android系统自带的下拉刷新控件SwipeRefreshLayout位于android.support.v4.widget包下，实现步骤如下：

1.在布局文件中添加该控件，该控件一般作为父控件，而且只能包含有一个子控件，并且这个子控件是能够滑动的，比如scrollview，listview等

2.实现OnRefreshListener接口，并重写onRefresh函数

详细代码如下：

xmlns:tools="http://schemas.android.com/tools"

android:id="@+id/swipe_refresh"

android:layout_width="match_parent"

android:layout_height="match_parent" >

android:id="@+id/scrollview"

android:layout_width="match_parent"

android:layout_height="match_parent" >

android:layout_width="match_parent"

android:layout_height="wrap_content"

android:orientation="vertical"

>

android:id="@+id/tip_text"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="@string/pull_fresh"

android:textSize="15sp"

/>

android:id="@+id/random_text"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:textColor="#FF000000"

android:textSize="15sp"

/>

import android.app.Activity;

import android.os.Bundle;

import android.os.Handler;

import android.support.v4.widget.SwipeRefreshLayout;

import android.support.v4.widget.SwipeRefreshLayout.OnRefreshListener;

import android.widget.TextView;

/**

MainActivity---系统下拉刷新控件的实现

@author seabear

*/

public class MainActivity extends Activity implements OnRefreshListener{

private SwipeRefreshLayout mSwipeRefreshLayout;

private TextView mRandomText;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

mSwipeRefreshLayout = (SwipeRefreshLayout)this.findViewById(R.id.swipe_refresh);

mSwipeRefreshLayout.setOnRefreshListener(this);

mRandomText = (TextView)this.findViewById(R.id.random_text);

}

@Override

public void onRefresh() {

mSwipeRefreshLayout.setRefreshing(true);

(new Handler()).postDelayed(new Runnable() {

@Override

public void run() {

//3秒后停止刷新

mSwipeRefreshLayout.setRefreshing(false);

int num = (int)(Math.random() * 100 + 1);

String s = mRandomText.getText().toString();

s = s + " " + num;

mRandomText.setText(s);

}

}, 3000);

}

}