列表视图以垂直列表的方式列出需要显示的列表项。
android:dividerHeight="30dp" 间隔高度
android:divider="@color/colorPrimary" 间距背景色
android:fadingEdge="vertical" 设置上下方阴影,none为无
android:scrollbars="horizontal" 值为horizontallvertical时显示滚动条
android:drawSelectorOnTop="false" 点击某条记录,颜色成为背景色
android:fastScrollEnabled="true" 快速滚动效果
android:listSelector="@color/colorPrimary" 选中时的颜色
android:entries="@array/city" 设置列表填充的内容
基础的使用
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginStart="0dp"
android:layout_marginTop="0dp"
android:id="@+id/listview"
android:dividerHeight="30dp"
android:divider="@color/colorBlue"
android:fadingEdge="vertical"
android:fastScrollEnabled="true"
android:listSelector="@color/colorPurple"
android:entries="@array/name"/>
//arrays.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<array name="name">
<item>贝贝</item>
<item>晶晶</item>
<item>欢欢</item>
<item>迎迎</item>
<item>妮妮</item>
</array>
</resources>
public class MainActivity_Listview extends AppCompatActivity {
private ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main__listview);
listView = (ListView)findViewById(R.id.listview);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
TextView tv=(TextView)view;
Toast.makeText(MainActivity_Listview.this,tv.getText(),Toast.LENGTH_SHORT).show();
}
});
}
}
ListActivity类的使用:
//不需要设置布局
public class MainActivity_listact extends ListActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ArrayAdapter arrayAdapter = ArrayAdapter.createFromResource(
this,R.array.name,android.R.layout.simple_list_item_1);
setListAdapter(arrayAdapter);
}
@Override
protected void onListItemClick(ListView l, View v,int position,long id){
Toast.makeText(this,((TextView)v).getText(),Toast.LENGTH_SHORT).show();
}
}
单选和多选的使用
public class MainActivity_lvch extends AppCompatActivity {
private ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_lvch);
listView = (ListView)findViewById(R.id.listview);
String[] arr = getResources().getStringArray(R.array.name);
//单选模式
ArrayAdapter<String> aa1 = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_single_choice,arr);
listView.setChoiceMode(ListView.CHOICE_MODE_SINGLE);
//多选模式
//ArrayAdapter<String> aa2 = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_multiple_choice,arr);
//listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
listView.setAdapter(aa1);
}
}
ListView实现图文列表
//list_item_sa.xml,作为每一项的布局使用,两个方式都需要
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:padding="16dp">
<ImageView
android:id="@+id/imageView_icon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:srcCompat="@android:drawable/btn_star_big_on" />
<TextView
android:id="@+id/textView_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"
android:layout_marginLeft="10dp"/>
</LinearLayout>
1)SimpleAdapter的使用
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class MainActivity_sa extends AppCompatActivity {
private ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_sa);
listView = (ListView)findViewById(R.id.listview);
//准备数据,每一个HashMap是一条记录
HashMap<String,Object> title1 = new HashMap<>();
title1.put("title","title-1");
title1.put("icon",android.R.drawable.star_big_off);
HashMap<String,Object> title2 = new HashMap<>();
title2.put("title","title-2");
title2.put("icon",android.R.drawable.star_on);
HashMap<String,Object> title3 = new HashMap<>();
title3.put("title","title-3");
title3.put("icon",android.R.drawable.star_big_on);
ArrayList<Map<String,Object>> list = new ArrayList<>();
list.add(title1);
list.add(title2);
list.add(title3);
//把数据填充到Adapter
SimpleAdapter sa = new SimpleAdapter(
this,list,R.layout.list_item_sa,new String[]{"title","icon"},new int[]{R.id.textView_title,R.id.imageView_icon});
listView.setAdapter(sa);
}
}
2)自定义Adapter
import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity_uda extends AppCompatActivity {
private ListView listView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_uda);
listView = (ListView)findViewById(R.id.listview);
listView.setAdapter(new MyAdapter(this));
}
static class MyAdapter extends BaseAdapter{
private String[] titles = {"title-1","title-2","title-3","title-4","title-5"};
private int[] icons = {android.R.drawable.btn_star,android.R.drawable.star_big_on,
android.R.drawable.btn_star_big_on,android.R.drawable.star_off,android.R.drawable.star_on};
private Context context;
public MyAdapter(Context context){
this.context = context;
}
@Override
public int getCount() {
return titles.length;
}
@Override
public Object getItem(int position) {
return titles[position];
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = LayoutInflater.from(context);
View view = inflater.inflate(R.layout.list_item_uda,null);
TextView tv_title = (TextView) view.findViewById(R.id.textView_title);
ImageView iv_icon = (ImageView) view.findViewById(R.id.imageView_icon);
tv_title.setText(titles[position]);
iv_icon.setImageResource(icons[position]);
return view;
}
}
}
优化:
1.使用convertView减少对象组件
if(convertView==null) {
LayoutInflater inflater = LayoutInflater.from(context);
//实例化一个布局文件
convertView = inflater.inflate(R.layout.list_item_uda,null);
}
System.out.println(position+"----"+convertView);
TextView tv_title = (TextView) convertView.findViewById(R.id.textView_title);
ImageView iv_icon = (ImageView) convertView.findViewById(R.id.imageView_icon);
tv_title.setText(titles[position]);
iv_icon.setImageResource(icons[position]);
return convertView;
2.View Holder优化
static class MyAdapter extends BaseAdapter{
private String[] titles = {"title-1","title-2","title-3","title-4","title-5",
"title-6","title-7","title-8","title-9","title-10",
"title-11","title-12","title-13"};
private int[] icons = {android.R.drawable.btn_star,android.R.drawable.star_big_on,
android.R.drawable.btn_star_big_on,android.R.drawable.star_off,
android.R.drawable.star_on,android.R.drawable.btn_star,
android.R.drawable.star_big_on, android.R.drawable.btn_star_big_on,
android.R.drawable.star_off, android.R.drawable.star_on,
android.R.drawable.btn_star,android.R.drawable.star_big_on,
android.R.drawable.btn_star_big_on};
private Context context;
public MyAdapter(Context context){
this.context = context;
}
@Override
public int getCount() {
return titles.length;
}
@Override
public Object getItem(int position) {
return titles[position];
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder vh;
if(convertView==null) {
LayoutInflater inflater = LayoutInflater.from(context);
//实例化一个布局文件
convertView = inflater.inflate(R.layout.list_item_uda,null);
vh = new ViewHolder();
vh.iv_icon = (ImageView)convertView.findViewById(R.id.imageView_icon);
TextView tv_title = (TextView)convertView.findViewById(R.id.textView_title);
convertView.setTag(vh);
}else {
vh = (ViewHolder) convertView.getTag();
}
vh.tv_title.setText(titles[position]);
vh.iv_icon.setImageResource(icons[position]);
return convertView;
}
//用于保存第一次查找的组件,避免下次重复查找
static class ViewHolder{
ImageView iv_icon;
TextView tv_title;
}
listView刷新分页
1.当前 Activity implements OnScrollListener
2.实现接口的方法
3.listView注册滚动监听
4.Adapter中添加增加数据的函数
5.获得2页以后的数据后,adapter增加数据,并刷新notifyDateSetChanged();
<!--activity_main_fy.xml-->
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity_fy">
<ListView
android:id="@+id/listview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true"/>
</RelativeLayout>
<!--list_item.fy.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:gravity="center_vertical"
android:padding="16px">
<TextView
android:id="@+id/textView_title"
android:layout_width="64dp"
android:layout_height="60dp"
android:layout_marginLeft="10dp"
android:text="title" />
<TextView
android:id="@+id/textView_content"
android:layout_width="100dp"
android:layout_height="60dp"
android:layout_marginLeft="10dp"
android:text="content" />
</LinearLayout>
<!--loading.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="horizontal"
android:gravity="center">
<ProgressBar
android:id="@+id/progressBar"
style="?android:attr/progressBarStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
<TextView
android:id="@+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="正在玩命加载数据..." />
</LinearLayout>
//MainActivity_fy.java
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;
import java.util.Vector;
public class MainActivity_fy extends AppCompatActivity implements AbsListView.OnScrollListener {
private ListView listView;
private Vector<News> news = new Vector<>();
private MyAdapter myAdapter;
private static final int DATA_UPDATE = 0x1;//数据更新完成后的标记
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_fy);
listView = (ListView) findViewById(R.id.listview);
listView.setOnScrollListener(this);
View footerView = getLayoutInflater().inflate(R.layout.loading,null);
listView.addFooterView(footerView);
initDate();
myAdapter = new MyAdapter();
listView.setAdapter(myAdapter);
}
private int index = 1;
/***
* 初始化数据
*/
private void initDate(){
for (int i=0;i<10;i++){
News n = new News();
n.title = "title--"+index;
n.content = "content--"+index;
index++;
news.add(n);
}
}
private int visibleLeastIndex;//用来可显示的最后一条数据d的索引
//状态改变,三个状态,fling,idl,touch_scroll
@Override
public void onScrollStateChanged(AbsListView view, int scrollState) {
if(myAdapter.getCount() == visibleLeastIndex && scrollState == AbsListView.OnScrollListener.SCROLL_STATE_IDLE){
new LoadDataThread().start();
}
}
@Override
public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
visibleLeastIndex = firstVisibleItem+visibleItemCount-1;
}
//线程之间通讯的机制
private Handler handler = new Handler() {
//处理消息
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case DATA_UPDATE:
myAdapter.notifyDataSetChanged();
break;
}
}
};
//模拟加载数据的线程
class LoadDataThread extends Thread{
@Override
public void run(){
initDate();
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
// myAdapter.notifyDataSetChanged();
//通过handler给主线程发送一个消息标记
handler.sendEmptyMessage(DATA_UPDATE);
}
}
class MyAdapter extends BaseAdapter{
@Override
public int getCount() {
return news.size();
}
@Override
public Object getItem(int position) {
return news.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder vh;
if(convertView==null){
convertView = getLayoutInflater().inflate(R.layout.list_item_fy,null);
vh = new ViewHolder();
vh.tv_title = (TextView) convertView.findViewById(R.id.textView_title);
vh.tv_content = (TextView) convertView.findViewById(R.id.textView_content);
convertView.setTag(vh);
}else {
vh = (ViewHolder)convertView.getTag();
}
News n = news.get(position);
vh.tv_title.setText(n.title);
vh.tv_content.setText(n.content);
return convertView;
}
class ViewHolder{
TextView tv_title;
TextView tv_content;
}
}
}
//news.java
public class News {
String title;
String content;
}