ListView下拉刷新（慕課網教材源碼）

MainActivity

package com.imooc.listviewfrashdemo1;

import java.util.ArrayList;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;

import com.example.listviewfrashdemo1.R;
import com.imooc.listviewfrashdemo1.ReFlashListView.IReflashListener;

public class MainActivity extends Activity implements IReflashListener{
    ArrayList<ApkEntity> apk_list;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        setData();
        showList(apk_list);
    }

    MyAdapter adapter;
    ReFlashListView listview;
    private void showList(ArrayList<ApkEntity> apk_list) {
        if (adapter == null) {
            listview = (ReFlashListView) findViewById(R.id.listview);
            listview.setInterface(this);
            adapter = new MyAdapter(this, apk_list);
            listview.setAdapter(adapter);
        } else {
            adapter.onDateChange(apk_list);
        }
    }

    private void setData() {
        apk_list = new ArrayList<ApkEntity>();
        for (int i = 0; i < 10; i++) {
            ApkEntity entity = new ApkEntity();
            entity.setName("Ĭ������");
            entity.setDes("����һ�������Ӧ��");
            entity.setInfo("50w�û�");
            apk_list.add(entity);
        }
    }

    private void setReflashData() {
        for (int i = 0; i < 2; i++) {
            ApkEntity entity = new ApkEntity();
            entity.setName("ˢ������");
            entity.setDes("����һ�������Ӧ��");
            entity.setInfo("50w�û�");
            apk_list.add(0,entity);
        }
    }
    @Override
    public void onReflash() {
        // TODO Auto-generated method stub\
        Handler handler = new Handler();
        handler.postDelayed(new Runnable() {

            @Override
            public void run() {
                // TODO Auto-generated method stub
                //��ȡ��������
                setReflashData();
                //֪ͨ������ʾ
                showList(apk_list);
                //֪ͨlistview ˢ��������ϣ�
                listview.reflashComplete();
            }
        }, 2000);

    }
}

ApkEntity.class

package com.imooc.listviewfrashdemo1;

public class ApkEntity {
    private String name;
    private String des;
    private String info;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getDes() {
        return des;
    }
    public void setDes(String des) {
        this.des = des;
    }
    public String getInfo() {
        return info;
    }
    public void setInfo(String info) {
        this.info = info;
    }

}

MyAdapter.class

package com.imooc.listviewfrashdemo1;

import java.util.ArrayList;

import com.example.listviewfrashdemo1.R;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

public class MyAdapter extends BaseAdapter {
    ArrayList<ApkEntity> apk_list;
    LayoutInflater inflater;

    public MyAdapter(Context context, ArrayList<ApkEntity> apk_list) {
        this.apk_list = apk_list;
        this.inflater = LayoutInflater.from(context);
    }

    public void onDateChange(ArrayList<ApkEntity> apk_list) {
        this.apk_list = apk_list;
        this.notifyDataSetChanged();
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return apk_list.size();
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return apk_list.get(position);
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        ApkEntity entity = apk_list.get(position);
        ViewHolder holder;
        if (convertView == null) {
            holder = new ViewHolder();
            convertView = inflater.inflate(R.layout.item_layout, null);
            holder.name_tv = (TextView) convertView
                    .findViewById(R.id.item3_apkname);
            holder.des_tv = (TextView) convertView
                    .findViewById(R.id.item3_apkdes);
            holder.info_tv = (TextView) convertView
                    .findViewById(R.id.item3_apkinfo);
            convertView.setTag(holder);
        }else{
            holder = (ViewHolder) convertView.getTag();
        }
        holder.name_tv.setText(entity.getName());
        holder.des_tv.setText(entity.getDes());
        holder.info_tv.setText(entity.getInfo());
        return convertView;
    }

    class ViewHolder {
        TextView name_tv;
        TextView des_tv;
        TextView info_tv;
    }
}

ReFlashListView.class

package com.imooc.listviewfrashdemo1;

import com.example.listviewfrashdemo1.R;

import android.content.Context;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.MeasureSpec;
import android.view.ViewGroup;
import android.view.animation.RotateAnimation;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;

public class ReFlashListView extends ListView implements OnScrollListener {  

    private View header;  
    private int headerHeight;// 頂部佈局文件的高度  
    private int firstVisibleItem;// 當前第一個可見的item的位置  
    private int scrollStste;// listview 當前滾動狀態  

    private boolean isRemark;// 標記，當前是在ListView的最頂端按下  
    private int startY;// 按下時的Y值  

    private int state;// 當前狀態  
    private final int NONE = 0;// 正常狀態  
    private final int PULL = 1;// 提示下拉狀態  
    private final int RELSE = 2;// 提示釋放狀態  
    private final int REFLASHING = 3;// 刷新狀態  

    private IReflashListener reflashListener;// 刷新數據的接口  

    public ReFlashListView(Context context) {  
        super(context);  
        initView(context);  
    }  

    public ReFlashListView(Context context, AttributeSet attrs) {  
        super(context, attrs);  
        initView(context);  
    }  

    public ReFlashListView(Context context, AttributeSet attrs, int defStyle) {  
        super(context, attrs, defStyle);  
        initView(context);  
    }  

    /** 
     * 初始化界面，添加頂部佈局文件到listview裏面 
     *  
     * @param context 
     */  
    private void initView(Context context) {  
        LayoutInflater inflater = LayoutInflater.from(context);  
        header = inflater.inflate(R.layout.header_layout, null);  
        measureView(header);  
        headerHeight = header.getMeasuredHeight();  
        topPadding(-headerHeight);  
        this.addHeaderView(header);  
        this.setOnScrollListener(this);  
    }  

    /** 
     * 通知父佈局，佔用多大地方 
     *  
     * @param v 
     */  
    private void measureView(View v) {  
        ViewGroup.LayoutParams p = v.getLayoutParams();  
        if (p == null) {  
            p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,  
                    ViewGroup.LayoutParams.WRAP_CONTENT);  
        }  
        int width = ViewGroup.getChildMeasureSpec(0, 0, p.width);  
        int height;  
        int tempHeight = p.height;  
        if (tempHeight > 0) {  
            height = MeasureSpec.makeMeasureSpec(tempHeight,  
                    MeasureSpec.EXACTLY);  
        } else {  
            height = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED);  
        }  
        v.measure(width, height);  
    }  

    /** 
     * 設置header佈局的上邊距 
     *  
     * @param topPadding 
     */  
    private void topPadding(int topPadding) {  
        header.setPadding(header.getPaddingLeft(), topPadding,  
                header.getPaddingRight(), header.getPaddingBottom());  
        header.invalidate();  
    }  

    @Override  
    public void onScroll(AbsListView arg0, int firstVisibleItem, int arg2,  
            int arg3) {  
        this.firstVisibleItem = firstVisibleItem;  
    }  

    @Override  
    public void onScrollStateChanged(AbsListView arg0, int scrollStste) {  
        this.scrollStste = scrollStste;  
    }  

    @Override  
    public boolean onTouchEvent(MotionEvent ev) {  
        switch (ev.getAction()) {  
        case MotionEvent.ACTION_DOWN:  
            if (firstVisibleItem == 0) {  
                isRemark = true;  
                startY = (int) ev.getY();  
            }  
            break;  
        case MotionEvent.ACTION_MOVE:  
            onMove(ev);  
            break;  

        case MotionEvent.ACTION_UP:  
            if (state == RELSE) {  
                state = REFLASHING;  
                reflashViewByState();  
                // 加載最新數據  
                reflashListener.onReflash();  
            } else if (state == PULL) {  
                state = NONE;  
                isRemark = false;  
                reflashViewByState();  
            }  
            break;  
        }  
        return super.onTouchEvent(ev);  
    }  

    /** 
     * 判斷移動過程中的操作 
     *  
     * @param ev 
     */  
    private void onMove(MotionEvent ev) {  
        if (!isRemark) {  
            return;  
        }  
        int tempY = (int) ev.getY();  
        int space = tempY - startY;  
        int topPadding = space - headerHeight;  
        switch (state) {  
        case NONE:  
            // 下拉狀態  
            if (space > 0) {  
                state = PULL;  
                reflashViewByState();  
            }  
            break;  

        case PULL:  
            topPadding(topPadding);  
            // 下拉達到一定程度，並且ListView當前是滾動狀態  
            if (space > headerHeight + 30  
                    && scrollStste == SCROLL_STATE_TOUCH_SCROLL) {  
                state = RELSE;  
                reflashViewByState();  
            }  
            break;  
        case RELSE:  
            topPadding(topPadding);  
            if (space < headerHeight + 30) {  
                state = PULL;  
                reflashViewByState();  
            } else if (space <= 0) {  
                state = NONE;  
                isRemark = false;  
                reflashViewByState();  
            }  
            break;  
        }  
    }  

    /** 
     * 根據當前狀態改變界面顯示 
     */  
    private void reflashViewByState() {  
        TextView tip = (TextView) header.findViewById(R.id.tip);  
        ImageView arrow = (ImageView) header.findViewById(R.id.arrow);  
        ProgressBar progress = (ProgressBar) header.findViewById(R.id.progress);  

        RotateAnimation anim = new RotateAnimation(0, 180,  
                RotateAnimation.RELATIVE_TO_SELF, 0.5f,  
                RotateAnimation.RELATIVE_TO_SELF, 0.5f);  
        anim.setDuration(500);  
        anim.setFillAfter(true);  
        RotateAnimation anim1 = new RotateAnimation(180, 0,  
                RotateAnimation.RELATIVE_TO_SELF, 0.5f,  
                RotateAnimation.RELATIVE_TO_SELF, 0.5f);  
        anim1.setDuration(500);  
        anim1.setFillAfter(true);  

        switch (state) {  
        case NONE:  
            topPadding(-headerHeight);  
            arrow.clearAnimation();  
            break;  

        case PULL:  
            arrow.setVisibility(View.VISIBLE);  
            progress.setVisibility(View.GONE);  
            tip.setText("下拉可以刷新");  
            arrow.clearAnimation();  
            arrow.setAnimation(anim1);  
            break;  
        case RELSE:  
            arrow.setVisibility(View.VISIBLE);  
            progress.setVisibility(View.GONE);  
            tip.setText("鬆開可以刷新");  
            arrow.clearAnimation();  
            arrow.setAnimation(anim);  
            break;  
        case REFLASHING:  
            arrow.clearAnimation();  
            topPadding(0);// 刷新的時候高度固定不變  
            arrow.setVisibility(View.GONE);  
            progress.setVisibility(View.VISIBLE);  
            tip.setText("正在刷新");  
            break;  
        }  
    }  

    /** 
     * 獲取完數據 
     */  
    public void reflashComplete() {  
        state = NONE;  
        isRemark = false;  
        reflashViewByState();  
    }  

    public void setInterface(IReflashListener reflashListener) {  
        this.reflashListener = reflashListener;  
    }  

    /** 
     * 刷新數據接口 
     */  
    public interface IReflashListener {  
        public void onReflash();  
    }  
}  

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:background="@color/white"
    tools:context=".MainActivity" >

    <com.imooc.listviewfrashdemo1.ReFlashListView
        android:id="@+id/listview"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:background="@color/white"
        android:cacheColorHint="#00000000"
        android:dividerHeight="5dip" />
</RelativeLayout>

header_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="wrap_content"
    android:orientation="vertical" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:paddingBottom="10dip"
        android:paddingTop="10dip" >

        <LinearLayout
            android:id="@+id/layout"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:gravity="center"
            android:orientation="vertical" >

            <TextView
                android:id="@+id/tip"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="下拉可以刷新！" />

            <TextView
                android:id="@+id/lastupdate_time"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
        </LinearLayout>

        <ImageView
            android:id="@+id/arrow"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toLeftOf="@id/layout"
            android:layout_marginRight="20dip"
            android:src="@drawable/pull_to_refresh_arrow" />

        <ProgressBar
            android:id="@+id/progress"
            style="?android:attr/progressBarStyleSmall"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toLeftOf="@id/layout"
            android:layout_marginRight="20dip"
            android:visibility="gone" />
    </RelativeLayout>

</LinearLayout>

item_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"
    android:orientation="vertical" >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="60dip"
        android:gravity="center_vertical"
        android:background="@drawable/app_item_bg"
        android:orientation="horizontal" >

        <ImageView
            android:id="@+id/item3_apkiv"
            android:layout_width="50dip"
            android:layout_height="50dip"
            android:background="@drawable/test_icon"
            android:layout_marginLeft="10dip" />

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:layout_marginLeft="10dip"
            android:orientation="vertical" >

            <TextView
                android:id="@+id/item3_apkname"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="應用程序名字"
                android:textColor="@color/black"
                android:textSize="18dip" />

            <TextView
                android:id="@+id/item3_apkinfo"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="5dip"
                android:text="應用程序信息"
                android:textSize="14dip" />
        </LinearLayout>
        <Button
            android:layout_width="60dip"
            android:layout_height="30dip"
            android:background="@drawable/dlbtn_selector"
            android:id="@+id/item3_dlbtn"
            android:layout_marginRight="10dip"
            android:text="安裝"
            />
    </LinearLayout>

    <TextView
        android:id="@+id/item3_apkdes"
        android:layout_width="fill_parent"
        android:layout_height="30dip"
        android:layout_marginLeft="5dip"
        android:layout_marginRight="5dip"
        android:gravity="center_vertical"
        android:text="應用程序描述"
        android:textSize="14dip" />

</LinearLayout>