android自带的下拉刷新

1.layout.xml中代码:
  <android.support.v4.widget.SwipeRefreshLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/swipe_container"
    tools:context="com.dhcc.simple.MainActivity">

    <ListView
        android:id="@+id/listview"
        android:padding="10dp"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        />
  </android.support.v4.widget.SwipeRefreshLayout>
2.java code:
  public class MainActivity extends AppCompatActivity implements SwipeRefreshLayout.OnRefreshListener {

    private SwipeRefreshLayout mSwipeRefreshLayout;
    private ListView mListView;
    private List<String> mData ;
    private ArrayAdapter<String> mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initData();
        mSwipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.swipe_container);
        mListView = (ListView) findViewById(R.id.listview);
        if (mAdapter == null){
            mAdapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,mData);
        }
        mListView.setAdapter(mAdapter);
        mSwipeRefreshLayout.setOnRefreshListener(this);
        mSwipeRefreshLayout.setColorSchemeResources(android.R.color.holo_blue_bright,
                android.R.color.holo_green_light, android.R.color.holo_orange_light,
                android.R.color.holo_red_light);
    }

    private void initData() {
        if (mData == null) {
           mData = new ArrayList<String>();
            for (int i = 0;i < 10;i++){
                mData.add("item" + i);
            }
        }
    }

    @Override
    public void onRefresh() {
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                mSwipeRefreshLayout.setRefreshing(false);
            }
        },2000);
    }
}