RecyclerView之瀑布流

Fruit.Class  FruitAdapter.Class   activity_main.Xml和地址里的一样

public class MainActivity extends AppCompatActivity {

    List<Fruit> fruitlist = new ArrayList<Fruit>();
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initFruits();
        RecyclerView recyclerView = (RecyclerView) findViewById(recycler_view);

        //创建StaggeredGridLayoutManager 的实例,构造函数第一个参数 用于指定布局的列数,传入3表示会把布局分成3列
        //第二个参数用于指定布局的排列方向,传入StaggeredGridLayoutManager.VERTICAL表示会让布局纵向排列,

//最后把创建好的实例设置到recyclerView当中就可以了
        StaggeredGridLayoutManager layoutManager = new StaggeredGridLayoutManager

(3,StaggeredGridLayoutManager.VERTICAL);
        recyclerView.setLayoutManager(layoutManager);
        FruitAdapter adapter = new FruitAdapter(fruitlist);
        recyclerView.setAdapter(adapter);
        for(int i=0;i<fruitlist.size();i++){
Log.i("info",fruitlist.get(i).getFruitImageId()+" "+fruitlist.get(i).getFruitName());
}
}
void initFruits(){
for(int i=0;i<2;i++){
            Fruit apple = new Fruit(getRandomLengthName("Apple"),R.drawable.apple);
            fruitlist.add(apple);
            Fruit banana = new Fruit(getRandomLengthName("Banana"),R.drawable.banana);
            fruitlist.add(banana);
            Fruit cherry = new Fruit(getRandomLengthName("Cherry"),R.drawable.cherry);
            fruitlist.add(cherry);
            Fruit grape = new Fruit(getRandomLengthName("Grape"),R.drawable.grape);
            fruitlist.add(grape);
            Fruit mango = new Fruit(getRandomLengthName("Mango"),R.drawable.mango);
            fruitlist.add(mango);
            Fruit orange = new Fruit(getRandomLengthName("Orange"),R.drawable.orange);
            fruitlist.add(orange);
            Fruit pear = new Fruit(getRandomLengthName("Pear"),R.drawable.pear);
            fruitlist.add(pear);
            Fruit pineapple = new Fruit(getRandomLengthName("Pineapple"),R.drawable.pineapple);
            fruitlist.add(pineapple);
            Fruit strawberry = new Fruit(getRandomLengthName("Strawberry"),R.drawable.strawberry);
            fruitlist.add(strawberry);
            Fruit watermelon = new Fruit(getRandomLengthName("Watermelon"),R.drawable.watermelon);
            fruitlist.add(watermelon);
        }

    }
   //得到传入字符的随机数
    private String getRandomLengthName(String name) {
        Random random = new Random();
        int length = random.nextInt(20)+1; //创建1-20之间的随机数
        StringBuilder builder = new StringBuilder();
        for(int i=0;i<length;i++){
builder.append(name);
}
return builder.toString();

}



}

fruit.xml

<?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="wrap_content"
android:layout_margin="5dp"
android:orientation="vertical"
>

<ImageView
android:id="@+id/fruit_image"
android:src="@drawable/apple"
android:layout_gravity="center_horizontal"
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"
android:layout_marginTop="10dp"
android:text="苹果"
android:textColor="#000" />



</LinearLayout>