初识RecyclerView

前言

这篇文章先讲述怎么去用，让小白可以根据步骤一步一步的用上RecyclerView，后续会出一系列的文章来分析优缺点，原理，嵌套。

第一步：

1、现在的项目基本上初创建的时候就包含support-v7的包了，如果没有的导入一下；
2、导入RecyclerView 的依赖包，通过File->Project Structure 导入

1.jpg

3、我们就可以开始在xml里面弄个RecyclerView来玩玩啦

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

4、初始化RecyclerView

    
    private RecyclerView mVertical;
    private RecyclerView mHorizontal;
    private RecyclerView mGrid;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mVertical = (RecyclerView) findViewById(R.id.vertical);
        mHorizontal = (RecyclerView) findViewById(R.id.horizontal);
        mGrid = (RecyclerView) findViewById(R.id.grid);
        initData();
        //ListView 效果
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        linearLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
        mVertical.setLayoutManager(linearLayoutManager);

        //horizontalScrollView效果
        LinearLayoutManager linearLayoutManager2 = new LinearLayoutManager(this);
        linearLayoutManager2.setOrientation(LinearLayoutManager.HORIZONTAL);
        mHorizontal.setLayoutManager(linearLayoutManager2);

        //GridView效果
        GridLayoutManager gridLayoutManager = new GridLayoutManager(this, 3);
        mGrid.setLayoutManager(gridLayoutManager);
    }

private void initData() {
        datas = new ArrayList<>();
        for (int i = 0; i < 102; i++) {
            datas.add("测试数据" + (i + 1));
        }
    }

private class Adapter extends RecyclerView.Adapter<RecyclerView.ViewHolder> {
        private List<String> testDatas;

        public Adapter(List<String> testDatas) {
            this.testDatas = testDatas;
        }

        @Override
        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
            View view = getLayoutInflater().inflate(R.layout.item_recycler, parent, false);
            return new RecyclerViewHolder(view);
        }

        @Override
        public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
            String data = testDatas.get(position);
            if (holder instanceof RecyclerViewHolder) {
                RecyclerViewHolder recyclerViewHolder = (RecyclerViewHolder) holder;
                recyclerViewHolder.getTextView().setText(data);
            }
        }

        @Override
        public int getItemCount() {
            return testDatas.size();
        }


        class RecyclerViewHolder extends RecyclerView.ViewHolder {
            private TextView textView;

            public RecyclerViewHolder(View itemView) {
                super(itemView);
                textView = (TextView) itemView.findViewById(R.id.item_textView);
            }

            public TextView getTextView() {
                return textView;
            }
        }
    }

看一下效果图

WechatIMG327.jpeg

很神奇的发现他没有ItemDecoration,就是这个干干净净的，清爽。
不过如果有需要的同学也别着急，可以有多种方式添加，这个留到下一篇文章讲解。