android複習路之RecyclerView簡單的應用

之前接觸了RecyclerView學寫了一個簡單的demo效果就是實現美團頂部的側滑效果，今天就是隻是簡單的實現效果，不深入理解，明天深入理解RecyclerView，各種變換和操作。

MainActivity代碼：

public class MainActivity extends AppCompatActivity {
    private RecyclerView rv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        rv = (RecyclerView) findViewById(R.id.rv);
        initdata();
    }

    private void initdata() {


        /*
          初始化數據
         */
        List<Integer> datas = new ArrayList<>();
        for (int i = 0; i < 20; i++) {
            Resources rs = getResources();
            datas.add(rs.getIdentifier("ic_launcher", "mipmap", getPackageName()));
        }

        /*
         用來確定每一個item如何進行排列擺放
         LinearLayoutManager 相當於ListView的效果
         GridLayoutManager相當於GridView的效果
         StaggeredGridLayoutManager 瀑布流
         */
        rv.setLayoutManager(new StaggeredGridLayoutManager(2, StaggeredGridLayoutManager.HORIZONTAL));
        rv.addItemDecoration(new RecyclerView.ItemDecoration() {
            @Override
            public void getItemOffsets(Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
                //outRect.left = 10;
                //outRect.top = 10;
                //outRect.top = 10;
            }
        });
        rv.setAdapter(new LinearRecyclerView(this,datas));
    }
}

LinearRecyclerView類代碼：

public  class LinearRecyclerView extends RecyclerView.Adapter<LinearRecyclerView.MyViewHolder>{
    private Context context;
    private List<Integer> datas;
    public  LinearRecyclerView(Context context,List<Integer>datas){
        this.context=context;
        this.datas=datas;
    }

    @Override
    public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        View contentView =LayoutInflater.from(context).inflate(R.layout.item_layout,parent,false);
        MyViewHolder viewHolder=new MyViewHolder(contentView);
        return viewHolder;
    }

    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {
        holder.imageView.setImageResource(datas.get(position));
        holder.textView.setText("分類"+position);
    }

    @Override
    public int getItemCount() {

        return datas==null?0:datas.size();
    }


    public class MyViewHolder extends RecyclerView.ViewHolder{
        private ImageView imageView;
        private TextView textView;
        public MyViewHolder(View itemView) {
            super(itemView);
            imageView= (ImageView) itemView.findViewById(R.id.img);
            textView= (TextView) itemView.findViewById(R.id.tv);
        }
    }
}

主佈局xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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.zobject.linearrecyclerview.MainActivity">

    <android.support.v7.widget.RecyclerView
        android:layout_height="200dp"
        android:layout_width="match_parent"
        android:id="@+id/rv"
        >

    </android.support.v7.widget.RecyclerView>

</RelativeLayout>

item佈局xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="70dp"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >
    <ImageView
        android:id="@+id/img"
        android:layout_gravity="center"
        android:layout_width="60dp"
        android:layout_height="75dp"

        >
    </ImageView>>
    <TextView
        android:id="@+id/tv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center"
        android:textColor="#000000"
        android:text="nicaicai"
        >

    </TextView>

</LinearLayout>

代碼沒什麼說的都是基本的模版代碼，方便以後查看，下面是效果圖：