ListView与RecyclerView在在app应用非常广泛，相对于其他的view（button textview）来说比较复杂，接下来我将讲一下创建的流程以及两者的不同。

代码来自《第一行代码》

秋天到了，果园大丰收了，现在着急的事情，就是把水果收集好放进仓库里。

ListView

首先肯定要先把仓库准备好,腾一块地方出来，在布局中添加ListView。

 <?xml version="1.0" encoding="utf-8"?>

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     android:orientation="vertical"

     android:layout_width="match_parent"

     android:layout_height="match_parent">

     <ListView

         android:id="@+id/list_view"

         android:layout_width="match_parent"

         android:layout_height="match_parent" >

     </ListView>

 </LinearLayout>

把装水果的框子准备好，创建fruit_item布局。

 <?xml version="1.0" encoding="utf-8"?>

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     android:orientation="horizontal"

     android:layout_width="match_parent"

     android:layout_height="match_parent">

     <ImageView

         android:id="@+id/fruit_image"

         android:layout_width="wrap_content"

         android:layout_height="wrap_content" />

     <TextView

         android:id="@+id/fruit_name"

         android:layout_width="wrap_content"

         android:layout_height="wrap_content"

         android:layout_gravity="center_vertical"

         android:layout_marginLeft="10dp" />

 </LinearLayout>

主角登场啦，咱们的搬运工，创建类FruitAdapter。

他需要干什么呢？

先贴出源码，下面解释

    package com.example.listviewtest;

    import android.content.Context;

    import android.view.LayoutInflater;

    import android.view.View;

    import android.view.ViewGroup;

    import android.widget.ArrayAdapter;

    import android.widget.ImageView;

    import android.widget.TextView;

    import java.util.List;

    public class FruitAdapter extends ArrayAdapter<Fruit> {

        private int resourceId;

        public FruitAdapter(Context context, int textViewResourceId,

                            List<Fruit> objects) {

            super(context, textViewResourceId, objects);

            resourceId = textViewResourceId;

        }

        @Override

        public View getView(int position, View convertView, ViewGroup parent) {

            Fruit fruit = getItem(position); // 获取当前项的Fruit实例

            View view;

            ViewHolder viewHolder;

            if (convertView == null) {

                view = LayoutInflater.from(getContext()).inflate(resourceId, parent, false);

                viewHolder = new ViewHolder();

                viewHolder.fruitImage = (ImageView) view.findViewById (R.id.fruit_image);

                viewHolder.fruitName = (TextView) view.findViewById (R.id.fruit_name);

                view.setTag(viewHolder); // 将ViewHolder存储在View中

            } else {

                view = convertView;

                viewHolder = (ViewHolder) view.getTag(); // 重新获取ViewHolder

            }

            viewHolder.fruitImage.setImageResource(fruit.getImageId());

            viewHolder.fruitName.setText(fruit.getName());

            return view;

        }

        class ViewHolder {

            ImageView fruitImage;

            TextView fruitName;

        }

    }

搬运工的工作就是，返回一个装满水果的框框

拿到一个水果
找到一个框框
把水果放到框框里

把框框返回（结局自然回到里仓库）

拿到一个水果
```
 Fruit fruit = getItem(position);
```

找到一个框框

 View view;

 view = LayoutInflater.from(getContext()).inflate(resourceId, parent, false);

 ImageView fruitImage = (ImageView) view.findViewById(R.id.fruit_image)

 TextView fruitName = (TextView) view.findViewById(R.id.fruit_name)

把水果放到框框里

 viewHolder.fruitImage.setImageResource(fruit.getImageId());

 viewHolder.fruitName.setText(fruit.getName());

源码里面有两布优化，自己想想哦。

4.把框框返回

      return view;

RecylerView

还是老步骤，首先准备好仓库，在准备好框框

准备好仓库，腾一块地方出来

 <?xml version="1.0" encoding="utf-8"?>

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     android:layout_width="match_parent"

     android:layout_height="match_parent">

     <android.support.v7.widget.RecyclerView

         android:id="@+id/recycler_view"

         android:layout_width="match_parent"

         android:layout_height="match_parent" />

 </LinearLayout>

准备好框框，和上面一样

 <?xml version="1.0" encoding="utf-8"?>

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

     android:orientation="vertical"

     android:layout_width="match_parent"

     android:layout_height="wrap_content"

     android:layout_margin="5dp" >

     <ImageView

         android:id="@+id/fruit_image"

         android:layout_width="wrap_content"

         android:layout_height="wrap_content"

         android:layout_gravity="center_horizontal" />

     <TextView

         android:id="@+id/fruit_name"

         android:layout_width="wrap_content"

         android:layout_height="wrap_content"

         android:layout_gravity="left"

         android:layout_marginTop="10dp" />

 </LinearLayout>

请出我们更加聪明的搬运工了

先贴出源码，下面解释

package com.example.recyclerviewtest;

import android.support.v7.widget.RecyclerView;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.widget.ImageView;

import android.widget.TextView;

import android.widget.Toast;

import java.util.List;

public class FruitAdapter extends RecyclerView.Adapter<FruitAdapter.ViewHolder>{

    private List<Fruit> mFruitList;

    static class ViewHolder extends RecyclerView.ViewHolder {

        View fruitView;

        ImageView fruitImage;

        TextView fruitName;

        public ViewHolder(View view) {

            super(view);

            fruitView = view;

            fruitImage = (ImageView) view.findViewById(R.id.fruit_image);

            fruitName = (TextView) view.findViewById(R.id.fruit_name);

        }

    }

    public FruitAdapter(List<Fruit> fruitList) {

        mFruitList = fruitList;

    }

    @Override

    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.fruit_item, parent, false);

        final ViewHolder holder = new ViewHolder(view);

        holder.fruitView.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                int position = holder.getAdapterPosition();

                Fruit fruit = mFruitList.get(position);

                Toast.makeText(v.getContext(), "you clicked view " + fruit.getName(), Toast.LENGTH_SHORT).show();

            }

        });

        holder.fruitImage.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                int position = holder.getAdapterPosition();

                Fruit fruit = mFruitList.get(position);

                Toast.makeText(v.getContext(), "you clicked image " + fruit.getName(), Toast.LENGTH_SHORT).show();

            }

        });

        return holder;

    }

    @Override

    public void onBindViewHolder(ViewHolder holder, int position) {

        Fruit fruit = mFruitList.get(position);

        holder.fruitImage.setImageResource(fruit.getImageId());

        holder.fruitName.setText(fruit.getName());

    }

    @Override

    public int getItemCount() {

        return mFruitList.size();

    }

}

多了好多诶，其实，咱们聪明的搬运工制造了更多的工具，真是方便了好多。

现在搬运工只需要干两件事情了

找到一个水果

把水果放到框子里

  public void onBindViewHolder(ViewHolder holder, int position) {

      Fruit fruit = mFruitList.get(position);

      holder.fruitImage.setImageResource(fruit.getImageId());

      holder.fruitName.setText(fruit.getName());

  }

没错，只需要两部，其他的事情都靠聪明的搬运工制造出来的自动小车，送回到仓库了，是不是很酷。

现在创造出我们的工具

  static class ViewHolder extends RecyclerView.ViewHolder {

      View fruitView;

      ImageView fruitImage;

      TextView fruitName;

      public ViewHolder(View view) {

          super(view);

          fruitView = view;

          fruitImage = (ImageView) view.findViewById(R.id.fruit_image);

          fruitName = (TextView) view.findViewById(R.id.fruit_name);

      }

  }

这个工具记得他应该去仓库中腾出来的位置

再看看工具是怎么运作的

  @Override

  public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

      View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.fruit_item, parent, false);

      ViewHolder holder = new ViewHolder(view);

      return holder;

  }

首先他会和仓库联系一下，然后就会自动运回仓库啦。

秒客网

[安卓]ListView 与 RecyclerView的比较

ListView

RecylerView

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