RecyclerView study

ListView를 개량하고 속도 등 성능을 개선했다고 해서 공부겸해서 적용해보았다. 예전에 구현했던 simplelist 대로  모델 클래스 T 를 처리하는 adapter를 매번 구현하지 않도록 generic으로 VIewHolder와 Adaper를  현하고, 사용하는 쪽에서는 ViewHolder만 구현한다.

RecyclerViewHolder<T>

package com.mdiwebma.base.simplelist;

import android.support.v7.widget.RecyclerView;
import android.view.View;

/**
 * @author djkim
 */
public abstract class RecyclerViewHolder<T> extends RecyclerView.ViewHolder {
   public RecyclerViewHolder(View itemView) {
      super(itemView);
   }

   abstract public void bindView(T data);

}

SimpleListRecyclerAdapter<T>

ArrayAdapter를 참조했고, SimpleListAdapter와 비슷하게 구현하려했으나 생성자에 어쩔 수 없이 R.layout.XXX를 파라미터로 받을 수 밖에 없었다. RecyclerView#ViewHolder는 이미 inflate된 view를 생성자에서 입력받아야 하기에 ViewHolder 내에서 inflate시킬 방법이 없었다. 

package com.mdiwebma.base.simplelist;

import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import android.app.Activity;
import android.support.annotation.LayoutRes;
import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.mdiwebma.base.R;
import com.mdiwebma.base.logging.Dlog;
import com.mdiwebma.base.utils.ViewUtils;

/**
 * @author djkim
 */
public class SimpleListRecyclerAdapter<T> extends RecyclerView.Adapter<RecyclerViewHolder<T>> {

   List<T> itemList = new ArrayList<>();

   private static final int VIEWTYPE_ITEM = 0;
   private static final int VIEWTYPE_MORE = 1;

   @NonNull
   final SimpleListController simpleListController;

   @LayoutRes
   final int viewHolderResouceId;
   @NonNull
   final Class<? extends RecyclerViewHolder<T>> viewHolderClass;

   RecyclerViewHolder<T> moreLoadingViewHolder;
   boolean notifyOnChange = true;
   Object lock = new Object();

   public SimpleListRecyclerAdapter(@NonNull SimpleListController simpleListController,
         Class<? extends RecyclerViewHolder<T>> viewHolderClass, int viewHolderResouceId) {
      this.simpleListController = simpleListController;
      this.viewHolderClass = viewHolderClass;
      this.viewHolderResouceId = viewHolderResouceId;
   }

   public void setMoreLoadingViewHolder(RecyclerViewHolder<T> moreLoadingViewHolder) {
      this.moreLoadingViewHolder = moreLoadingViewHolder;
   }

   @Override
   public RecyclerViewHolder<T> onCreateViewHolder(ViewGroup parent, int viewType) {
      LayoutInflater inflater = (LayoutInflater)parent.getContext().getSystemService(Activity.LAYOUT_INFLATER_SERVICE);

      if (viewType == VIEWTYPE_ITEM) {
         try {
            View itemView = inflater.inflate(viewHolderResouceId, null);
            return viewHolderClass.getDeclaredConstructor(View.class).newInstance(itemView);
         } catch (InstantiationException | IllegalAccessException | NoSuchMethodException
               | InvocationTargetException ex) {
            Dlog.assertException(ex);
            return null;
         }
      } else {
         if (moreLoadingViewHolder == null) {
            View itemView = inflater.inflate(R.layout.read_more_view, null);
            moreLoadingViewHolder = new DefaultMoreLoadingRecyclerViewHolder<T>(simpleListController, itemView);
         }
         return moreLoadingViewHolder;
      }
   }

   @Override
   public void onBindViewHolder(RecyclerViewHolder<T> holder, int position) {
      final int viewType = getItemViewType(position);
      if (viewType == VIEWTYPE_ITEM) {
         final T item = getItem(position);
         holder.bindView(item);
      } else { // VIEWTYPE_MORE
         holder.bindView(null);
      }
   }

   @Override
   public int getItemCount() {
      return itemList.size() + (simpleListController.hasMore() ? 1 : 0);
   }

   @Override
   public int getItemViewType(int position) {
      if (position < itemList.size()) {
         return VIEWTYPE_ITEM;
      }
      else {
         return VIEWTYPE_MORE;
      }
   }

   public void setNotifyOnChange(boolean notifyOnChange) {
      this.notifyOnChange = notifyOnChange;
   }

   public T getItem(int position) {
      return itemList.get(position);
   }

   public int getPosition(T item) {
      return itemList.indexOf(item);
   }

   /**
    * Adds the specified object at the end of the array.
    *
    * @param object The object to add at the end of the array.
    */
   public void add(T object) {
      synchronized (lock) {
         itemList.add(object);
      }
      if (notifyOnChange)
         notifyDataSetChanged();
   }

   /**
    * Adds the specified Collection at the end of the array.
    *
    * @param collection The Collection to add at the end of the array.
    */
   public void addAll(Collection<? extends T> collection) {
      synchronized (lock) {
         itemList.addAll(collection);
      }
      if (notifyOnChange)
         notifyDataSetChanged();
   }

   /**
    * Adds the specified items at the end of the array.
    *
    * @param items The items to add at the end of the array.
    */
   public void addAll(T... items) {
      synchronized (lock) {
         Collections.addAll(itemList, items);
      }
      if (notifyOnChange)
         notifyDataSetChanged();
   }

   /**
    * Inserts the specified object at the specified index in the array.
    *
    * @param object The object to insert into the array.
    * @param index The index at which the object must be inserted.
    */
   public void insert(T object, int index) {
      synchronized (lock) {
         itemList.add(index, object);
      }
      if (notifyOnChange)
         notifyDataSetChanged();
   }

   /**
    * Removes the specified object from the array.
    *
    * @param object The object to remove.
    */
   public void remove(T object) {
      synchronized (lock) {
         itemList.remove(object);
      }
      if (notifyOnChange)
         notifyDataSetChanged();
   }

   /**
    * Remove all elements from the list.
    */
   public void clear() {
      synchronized (lock) {
         itemList.clear();
      }
      if (notifyOnChange)
         notifyDataSetChanged();
   }

   /**
    * Sorts the content of this adapter using the specified comparator.
    *
    * @param comparator The comparator used to sort the objects contained
    *        in this adapter.
    */
   public void sort(Comparator<? super T> comparator) {
      synchronized (lock) {
         Collections.sort(itemList, comparator);
      }
      if (notifyOnChange)
         notifyDataSetChanged();
   }

   ///
   /// Default MoreLoadingViewHolder
   ///
   class DefaultMoreLoadingRecyclerViewHolder<T> extends RecyclerViewHolder<T> {

      @NonNull
      final SimpleListController simpleListController;

      @NonNull
      View loadingView;
      @NonNull
      View retryView;

      public DefaultMoreLoadingRecyclerViewHolder(@NonNull SimpleListController simpleListController1, View baseView) {
         super(baseView);
         this.simpleListController = simpleListController1;

         loadingView = baseView.findViewById(R.id.loading_layout);
         retryView = baseView.findViewById(R.id.retry_layout);

         baseView.findViewById(R.id.retry).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

               ViewUtils.setVisible(loadingView);
               ViewUtils.setGone(retryView);

               simpleListController.requestMoreLoading(true);
            }
         });
      }

      @Override
      public void bindView(Object item) {
         if (simpleListController.getMoreLoadingState() == SimpleListController.LoadingState.NORMAL) {
            ViewUtils.setVisible(loadingView);
            ViewUtils.setGone(retryView);

            simpleListController.requestMoreLoading(false);
         } else if (simpleListController.getMoreLoadingState() == SimpleListController.LoadingState.FAILED) {
            ViewUtils.setGone(loadingView);
            ViewUtils.setVisible(retryView);
         }
      }
   }
}

테스트 코드

TestRecyclerViewHolder

기존과 거의 비슷하다. inflate는 adapter에서 하기에 빠졌고, view초기화는 생성자에서 해야 한다. 

public static class TestRecyclerViewHolder extends RecyclerViewHolder<TestData> {

   public static final int LAYOUT = R.layout.test_view;
   TextView textView;
   ImageView imageView;
   TestData testData;

   public TestRecyclerViewHolder(View baseView) {
      super(baseView);
      textView = (TextView)baseView.findViewById(R.id.text_view);
      imageView = (ImageView)baseView.findViewById(R.id.image);
      baseView.setOnClickListener(new View.OnClickListener() {

         @Override
         public void onClick(View v) {
            ToastUtils.show(String.valueOf(testData.number));
         }
      });
   }

   @Override
   public void bindView(TestData item) {
      testData = item;
      textView.setText(String.valueOf(testData.number));
      ImageLoader.getInstance().displayImage(getUrl(testData.number), imageView, LearningHabitApp.getImageCacheOptions());
   }

}

RecyclerView초기화

귀찮지만 ViewHolder의 inlfate할 리소스 아이디를 넘겨야 한다.

simpleListController.setOnLoadingListener(new SimpleListController.OnLoadingListener() {
   @Override
   public void onLoading(boolean retry) {
      new MyTask(0, retry).setThreadName("requestLoading").execute().showProgressDialog(SplashActivity.this, 1);
   }

   @Override
   public void onMoreLoading(boolean retry) {
      new MyTask(lastData, retry).setThreadName("readMore").execute();
   }
});

adapter = new SimpleListRecyclerAdapter<>(simpleListController, TestRecyclerViewHolder.class, TestRecyclerViewHolder.LAYOUT);
listView.setAdapter(adapter);
LinearLayoutManager llm = new LinearLayoutManager(this);
//llm.setOrientation(LinearLayoutManager.HORIZONTAL);
listView.setLayoutManager(llm);

simpleListController.requestLoading(false);