRecyclerView.setAdapter(cityAdapter);
        }
        if(style.equals("list")){//竖直列表布局
            holder.mRecyclerView.setLayoutManager(new LinearLayoutManager(mContext,LinearLayoutManager.VERTICAL,false));
            holder.mRecyclerView.setAdapter(cityAdapter);
        }
    }
}

@Override
public void setData(List<CityModel> list) {
    data = list;
}

public void setCityName(ArrayMap<String, ArrayList<CityModel>> cityName) {
    this.map = cityName;
}

public void setOnItmeListener(RecyclerItemClickListener.OnItemClickListener clickListener) {
    this.onItemListener = clickListener;
}

public void setStyle(String style) {
    this.style = style;//分两种类型
  }
}

具体城市列表名的Adapter

public class CityListAdapter extends BaseAdapter<CityModel, ItemViewHolder> {
private RecyclerItemClickListener.OnItemClickListener onClickListener;

public CityListAdapter(Context context) {
    super(context);
}

@Override
protected ItemViewHolder createItemViewHolder(ViewGroup parent, int viewType) {
    return new ItemViewHolder(parent, R.layout.list_city_name);
}

@Override
protected void bindCustomViewHolder(final ItemViewHolder holder, final int position) {
    holder.mCityName.setText(data.get(position).getCityName());
    holder.mCityName.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onClickListener.onItemClick(holder.mCityName,position);
        }
    });
}

public void setOnClickListener(RecyclerItemClickListener.OnItemClickListener onClickListener) {
    this.onClickListener = onClickListener;
  }
}

ItemViewHolder：

public class ItemViewHolder extends BaseViewHolder {
public TextView mNameSort;
public RecyclerView mRecyclerView;
public TextView mCityName;

public ItemViewHolder(ViewGroup parent, @LayoutRes int resId) {
    super(parent, resId);
    mNameSort = getView(R.id.header_tv);
    mRecyclerView = getView(R.id.city_recyclerview);
    mCityName = getView(R.id.tv_cityname);
  }
}

4.主Activity代码：

public class GridCityActivity extends AppCompatActivity implements RecyclerItemClickListener.OnItemClickListener {

//封装城市列表数据
private ArrayMap<String, ArrayList<CityModel>> map = new ArrayMap<>();
//首字母数据
private ArrayList<CityModel> nameSortsList = new ArrayList<>();
private RecyclerView mRecyclerview;
private ItemAdapter adapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_city_list);
    Intent intent = getIntent();
    String style = intent.getStringExtra("style");
    initData();
    initGridRecy(style);
}

private void initGridRecy(String style) {
    mRecyclerview = (RecyclerView) findViewById(R.id.list_cyclerview);
    mRecyclerview.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false));
    adapter = new ItemAdapter(this);
    adapter.setData(nameSortsList);
    //列表和网格布局
    adapter.setCityName(map);
    adapter.setStyle(style);
    adapter.setOnItmeListener(this);//自定义监听方法
    mRecyclerview.setAdapter(adapter);
}
private void initData() {
    String json = FileUtil.getFromRaw(this);
    try {
        JSONArray jsonArray = new JSONArray(json);
        for (int i = 0; i < jsonArray.length(); i++) {
            JSONObject jsonObject = jsonArray.getJSONObject(i);
            String nameSort = jsonObject.getString("key");
            JSONArray jsonCityArray = jsonObject.getJSONArray("list");
            CityModel cityModel = new CityModel();
            cityModel.setNameScort(nameSort);
            addMap(nameSort, jsonCityArray);
            nameSortsList.add(cityModel);
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }
}

private void addMap(String nameSort, JSONArray jsonCityArray) {
    if (!map.containsKey(nameSort)) {
        map.put(nameSort, new ArrayList<CityModel>());
    }

    for (int i = 0; i < jsonCityArray.length(); i++) {
        CityModel cityModel = new CityModel();
        try {
            JSONObject jsonCityObject = jsonCityArray.getJSONObject(i);
            String realName = jsonCityObject.getString("realname");
            String displayName = jsonCityObject.getString("displayname");
            cityModel.setCityName(displayName);
        } catch (JSONException e) {
            e.printStackTrace();
        }
        map.get(nameSort).add(cityModel);
    }
}
@Override
public void onItemClick(View view, int position) {
    Toast.makeText(this, ((TextView) view).getText(), Toast.LENGTH_LONG).show();//自定义监听
  }
}

有错请指出，不吝赐教。
其他代码见GitHub：https://github.com/yangfang521314/ListCity_RecyclerView_Demo
如果你喜欢希望能顺手在Github点个star哦！谢谢！