PullToRefresh的简单使用
杭州寿星
8年前
来自： http://blog.csdn.net//chenguang79/article/details/43194637
在做android项目的时候，我们经常要用到上拉刷新列表，下拉刷新列表的功能，这里简单介绍一个PullToRefresh的使用。
一，下载PullToRefresh，地址：https://github.com/chrisbanes/Android-PullToRefresh。这里面，我们只要其中的Library工程。将它引入我们的工程，在android studio1.01中的引用方法，请看http://blog.csdn.net/chenguang79/article/details/43150303
二，应用，这里我使用了一个自定义的Adapter，我感觉这样能更好的和实战结和起来。下面是代码，我在代码里，都进行了注解
１，布局文件（activity_user_defined_list__pulltore_fresh.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:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:paddingBottom="@dimen/activity_vertical_margin" tools:context="com.example.cg.studiotest.userDefinedList_PulltoreFresh"> <!--下面就是PullToRefresh控件--> <com.handmark.pulltorefresh.library.PullToRefreshListView android:id="@+id/userDefinedList_pull_refresh_list" android:layout_width="fill_parent" android:layout_height="fill_parent" android:cacheColorHint="#00000000" android:divider="#19000000" android:dividerHeight="4dp" android:fadingEdge="none" android:fastScrollEnabled="false" android:footerDividersEnabled="false" android:headerDividersEnabled="false" android:smoothScrollbar="true" /> </RelativeLayout>
这个控件的属性基本上和listVIew是一样的，就不多说了。
２，列表布局文件（pulltorefresh_item.xml）
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="horizontal"> <TextView android:id="@+id/txt_pulltorefresh_item_title" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <ImageView android:id="@+id/img_pulltorefresh_item_img" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/ic_launcher"/> </LinearLayout>
３，程序（userDefinedList_PulltoreFresh.java）
package com.example.cg.studiotest; import android.app.Activity; import android.os.AsyncTask; import android.os.Bundle; import android.text.format.DateUtils; import android.widget.ListView; import android.widget.Toast; import com.example.cg.baseAdapter.pulltorefresh_baseAdapter; import com.handmark.pulltorefresh.library.PullToRefreshBase; import com.handmark.pulltorefresh.library.PullToRefreshListView; import java.util.ArrayList; import java.util.List; public class userDefinedList_PulltoreFresh extends Activity { //定义下拉刷新列表控件 private PullToRefreshListView userDefinedList_pull_refresh_list; //定义原始数据源 private String[] mainStr = {"宋元通宝","太平通宝","淳化元宝","至道元宝","咸平元宝","景德元宝","祥福元宝", "祥福通宝","天禧通宝","天圣元宝","明道元宝","景祐元宝","皇宝通宝","庆历重宝"}; //定义新加的数据源 private String[] strArray = {"至和元宝","至和重宝","嘉祐元宝","喜祐通宝","治平元宝","熙宁元宝","熙宁通宝"}; //定义要从新的数据源中取出哪个值 private int num; //定义List的Adapter private pulltorefresh_baseAdapter pullAdapter; //定义向Adaptger中传值的数据 private List<String> listDate; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_user_defined_list__pulltore_fresh); //初始化数据 listDate = new ArrayList<String>(); //初始化值 num = 0; //循环给数据赋值 for(int i=0;i<mainStr.length;i++) { listDate.add(mainStr[i]); } //初始化下拉列表控件 userDefinedList_pull_refresh_list = (PullToRefreshListView)this.findViewById(R.id.userDefinedList_pull_refresh_list); userDefinedList_pull_refresh_list.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener<ListView>() { @Override public void onRefresh(PullToRefreshBase<ListView> refreshView) { String twoInfo = DateUtils.formatDateTime(getApplicationContext(),System.currentTimeMillis(), DateUtils.FORMAT_SHOW_TIME | DateUtils.FORMAT_SHOW_DATE | DateUtils.FORMAT_ABBREV_ALL); //下拉时，显示的主要文字，一般的情况下，我们不修改它 refreshView.getLoadingLayoutProxy().setReleaseLabel("放手开始加载数据"); //下拉时，第二行显示的文字 refreshView.getLoadingLayoutProxy().setLastUpdatedLabel(twoInfo); //数据刷新的时候，显示的文字 refreshView.getLoadingLayoutProxy().setRefreshingLabel("数据加载中......"); //刷新结束后，显示的文字，没有什么意义，一间而过 refreshView.getLoadingLayoutProxy().setPullLabel("数据加载完成!"); //调用异步，开始加载 new GetDataTask().execute(); } }); //设置底部下拉刷新模式 userDefinedList_pull_refresh_list.setMode(PullToRefreshBase.Mode.PULL_FROM_END); pullAdapter = new pulltorefresh_baseAdapter(this,listDate); //设置适配器 ListView actualListView = userDefinedList_pull_refresh_list.getRefreshableView(); actualListView.setAdapter(pullAdapter); } private class GetDataTask extends AsyncTask<Void,Void,String>{ /** * 此处进行异步操作 */ @Override protected String doInBackground(Void... params) { //让程序休眠一秒钟，以达到延时的效果 try { Thread.sleep(1000); } catch (InterruptedException e) { Toast.makeText(userDefinedList_PulltoreFresh.this,e.getMessage(),Toast.LENGTH_LONG).show(); } //定义一个变量，用来存取要添加的值，当num值大于新加数据的个数时，就不再给值，而是返回空 String str = ""; if(num!=strArray.length) { str = strArray[num]; num++; } return str; } /** * 这里是异步操作完，返回的结果，用来修改UI * @param backStr 异步返回的结果 */ @Override protected void onPostExecute(String backStr) { //判断一下，传过来的值是否为空，如是不为空则进行添加 if(!backStr.equals("")) { listDate.add(backStr); } pullAdapter.notifyDataSetChanged(); userDefinedList_pull_refresh_list.onRefreshComplete(); super.onPostExecute(backStr); } } } ４，Adapter文件（pulltorefresh_baseAdapter.java）
package com.example.cg.baseAdapter; import android.content.Context; import android.util.Log; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.TextView; import com.example.cg.studiotest.R; import java.util.List; /** * Created by cg on 2015/1/27. */ public class pulltorefresh_baseAdapter extends BaseAdapter { private LayoutInflater mInflater; private List<String> testDate; public pulltorefresh_baseAdapter(Context context,List<String> testDate) { this.mInflater = LayoutInflater.from(context); this.testDate = testDate; } @Override public int getCount() { return testDate.size(); } @Override public Object getItem(int position) { return testDate.get(position); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { pulltoreItem item; if(convertView==null) { item = new pulltoreItem(); convertView = mInflater.inflate(R.layout.pulltorefresh_item, null); item.txt_pulltorefresh_item_title = (TextView)convertView.findViewById(R.id.txt_pulltorefresh_item_title); item.img_pulltorefresh_item_img = (ImageView)convertView.findViewById(R.id.img_pulltorefresh_item_img); convertView.setTag(item); } else { item = (pulltoreItem)convertView.getTag(); } item.txt_pulltorefresh_item_title.setText(testDate.get(position)); return convertView; } public class pulltoreItem { TextView txt_pulltorefresh_item_title; ImageView img_pulltorefresh_item_img; } } ５，效果图
