Android pulltorefresh使用，androidpulltorefresh

Android pulltorefresh使用，androidpulltorefresh

pulltorefresh外掛程式可以輕鬆實現上拉下拉重新整理，github.com上直接搜尋進行下載。

布局檔案:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:ptr="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >    <com.handmark.pulltorefresh.library.PullToRefreshListView    android:id="@+id/pull_to_refresh_listview"    android:layout_height="fill_parent"    android:layout_width="fill_parent"    ptr:ptrDrawable="@drawable/default_ptr_flip"    ptr:ptrAnimationStyle="flip"    ptr:ptrHeaderBackground="@android:color/transparent"    ptr:ptrHeaderTextColor="#919191"     /></RelativeLayout>

核心代碼如下，這裡用到了Android當中不少的知識點，其中主要的是非同步任務處理、自訂配接器。

package com.example.pulltorefresh;import java.util.ArrayList;import com.handmark.pulltorefresh.library.ILoadingLayout;import com.handmark.pulltorefresh.library.PullToRefreshBase;import com.handmark.pulltorefresh.library.PullToRefreshListView;import android.os.AsyncTask;import android.os.Bundle;import android.app.Activity;import android.content.Context;import android.view.LayoutInflater;import android.view.Menu;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.TextView;public class MainActivity extends Activity {    private PullToRefreshListView pullToRefreshView;    private ArrayList<Music> musics=new ArrayList<Music>();    private DataAdapter dataAdapter;    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);                pullToRefreshView = (PullToRefreshListView) findViewById(R.id.pull_to_refresh_listview);        pullToRefreshView.setOnRefreshListener(new PullToRefreshBase.OnRefreshListener2() {            @Override            public void onPullDownToRefresh(PullToRefreshBase refreshView) {                // TODO 自動產生的方法存根                new DataAsyncTask(MainActivity.this).execute();            }            @Override            public void onPullUpToRefresh(PullToRefreshBase refreshView) {                // TODO 自動產生的方法存根                new DataAsyncTask(MainActivity.this).execute();            }        });        pullToRefreshView.setMode(PullToRefreshBase.Mode.BOTH);        ILoadingLayout startLabels = pullToRefreshView                    .getLoadingLayoutProxy(true, false);            startLabels.setPullLabel("下拉重新整理...");// 剛下拉時，顯示的提示            startLabels.setRefreshingLabel("正在載入...");// 重新整理時            startLabels.setReleaseLabel("放開重新整理...");// 下來達到一定距離時，顯示的提示                ILoadingLayout endLabels = pullToRefreshView.getLoadingLayoutProxy(                    false, true);            endLabels.setPullLabel("上拉重新整理...");// 剛下拉時，顯示的提示            endLabels.setRefreshingLabel("正在載入...");// 重新整理時            endLabels.setReleaseLabel("放開重新整理...");// 下來達到一定距離時，顯示的提示            loadData();        dataAdapter=new DataAdapter(this, musics);        pullToRefreshView.setAdapter(dataAdapter);    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        // Inflate the menu; this adds items to the action bar if it is present.        getMenuInflater().inflate(R.menu.main, menu);        return true;    }        private int count;    private void loadData(){        for(int i=0;i<10;i++){            musics.add(new Music("歌曲-"+count,"歌手-"+count));            count++;        }    }    static class DataAsyncTask extends AsyncTask<Void, Void, String>{        private MainActivity mainActivity;        public DataAsyncTask(MainActivity mainActivity){            this.mainActivity=mainActivity;        }        @Override        protected String doInBackground(Void... arg0) {            try {                Thread.sleep(2000);            } catch (InterruptedException e) {                // TODO 自動產生的 catch 塊                e.printStackTrace();            }            mainActivity.loadData();            return "success";        }                @Override        protected void onPostExecute(String result) {            // TODO 自動產生的方法存根            super.onPostExecute(result);            if("success".equals(result)){                mainActivity.dataAdapter.notifyDataSetChanged();                mainActivity.pullToRefreshView.onRefreshComplete();                            }        }    }        static class DataAdapter extends BaseAdapter{        private Context ctx;        private ArrayList<Music> musics;        public DataAdapter(Context ctx,ArrayList<Music> musics){            this.ctx=ctx;            this.musics=musics;        }        @Override        public int getCount() {            // TODO 自動產生的方法存根            return musics.size();        }        @Override        public Object getItem(int arg0) {            // TODO 自動產生的方法存根            return musics.get(arg0);        }        @Override        public long getItemId(int arg0) {            // TODO 自動產生的方法存根            return arg0;        }        //ViewHolder就是一個持有人的類，他裡面一般沒有方法，只有屬性，作用就是一個臨時的儲存器，        //把你getView方法中每次返回的View存起來，可以下次再用。這樣做的好處就是不必每次都到布局檔案中去拿到你的View，提高了效率        @Override        public View getView(int arg0, View arg1, ViewGroup arg2) {            ViewHolder vh;            if(arg1==null){                arg1=LayoutInflater.from(ctx).inflate(R.layout.listitem,null);                vh=new ViewHolder();                vh.tv_title=(TextView) arg1.findViewById(R.id.gequ);                vh.tv_singer=(TextView) arg1.findViewById(R.id.geshou);                arg1.setTag(vh);            }            vh=(ViewHolder) arg1.getTag();            Music m=musics.get(arg0);            vh.tv_title.setText(m.getTitle());            vh.tv_singer.setText(m.getSinger());            return arg1;        }                static class ViewHolder{            TextView tv_title;            TextView tv_singer;        }    }}

附帶核心代碼中用到的Music類，自訂配接器用到的自訂布局很簡單，就兩個TextView，這裡略。

package com.example.pulltorefresh;public class Music {    private String title;    private String singer;    public String getTitle() {        return title;    }    public void setTitle(String title) {        this.title = title;    }    public String getSinger() {        return singer;    }    public void setSinger(String singer) {        this.singer = singer;    }    public Music(String title, String singer) {        this.title = title;        this.singer = singer;    }    public Music() {    }    }