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Android-PullToRefresh下拉刷新库基本用法

PullToRefresh是一套实现非常好的下拉刷新库,它支持:
ListView
ExpandableListView
GridView
WebView
ScrollView
HorizontalScrollView
ViewPager
等多种常用的需要刷新的View类型,而且使用起来也十分方便。
(下载地址:https://github.com/chrisbanes/Android-PullToRefresh)

PullToRefresh基本用法:
1、在布局文件中添加PullToRefresh控件,比如PullToRefreshListView;
2、在Activity中,设置监听器OnRefreshListener以响应用户下拉操作;
3、在监听器的onRefresh()方法中执行数据刷新操作,可以通过AsyncTask来实现;
4、在AsyncTask中获取到数据后,记得调用onRefreshComplete()方法通知PullToRefresh控件数据已获取完毕,可以结束刷新操作。

实例:PullToRefreshDemo
运行效果:

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视图结构

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代码清单:
布局文件:activity_main.xml
<RelativeLayout 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: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=".MainActivity" >
 
    <com.handmark.pulltorefresh.library.PullToRefreshListView
        android:id="@+id/pull_to_refresh_listview"
        android:layout_height="fill_parent"
        android:layout_width="fill_parent" />

</RelativeLayout>

Java源代码文件:MainActivity.java

package com.rainsong.pulltorefreshdemo;

import java.util.Arrays;
import java.util.LinkedList;

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.text.format.DateUtils;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import com.handmark.pulltorefresh.library.PullToRefreshBase;
import com.handmark.pulltorefresh.library.PullToRefreshBase.OnRefreshListener;
import com.handmark.pulltorefresh.library.PullToRefreshListView;

public class MainActivity extends Activity {
    private PullToRefreshListView mPullToRefreshListView;
    private LinkedList<String> mListItems;
    private ArrayAdapter<String> mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        // Set a listener to be invoked when the list should be refreshed.
        mPullToRefreshListView = (PullToRefreshListView) findViewById(R.id.pull_to_refresh_listview);
        mPullToRefreshListView.setOnRefreshListener(new OnRefreshListener<ListView>() {
            @Override
            public void onRefresh(PullToRefreshBase<ListView> refreshView) {
                String label = DateUtils.formatDateTime(getApplicationContext(), System.currentTimeMillis(),
                        DateUtils.FORMAT_SHOW_TIME | DateUtils.FORMAT_SHOW_DATE | DateUtils.FORMAT_ABBREV_ALL);
                
                // Update the LastUpdatedLabel
                refreshView.getLoadingLayoutProxy().setLastUpdatedLabel(label);
                
                // Do work to refresh the list here.
                new GetDataTask().execute();
            }
        });
        
        ListView actualListView = mPullToRefreshListView.getRefreshableView();
        
        mListItems = new LinkedList<String>();
        mListItems.addAll(Arrays.asList(mStrings));
        
        mAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, mListItems);
        actualListView.setAdapter(mAdapter);
    }
    
    private class GetDataTask extends AsyncTask<Void, Void, String[]> {

        @Override
        protected String[] doInBackground(Void... params) {
            // Simulates a background job.
            try {
                Thread.sleep(4000);
            } catch (InterruptedException e) {
            }
            return mStrings;
        }
        @Override
        protected void onPostExecute(String[] result) {
            mListItems.addFirst("Added after refresh...");
            mAdapter.notifyDataSetChanged();
            
            // Call onRefreshComplete when the list has been refreshed.
            mPullToRefreshListView.onRefreshComplete();
            super.onPostExecute(result);
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    private String[] mStrings = { "John", "Michelle", "Amy", "Kim", "Mary",
            "David", "Sunny", "James", "Maria", "Michael", "Sarah", "Robert",
            "Lily", "William", "Jessica", "Paul", "Crystal", "Peter",
            "Jennifer", "George", "Rachel", "Thomas", "Lisa", "Daniel", "Elizabeth",
            "Kevin" };
}

实例源代码下载 http://download.csdn.net/detail/hantangsongming/8336075



Android-PullToRefresh下拉刷新库基本用法