8.高级控件（二）之 PullToRefresh下拉刷新(第三方)

一:下载

1.联网搜索www.github.com(最优秀的开源网站)

2.在网站里搜索pull to refresh

接下来如下图所示：

二:在Android Studio中导入你下载的第三方

至此，在项目中导入第三方已经完成。

需要注意的是，第三方里面有的东西可能过时，像第三方的java文件PullToRefreshWebView.java可能报错,就需要改，如下图所示

然后

三:编写测试代码

接下来就比较简单了，直接根据官方文档编写代码。

layout布局文件

activity_pulltorefresh.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.handmark.pulltorefresh.library.PullToRefreshListView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:id="@+id/ptrlv_refresh"
            >
    </com.handmark.pulltorefresh.library.PullToRefreshListView>

</LinearLayout>

Activity的java代码
PullToRefreshActivity.java

package com.zking.android08_widgetplus;

import android.os.AsyncTask;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;

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

import java.util.ArrayList;
import java.util.List;

/**
 * @author Zking-Snail
 * @time 2017/6/9 16:35
 * @Version ${REV}
 */
public class PullToRefreshActivity extends AppCompatActivity {

        private PullToRefreshListView ptrlv_refresh;

        private List<String> list=new ArrayList<>();
        private ArrayAdapter adapter;

        @Override
        protected void onCreate(@Nullable Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.activity_pulltorefresh);
                ptrlv_refresh = (PullToRefreshListView) findViewById(R.id.ptrlv_refresh);

                for (int i = 0; i <10 ; i++) {
                    list.add("admin爱小小和喵喵"+i+"次");
                }
                adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,list);
                ptrlv_refresh.setAdapter(adapter);


                //给ListView设置下拉刷新的监听
                ptrlv_refresh.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2<ListView>() {
                    @Override
                    public void onPullDownToRefresh(PullToRefreshBase<ListView> refreshView) {

                        new MyTask().execute();

                    }

                    @Override
                    public void onPullUpToRefresh(PullToRefreshBase<ListView> refreshView) {

                    }
                });
            }

            class MyTask extends AsyncTask{

                //在后台 获取数据
                //内部有线程机制
                @Override
                protected Object doInBackground(Object[] objects) {
                    for (int i = 0; i <3 ; i++) {
                        list.add(0,"小小和喵喵也爱admin"+i+"次");
                    }
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    return null;
                }

                //更新UI
                @Override
                protected void onPostExecute(Object o) {
                    super.onPostExecute(o);

                    ptrlv_refresh.onRefreshComplete();
                    //通知适配器数据 发生改变
                    adapter.notifyDataSetChanged();

                }
        }
}

配置AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.zking.android08_widgetplus">

    <application android:allowBackup="true" android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true" android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">

        </activity>
        <activity android:name=".PullToRefreshActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

四:效果图
   

最后，一通百通，像XListView这样的下拉刷新控件也差不多可以这样写。

欢迎大家来指出我的不足哦O(∩_∩)O~