PullToRefresh的简单使用

杭州寿星 4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