recyclerViewAndroid首页投稿(暂停使用,暂停投稿)

RecyclerView.Adapter优化

2016-10-19  本文已影响219人  比萨u

缘由


最近项目我在项目中使用了RecyclerView代替了ListView。
其实,怎么说呢?就是懒,想少写代码,所以想研究一下能否简化一下.


分两种

  1. 第一种支持Butterknife(黄油刀)快速生成ViewHolder
    封装的父类RvBaseAdapter
public abstract class RvBaseAdapter<T, V extends RecyclerView.ViewHolder> extends RecyclerView.Adapter<V> {

   public List<T> data;
   public Context context;
 
   public RvBaseAdapter(List<T> data, Context context) {
       this.data = data;
       this.context = context;
   }

   @Override
   public int getItemCount() {
       return data == null ? 0 : data.size();
   }

   @Override
   public V onCreateViewHolder(ViewGroup parent, int viewType) {
       return onCreateViewHolder(LayoutInflater.from(context).inflate(getLayout(viewType), null));

   }
   /**
    * 获得布局文件
    * @return
    */
   protected abstract int getLayout(int viewType);
   /**
    * 创建一个ViewHolder
    * @param convertView View
    * @return
    */
   protected abstract V onCreateViewHolder(View convertView);
   /**
    * 绑定ViewHolder
    * @param holder   ViewHolder
    * @param position 位置
    */
   @Override
   public abstract void onBindViewHolder(V holder, int position);
}

子类使用实例方法

public class RvTestAdapter extends RvBaseAdapter<AdapterBean,RvTestAdapter.ViewHolder> {//要传入两个泛型进去
 
    public RvTestAdapter(List<AdapterBean> data, Context context) {
        super(data, context);
    }
    @Override
    protected int getLayout(int viewType) {                    //获得布局文件
        return R.layout.rv_adapter;
    }
    @Override
    protected ViewHolder onCreateViewHolder(View convertView) {//创建一个onCreateViewHolder
        return new ViewHolder(convertView);
    }
 
    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {//绑定onBindViewHolder
        holder.mT1.setText(data.get(position).getName());//绑定数据和控件之间
        ImageLoader.getInstance().displayCircleImage(context,R.mipmap.ic_launcher,holder.mI1);
        ...
    }
 
    static class ViewHolder extends RecyclerView.ViewHolder {//用插件快速生成的ViewHolder ,这样很方便
        @BindView(R.id.T_1)
        TextView mT1;
        @BindView(R.id.I_1)
        ImageView mI1;
        ViewHolder(View view) {
            super(view);
            ButterKnife.bind(this, view);
        }
    }
}
  1. 第二种情况不用写ViewHolder
    封装的父类RvBaseAdapter,里面封住了一个ViewHolder,动态查找控件
public abstract class RvAdapter<T> extends RecyclerView.Adapter<RvAdapter.ViewHolder> {
   public List<T> data;
   public Context context;
   public RvAdapter(List<T> data, Context context) {
       this.data = data;
       this.context = context;
   }
   @Override
   public int getItemCount() {
       return data == null ? 0 : data.size();
   }

   @Override
   public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
       View itemView = LayoutInflater.from(context).inflate(getLayout(viewType), null);
       ViewHolder holder = new ViewHolder(itemView, context);
       return holder;
   }
    
   /**
    * 获得布局文件
    *
    * @return
    */
   protected abstract int getLayout(int viewType);
    
   public class ViewHolder extends RecyclerView.ViewHolder {
       private HashMap<Integer, View> views;
       private Context context;

       public ViewHolder(View itemView, Context context) {
           super(itemView);
           this.views = new HashMap<>();//保存View的map
           this.context = context;
       }

       public <T extends View> T findById(int id) {             //查找控件
           View view = views.get(id);
           if (view == null) {
               view = itemView.findViewById(id);
               views.put(id, view);
           }
           return (T) view;
       }
       public RvAdapter.ViewHolder setText(int id, String txt) {//封装常用的设置数据方法
           TextView tv = findById(id);
           tv.setText(txt);
           return this;
       }
       public RvAdapter.ViewHolder setOnClickListener(int id, View.OnClickListener listener) {//设置监听
           View view = findById(id);
           view.setOnClickListener(listener);
           return this;
       }
  
       public RvAdapter.ViewHolder setImage(int id, String url) {
           ImageView img = findById(id);
           ImageLoader.getInstance().displayCircleImage(context, url, img);
           return this;
       }
      ···//这里可以扩展添加常用的方法
     
       public View getItemView() {
           return itemView;
       }
   }
}

子类使用实例方法

看起来是不是很简洁,窃喜~

public class RvTestAdapter extends RvAdapter<AdapterBean> {

   public RvTestAdapter(List<AdapterBean> data, Context context) {
       super(data, context);
   }

   @Override
   protected int getLayout(int viewType) {
       return R.layout.rv_adapter;
   }

   @Override
   public void onBindViewHolder(ViewHolder holder, final int position) {
       holder.setText(R.id.T_1, data.get(position).getName())
               .setText(R.id.T_1, data.get(position).getName())
               .setImage(R.id.I_1, data.get(position).getName())
               .setImage(R.id.I_1, data.get(position).getName())
               .setOnClickListener(R.id.T_2, new View.OnClickListener() {
                   @Override
                   public void onClick(View v) {
                       App.getInstance().showToast(data.get(position).getName());
                   }
               });
   }
}

结语:封装之后代码量显著减少,看上去很简洁

其实还可以在里面添加扩展功能 ==》

 public void remove(int position) {
       data.remove(position);
       notifyItemRemoved(position);
   }

   public void add(int position, T item) {
       data.add(position, item);
       notifyItemInserted(position);
   }
上一篇下一篇

猜你喜欢

热点阅读