强大的滚动控件——RecyclerView（一）基本用法

用前准备

打开app/build.gradle文件，在dependencies闭包中添加如下内容：

compile ‘com.android.support:recyclerview-v7:24.2.1’

如下

dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.1', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile 'com.android.support:appcompat-v7:24.2.1'
compile 'com.android.support:recyclerview-v7:24.2.1'
testCompile 'junit:junit:4.12'
}

XML文件

接下来是xml中的代码

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.sky.recyclerview.MainActivity">

<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
></android.support.v7.widget.RecyclerView>

</LinearLayout>

这里面没什么好说的，width和height要设置为match_parent

接下来是适配器，新建的FruitAdapter类，让这个适配器继承RecyclerView.Adapter，并将泛型指定为FruitAdapter.ViewHolder。其中ViewHolder是我们在FruitAdapter中定义的一个内部类，代码如下：

public class FruitAdapter extends RecyclerView.Adapter<FruitAdapter.ViewHolder> {
private List<Fruit> mFruitList;
static class ViewHolder extends RecyclerView.ViewHolder{

ImageView fruitImage;
TextView fruitName;

public ViewHolder(View itemView) {
super(itemView);
fruitImage = (ImageView) itemView.findViewById(R.id.fruit_image);
fruitName = (TextView) itemView.findViewById(R.id.fruit_name);

}
}

/**
* 用于把要展示的数据源传进来，并赋值给一个全局变量mFruitList，我们后续的操作都将在这个数据源的基础上进行。
* @param mFruitList
*/
public FruitAdapter(List<Fruit> mFruitList) {
this.mFruitList = mFruitList;
}

/**
* 用于创建ViewHolder实例的，并把加载出来的布局传入到构造函数当中，最后将viewholder的实例返回
* @param parent
* @param viewType
* @return
*/
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.fruit_item,parent,false);
ViewHolder viewHolder = new ViewHolder(view);
return viewHolder;
}

/**
* 用于对RecyclerView子项的数据进行赋值的，会在每个子项被滚动到屏幕内的时候执行，这里我们通过
* position参数得到当前项的Fruit实例，然后再将数据设置到ViewHolder的Imageview和textview当中即可，
* @param holder
* @param position
*/
@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();
}
}

接下来就是Activity.class了

其中一些重要的我都已经在代码中注释

public class MainActivity extends Activity {
private List<Fruit> fruitList = new ArrayList<>();

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initFruit();
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
/**
* 创建一个linearlayoutmaneger对象，并将他设置到recyclerview当中。layoutmanager用于指定
* recyclerview的布局方式，这里是线性布局的意思。可以实现和listview类似的效果。
*
* 接下来我们创建了Fruitadapter的实例，并将数据传进去
*/
LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(linearLayoutManager);
FruitAdapter adapter = new FruitAdapter(fruitList);
recyclerView.setAdapter(adapter);
}

private void initFruit() {
Fruit apple = new Fruit("Apple",R.mipmap.ic_launcher);
fruitList.add(apple);
Fruit banana = new Fruit("banana",R.mipmap.ic_launcher);
fruitList.add(banana);
Fruit oragen = new Fruit("orange",R.mipmap.ic_launcher);
fruitList.add(oragen);
Fruit watermelon = new Fruit("watermelon",R.mipmap.ic_launcher);
fruitList.add(apple);
Fruit pear = new Fruit("pear",R.mipmap.ic_launcher);
fruitList.add(pear);
Fruit grape = new Fruit("grape",R.mipmap.ic_launcher);
fruitList.add(grape);
Fruit pineapple = new Fruit("pineapple",R.mipmap.ic_launcher);
fruitList.add(pineapple);
Fruit strawberry = new Fruit("strawberry",R.mipmap.ic_launcher);
fruitList.add(strawberry);
Fruit cherry = new Fruit("cherry",R.mipmap.ic_launcher);
fruitList.add(cherry);
Fruit a = new Fruit("a",R.mipmap.ic_launcher);
fruitList.add(a);
Fruit b = new Fruit("b",R.mipmap.ic_launcher);
fruitList.add(b);
Fruit c = new Fruit("c",R.mipmap.ic_launcher);
fruitList.add(c);
Fruit d = new Fruit("d",R.mipmap.ic_launcher);
fruitList.add(d);
Fruit e = new Fruit("e",R.mipmap.ic_launcher);
fruitList.add(e);
Fruit f = new Fruit("f",R.mipmap.ic_launcher);
fruitList.add(f);
Fruit g = new Fruit("g",R.mipmap.ic_launcher);
fruitList.add(g);
Fruit h = new Fruit("h",R.mipmap.ic_launcher);
fruitList.add(h);

}
}

对了还有一个Fruit类我也顺便贴上来

/**
* Created by sky on 2017/2/23.
*/

public class Fruit {
private String name;
private int imageId;

public Fruit(String name, int imageId) {
this.name = name;
this.imageId = imageId;
}

public String getName() {
return name;
}

public int getImageId() {
return imageId;
}
}

github地址：https://github.com/skysunlei/RecyclerViewBeat

接下来关于RecyclerView我还会更新几篇进阶型的，有问题的可以留言我会积极回复的

效果图