Android ListView数据的分批显示
布局文件activity_call_safe2.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" > <RelativeLayout android:layout_width="match_parent" android:layout_height="wrap_content" > <TextView style="@style/TitleStyle" android:text="黑名单管理" /> <Button android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:text="添加" /> </RelativeLayout> <FrameLayout android:layout_width="match_parent" android:layout_height="match_parent" android:layout_weight="11" > <LinearLayout android:id="@+id/ll_pb" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:visibility="invisible" android:orientation="vertical" > <ProgressBar android:layout_width="wrap_content" android:layout_height="wrap_content" /> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="玩命加载中..." /> </LinearLayout> <include android:id="@+id/list_view_callsafe" layout="@layout/list_view_callsafe"/> </FrameLayout> </LinearLayout>逻辑文件，实现页面的分页显示，监听ListView的滑动事件，滑动的时候就更新数据
CasllSafeActivity.java
package com.ldw.safe.Activity; import java.util.List; import android.app.Activity; import android.content.Context; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup; import android.widget.AbsListView; import android.widget.AbsListView.OnScrollListener; import android.widget.EditText; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.ListView; import android.widget.TextView; import android.widget.Toast; import com.ldw.safe.R; import com.ldw.safe.adapter.MyBaseAdapter; import com.ldw.safe.bean.BlackNumberInfo; import com.ldw.safe.db.dao.BlackNumberDao; public class CallSafeActivity extends Activity { private ListView list_view_callsafe; private List<BlackNumberInfo> blackNumberInfos; private LinearLayout ll_pb; private BlackNumberDao dao; private CallSafeAdapter adapter; private int totalNumber;//总的条数 private int mStartIndex = 0;//开始加载的位置 private int maxCount = 20;//每页加载多少数据 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_call_safe2); initUi(); initData(); } //初始化数据 private Handler handler = new Handler(){ @Override public void handleMessage(Message msg) { //数据初始化结束，关闭家在全的展示 ll_pb.setVisibility(View.INVISIBLE); //防止适配器一直刷新 if(adapter == null){ adapter = new CallSafeAdapter(blackNumberInfos, CallSafeActivity.this); //配置适配器 list_view_callsafe.setAdapter(adapter); }else{ adapter.notifyDataSetChanged(); } } }; private EditText et_page_number; //初始化数据 private void initData() { //防止阻塞主线程，在子线程中初始化数据（后期数据会很多） new Thread(){ @Override public void run(){ dao = new BlackNumberDao(CallSafeActivity.this); //一共有多少条数据 totalNumber = dao.getTotalNumber(); //分批加载数据 if(blackNumberInfos == null){ //第一次加载 blackNumberInfos = dao.findPar2(mStartIndex, maxCount); }else{ //把后面的数据。追加到blackNumberInfos集合里面。防止黑名单被覆盖 blackNumberInfos.addAll(dao.findPar2(mStartIndex, maxCount)); } handler.sendEmptyMessage(0); } }.start(); } //初始化UI private void initUi() { ll_pb = (LinearLayout) findViewById(R.id.ll_pb); //初始化的时候展示加载的圆圈 ll_pb.setVisibility(View.VISIBLE); list_view_callsafe = (ListView) findViewById(R.id.list_view_callsafe); //设置listView的滚动监听器 list_view_callsafe.setOnScrollListener(new OnScrollListener(){ //状态改变时候回调的方法 /* * @param scrollState 表示滚动的状态 *AbsListView.OnScrollListener.SCROLL_STATE_IDLE 闲置状态 *AbsListView.OnScrollListener.SCROLL_STATE_TOUCH_SCROLL 手指触摸的时候的状态 *AbsListView.OnScrollListener.SCROLL_STATE_FLING 惯性 */ @Override public void onScrollStateChanged(AbsListView view, int scrollState) { switch (scrollState) { case AbsListView.OnScrollListener.SCROLL_STATE_IDLE: //获取到最后一条显示的数据条数 int lastVisiblePosition = list_view_callsafe.getLastVisiblePosition(); System.out.println("lastVisiblePosition==========" + lastVisiblePosition); if(lastVisiblePosition == blackNumberInfos.size() - 1){//判断最后一个数据是不是每页显示的数据-1 // 加载更多的数据。 更改加载数据的开始位置 mStartIndex += maxCount; if (mStartIndex >= totalNumber) { Toast.makeText(getApplicationContext(), "没有更多的数据了。", Toast.LENGTH_SHORT).show(); return; } initData(); } break; } } //listview滚动的时候调用的方法 //时时调用。当我们的手指触摸的屏幕的时候就调用 @Override public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) { // TODO Auto-generated method stub } }); } //对代码进行优化，继承自定义MyBaseAdapter，MyBaseAdapter继承自BaseAdapter封装一些常用的方法 private class CallSafeAdapter extends MyBaseAdapter<BlackNumberInfo>{ private CallSafeAdapter(List lists, Context mContext){ super(lists, mContext); } @Override public View getView(int position, View convertView, ViewGroup parent) { //谷歌推出的优化方案 ViewHolder holder; if(convertView == null){ convertView = View.inflate(CallSafeActivity.this, R.layout.item_call_safe, null); holder = new ViewHolder(); holder.tv_number = (TextView) convertView.findViewById(R.id.tv_number); holder.tv_mode = (TextView) convertView.findViewById(R.id.tv_mode); holder.iv_delete = (ImageView) convertView.findViewById(R.id.iv_delete); convertView.setTag(holder); }else{ holder = (ViewHolder) convertView.getTag(); } holder.tv_number.setText(lists.get(position).getNumber()); String mode = lists.get(position).getMode(); if(mode.equals("1")){ holder.tv_mode.setText("电话和短信拦截"); }else if(mode.equals("2")){ holder.tv_mode.setText("电话拦截"); }else if(mode.equals("3")){ holder.tv_mode.setText("短信拦截"); } final BlackNumberInfo info = lists.get(position); //监听删除数据按钮，删除数据 holder.iv_delete.setOnClickListener(new OnClickListener(){ @Override public void onClick(View v) { String number = info.getNumber(); boolean result = dao.delete(number); if(result){ Toast.makeText(CallSafeActivity.this, "删除成功", Toast.LENGTH_SHORT).show(); lists.remove(info); //更新ListView adapter.notifyDataSetChanged(); }else{ Toast.makeText(CallSafeActivity.this, "删除失败", Toast.LENGTH_SHORT).show(); } } }); return convertView; /* //谷歌推出的优化方案 ViewHolder holder; if(convertView == null){ convertView = View.inflate(CallSafeActivity.this, R.layout.item_call_safe, null); holder = new ViewHolder(); holder.tv_number = (TextView) convertView.findViewById(R.id.tv_number); holder.tv_mode = (TextView) convertView.findViewById(R.id.tv_mode); convertView.setTag(holder); }else{ holder = (ViewHolder) convertView.getTag(); } holder.tv_number.setText(blackNumberInfos.get(position).getNumber()); String mode = blackNumberInfos.get(position).getMode(); if(mode.equals("1")){ holder.tv_mode.setText("电话和短信拦截"); }else if(mode.equals("2")){ holder.tv_mode.setText("电话拦截"); }else if(mode.equals("3")){ holder.tv_mode.setText("短信拦截"); } return convertView; */ /*初步的优化 convertView = View.inflate(CallSafeActivity.this, R.layout.item_call_safe, null); TextView tv_number = (TextView) convertView.findViewById(R.id.tv_number); TextView tv_mode = (TextView) convertView.findViewById(R.id.tv_mode); tv_number.setText(blackNumberInfos.get(position).getNumber()); String mode = blackNumberInfos.get(position).getMode(); if(mode.equals("1")){ tv_mode.setText("电话和短信拦截"); }else if(mode.equals("2")){ tv_mode.setText("电话拦截"); }else if(mode.equals("3")){ tv_mode.setText("短信拦截"); } return convertView; */ /*传统的方式 View view = View.inflate(CallSafeActivity.this, R.layout.item_call_safe, null); TextView tv_number = (TextView) view.findViewById(R.id.tv_number); TextView tv_mode = (TextView) view.findViewById(R.id.tv_mode); tv_number.setText(blackNumberInfos.get(position).getNumber()); String mode = blackNumberInfos.get(position).getMode(); if(mode.equals("1")){ tv_mode.setText("电话和短信拦截"); }else if(mode.equals("2")){ tv_mode.setText("电话拦截"); }else if(mode.equals("3")){ tv_mode.setText("短信拦截"); } return view; */ } } static class ViewHolder{ TextView tv_number; TextView tv_mode; ImageView iv_delete; } }
以上所述是小编给大家介绍的Android ListView数据的分批显示功能，希望对大家有所帮助，如果大家有任何疑问欢迎给我留言，小编会及时回复大家的！