<!-- extend one of the Theme.AppCompat themes -->
<style name="Theme.MyTheme" parent="Theme.AppCompat.Light">
  <!-- customize the color palette -->
  <item name="colorPrimary">@color/material_blue_500</item>
  <item name="colorPrimaryDark">@color/material_blue_700</item>
  <item name="colorAccent">@color/material_green_A200</item>
</style>

dependencies {
  compile 'com.android.support:appcompat-v7:21.0.+'
  compile 'com.android.support:cardview-v7:21.0.+'
  compile 'com.android.support:recyclerview-v7:21.0.+'
}

// Check if we're running on Android 5.0 or higher
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
  // Call some material design APIs here
} else {
  // Implement this feature without material design
}

import android.app.Activity; 
import android.os.Bundle; 
import android.support.v7.widget.GridLayoutManager; 
import android.support.v7.widget.RecyclerView; 
import android.support.v7.widget.RecyclerView.LayoutParams; 
import android.view.LayoutInflater; 
import android.view.ViewGroup; 
import android.widget.TextView; 
 
public class RecyclerViewActivity extends Activity { 
  /* 
   * recyclerview提供这些内置的布局管理器： 
   * linearlayoutmanager       显示垂直滚动列表或水平的项目。 
   * gridlayoutmanager        显示在一个网格项目。 
   * staggeredgridlayoutmanager    显示在交错网格项目。 
   * 自定义的布局管理器，需要继承recyclerview.layoutmanager类。 
   * 
   * add/remove items时的动画是默认启用的。 
   * 自定义这些动画需要继承RecyclerView.ItemAnimator，并实现RecyclerView.setItemAnimator() 
   */ 
   private RecyclerView mRecyclerView; 
   private RecyclerView.Adapter mAdapter; 
   private RecyclerView.LayoutManager mLayoutManager; 
   private String[] myDataset; 
 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
     
    setContentView(R.layout.recycler_view); 
    mRecyclerView = (RecyclerView) findViewById(R.id.my_recycler_view); 
 
    // use this setting to improve performance if you know that changes 
    // in content do not change the layout size of the RecyclerView 
    mRecyclerView.setHasFixedSize(true); 
 
    // use a linear layout manager 
//    mLayoutManager = new LinearLayoutManager(this); 
     
//    mLayoutManager = new GridLayoutManager(this, 3, GridLayoutManager.VERTICAL, true); 
    //true 表示，将layout内容反转 
    mLayoutManager = new GridLayoutManager(this, 3, GridLayoutManager.VERTICAL, false); 
    //HORIZONTAL 横向滚动显示内容  VERTICAL纵向 
//    mLayoutManager = new GridLayoutManager(this, 3, GridLayoutManager.HORIZONTAL, false); 
     
    //方向也是指示滚动方向，例子中横向开头的数据交错了一点， 纵向的无交错 
//    mLayoutManager = new StaggeredGridLayoutManager(3, StaggeredGridLayoutManager.HORIZONTAL); 
//    mLayoutManager = new StaggeredGridLayoutManager(4, StaggeredGridLayoutManager.VERTICAL); 
     
    mRecyclerView.setLayoutManager(mLayoutManager); 
//    mRecyclerView.setLayoutManager(new MyLayoutMnager()); //数据不显示，可能还需要重写什么东西。。 
 
    // specify an adapter (see also next example) 
    
    setDatas(); 
    mAdapter = new MyAdapter(myDataset); 
    mRecyclerView.setAdapter(mAdapter); 
  } 
   
  private void setDatas() { 
    int len = 200; 
    myDataset = new String[len]; 
    for (int i = 0; i < len; i++) { 
      switch (i%3) { 
      case 0: 
        myDataset[i] = "中国" + i; 
        break; 
      case 1: 
        myDataset[i] = "美国" + i; 
        break; 
      case 2: 
        myDataset[i] = "澳大利亚" + i; 
        break; 
      } 
    } 
  } 
   
  class MyLayoutMnager extends RecyclerView.LayoutManager { 
 
    @Override 
    public LayoutParams generateDefaultLayoutParams() { 
      LayoutParams params = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); 
      params.topMargin = 5; 
      return params; 
    } 
  } 
   
  class MyAdapter extends RecyclerView.Adapter<ViewHolder> { 
    private String[] mDataset; 
 
    // Provide a reference to the views for each data item 
    // Complex data items may need more than one view per item, and 
    // you provide access to all the views for a data item in a view holder 
 
    // Provide a suitable constructor (depends on the kind of dataset) 
    public MyAdapter(String[] myDataset) { 
      mDataset = myDataset; 
    } 
 
    // Create new views (invoked by the layout manager) 
    @Override 
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { 
      // create a new view 
      TextView tv = (TextView) LayoutInflater.from(parent.getContext()) 
          .inflate(R.layout.my_text_view, parent, false); 
      // set the view's size, margins, paddings and layout parameters 
      //... 
      ViewHolder vh = new ViewHolder(tv); //构建一个ViewHolder 
      return vh; 
    } 
 
    // Replace the contents of a view (invoked by the layout manager) 
    @Override 
    public void onBindViewHolder(ViewHolder holder, int position) { 
      // - get element from your dataset at this position 
      // - replace the contents of the view with that element 
      holder.mTextView.setText(mDataset[position]); 
 
    } 
 
    // Return the size of your dataset (invoked by the layout manager) 
    @Override 
    public int getItemCount() { 
      return mDataset.length; 
    } 
  } 
   
  static class ViewHolder extends RecyclerView.ViewHolder { 
    // each data item is just a string in this case 
    public TextView mTextView; 
    public ViewHolder(TextView v) { 
      super(v); 
      mTextView = v; 
    } 
  } 
}