在开发中,我们经常使用到ListView这个控件。Android的AdivI也提供了许多创建ListView适配器的快捷方式。例如ArrayAdadivter、SimdivleAdadivter和SimdivleCursorAdadivter等。但你是否发现,如果采用这些系统自带的适配器,对于事件的响应只能局限在一个行单位。假设一行里面有一个按钮和一个图片控件,它们之间的响应操作是不一样的。若采用系统自带的适配器,就不能精确到每个控件的响应事件。这时,我们一般采取自定义适配器来实现这个比较精确地请求。
ListView的创建,一般要具备两大元素:
1)数据集,即要映射的字符串、图片信息之类。
2)适配器,实现把要映射的字符串、图片信息映射成视图(如Textview、Image等组件),再添加到ListView中。
一、实现细节:
下面是一个实操例子:
1、创建数据集,一般定义如下
private ArrayList<Contacts> contacts = new ArrayList<Contacts>();
2、创建适配器
public class MyListAdapter extends BaseAdapter {
private ArrayList<Contacts> contacts = null;
private Context mContext = null;
public MyListAdapter(ArrayList<Contacts> contacts,Context mContext) {
super();
this.contacts = contacts;
this.mContext = mContext;
}
......
}
3、将适配器绑定到ListView控件
myAdapter = new MyListAdapter(contacts,this);
setListAdapter(myAdapter);
4、将R.layout.item布局作为一个视图,添加到listView中:
ListItemView listItemView = new ListItemView();
if (convertView == null || position < contacts.size()) {
convertView = LayoutInflater.from(mContext).inflate(R.layout.item, null);
listItemView.iamge = (ImageView) convertView.findViewById(R.id.color_image);
listItemView.title = (TextView) convertView.findViewById(R.id.color_title);
listItemView.text = (TextView) convertView.findViewById(R.id.color_text);
convertView.setTag(listItemView);
}else{
listItemView = (ListItemView) convertView.getTag();
}
二、实例源码:
AndroidManifest.xml
<!-- 读取联系*限 -->
<uses-permission android:name="android.permission.READ_CONTACTS" />
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: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" >
<ListView
android:id="@android:id/list"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
</ListView>
</RelativeLayout>
item.xml
<?xml version="1.0" encoding="UTF-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content" >
<ImageView
android:id="@+id/color_image"
android:layout_width="40dip"
android:layout_height="40dip" />
<TextView
android:id="@+id/color_title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_toRightOf="@+id/color_image"
android:ellipsize="marquee"
android:singleLine="true"
android:textSize="15dip"
android:text="andy" />
<TextView
android:id="@+id/color_text"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/color_title"
android:layout_toRightOf="@+id/color_image"
android:ellipsize="marquee"
android:singleLine="true"
android:textSize="20dip"
android:text="1234567890" />
</RelativeLayout>
Contacts.java
package com.andieguo.listcontacts;
import android.graphics.Bitmap;
public class Contacts {
private String name;
private String number;
private Bitmap photo;
public Contacts(String name, String number, Bitmap photo) {
super();
this.name = name;
this.number = number;
this.photo = photo;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getNumber() {
return number;
}
public void setNumber(String number) {
this.number = number;
}
public Bitmap getPhoto() {
return photo;
}
public void setPhoto(Bitmap photo) {
this.photo = photo;
}
}
MyListAdapter.java
package com.andieguo.listcontacts;
import java.util.ArrayList;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class MyListAdapter extends BaseAdapter {
private ArrayList<Contacts> contacts = null;
private Context mContext = null;
public MyListAdapter(ArrayList<Contacts> contacts,Context mContext) {
super();
this.contacts = contacts;
this.mContext = mContext;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return contacts.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public final class ListItemView {//提供缓存
public ImageView iamge = null;
public TextView title = null;
public TextView text = null;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ListItemView listItemView = new ListItemView();
if (convertView == null || position < contacts.size()) {
convertView = LayoutInflater.from(mContext).inflate(R.layout.item, null);
listItemView.iamge = (ImageView) convertView.findViewById(R.id.color_image);
listItemView.title = (TextView) convertView.findViewById(R.id.color_title);
listItemView.text = (TextView) convertView.findViewById(R.id.color_text);
convertView.setTag(listItemView);
}else{
listItemView = (ListItemView) convertView.getTag();
}
//绘制联系人名称
listItemView.title.setText(contacts.get(position).getName());
//绘制联系人号码
listItemView.text.setText(contacts.get(position).getNumber());
//绘制联系人头像
listItemView.iamge.setImageBitmap(contacts.get(position).getPhoto());
return convertView;
}
}
MainActivity.java
package com.andieguo.listcontacts;
import java.io.InputStream;
import java.util.ArrayList;
import android.net.Uri;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.provider.ContactsContract.CommonDataKinds.Phone;
import android.provider.ContactsContract.CommonDataKinds.Photo;
import android.app.ListActivity;
import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.text.TextUtils;
import android.view.Menu;
import android.widget.ListView;
public class MainActivity extends ListActivity {// 需要在main.xml文件中<ListView android:id="@android:id/list"></ListView>
/** 获取库Phon表字段 **/
private static final String[] PHONES_PROJECTION = new String[] {
Phone.DISPLAY_NAME, Phone.NUMBER, Photo.PHOTO_ID, Phone.CONTACT_ID };
/** 联系人显示名称 **/
private static final int PHONES_DISPLAY_NAME_INDEX = 0;
/** 电话号码 **/
private static final int PHONES_NUMBER_INDEX = 1;
/** 头像ID **/
private static final int PHONES_PHOTO_ID_INDEX = 2;
/** 联系人的ID **/
private static final int PHONES_CONTACT_ID_INDEX = 3;
private ArrayList<Contacts> contacts = new ArrayList<Contacts>();
private ListView mListView = null;
private MyListAdapter myAdapter = null;
private Context mContext = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mContext = this;
mListView = this.getListView();
/** 得到手机通讯录联系人信息 **/
getPhoneContacts();
myAdapter = new MyListAdapter(contacts,this);
setListAdapter(myAdapter);
}
private void getPhoneContacts() {
// TODO Auto-generated method stub
ContentResolver resolver = mContext.getContentResolver();
// 获取手机联系人
Cursor phoneCursor = resolver.query(Phone.CONTENT_URI,PHONES_PROJECTION, null, null, null);
if (phoneCursor != null) {
while (phoneCursor.moveToNext()) {
//得到手机号码
String phoneNumber = phoneCursor.getString(PHONES_NUMBER_INDEX);
//当手机号码为空的或者为空字段 跳过当前循环
if (TextUtils.isEmpty(phoneNumber))
continue;
//得到联系人名称
String contactName = phoneCursor.getString(PHONES_DISPLAY_NAME_INDEX);
//得到联系人ID
Long contactid = phoneCursor.getLong(PHONES_CONTACT_ID_INDEX);
//得到联系人头像ID
Long photoid = phoneCursor.getLong(PHONES_PHOTO_ID_INDEX);
//得到联系人头像Bitamp
Bitmap contactPhoto = null;
//photoid 大于0 表示联系人有头像 如果没有给此人设置头像则给他一个默认的
if(photoid > 0 ) {
Uri uri =ContentUris.withAppendedId(ContactsContract.Contacts.CONTENT_URI,contactid);
InputStream input = ContactsContract.Contacts.openContactPhotoInputStream(resolver, uri);
contactPhoto = BitmapFactory.decodeStream(input);
}else {
contactPhoto = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
}
Contacts contact = new Contacts(contactName, phoneNumber, contactPhoto);
contacts.add(contact);
}
phoneCursor.close();
}
}
@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;
}
}
参考:
Android之自定义Adapter的ListView