android官方下拉刷新控件SwipeRefreshLayout的使用

可能开发安卓的人大多数都用过很多下拉刷新的开源组件，但是今天用了官方v4支持包的SwipeRefreshLayout觉得效果也蛮不错的，特拿出来分享。

简介：
SwipeRefreshLayout组件只接受一个子组件：即需要刷新的那个组件。它使用一个侦听机制来通知拥有该组件的监听器有刷新事件发生，换句话说我们的Activity必须实现通知的接口。该Activity负责处理事件刷新和刷新相应的视图。一旦监听者接收到该事件，就决定了刷新过程中应处理的地方。如果要展示一个“刷新动画”，它必须调用setRefrshing（true），否则取消动画就调用setRefreshing（false）。

并且这个东西只支持下拉刷新，大家可以自定义View继承它实现你的上拉加载。

怎样使用SwipeRefreshLayout：
使用起来非常简单。
下面将用一个实例展示如何使用官方这个下拉刷新控件，末尾我还模仿虚拟实现了一个小的上拉加载效果，可以供大家向上分析。

先上图：

上点代码：

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<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"
    tools:context="com.example.nanchen.swiperefreshlayoutdemo.MainActivity">
 
 
    <android.support.v4.widget.SwipeRefreshLayout
        android:id="@+id/main_srl"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
 
 
        <ListView
            android:id="@+id/main_lv"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content">
        </ListView>
    </android.support.v4.widget.SwipeRefreshLayout>
</RelativeLayout>

menu_layout.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">
 
 
    <ProgressBar
        style="?android:attr/progressBarStyleSmall"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/progressBar"/>
 
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="正在玩命加载中...."
        android:id="@+id/textView2"/>
 
 
</LinearLayout>

　　MainActivity.java

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package com.example.nanchen.swiperefreshlayoutdemo;
 
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.AbsListView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
 
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
 
public class MainActivity extends AppCompatActivity implements AbsListView.OnScrollListener {
 
    private SwipeRefreshLayout swipeRefreshLayout;
    private ListView lv;
    private ArrayAdapter adapter;
    private List<String> list;
    private View footerView;
 
    private Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            switch (msg.what){
                case 0x101:
                    if (swipeRefreshLayout.isRefreshing()){
                        adapter.notifyDataSetChanged();
                        swipeRefreshLayout.setRefreshing(false);//设置不刷新
                    }
                    break;
            }
        }
    };
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
        swipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.main_srl);
        lv = (ListView) findViewById(R.id.main_lv);
 
        footerView = getLayoutInflater().inflate(R.layout.loading_layout,null);
        lv.addFooterView(footerView);
 
        lv.setOnScrollListener(this);
 
        list = new ArrayList<>();
        list.addAll(Arrays.asList("Java","php","C++","C#","IOS","html","C","J2ee","j2se","VB",".net","Http","tcp","udp","www"));
 
        adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1,
                android.R.id.text1,list);
        lv.setAdapter(adapter);
 
        swipeRefreshLayout.setColorSchemeResources(android.R.color.holo_blue_bright, android.R.color.holo_green_light,
                android.R.color.holo_orange_light, android.R.color.holo_red_light);
 
        swipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
            @Override
            public void onRefresh() {
                new LoadDataThread().start();
            }
        });
    }
 
    private int visibleLastIndex;//用来可显示的最后一条数据的索引
    @Override
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        if(adapter.getCount() == visibleLastIndex && scrollState == SCROLL_STATE_IDLE){
            new LoadDataThread().start();
        }
    }
 
    @Override
    public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
        visibleLastIndex = firstVisibleItem + visibleItemCount - 1;//减去最后一个加载中那条
    }
 
 
 
    /**
     * 模拟加载数据的线程
     */
    class LoadDataThread extends  Thread{
        @Override
        public void run() {
            initData();
            try {
                Thread.sleep(2000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            handler.sendEmptyMessage(0x101);//通过handler发送一个更新数据的标记
        }
 
        private void initData() {
            list.addAll(Arrays.asList("Json","XML","UDP","http"));
        }
    }
 
 
 
 
 
}