访问系统内容提供器，获取联系人列表

1：Contact.java

package com.example.bean;

public class Contact {
    private String name;
    private String phoneNumber;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getPhoneNumber() {
        return phoneNumber;
    }
    public void setPhoneNumber(String phoneNumber) {
        this.phoneNumber = phoneNumber;
    }
    
}

2：list_contact_item.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" 
    android:layout_margin="16dp">
    
    <TextView 
        android:id="@+id/tvContactName"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="18sp"
        android:singleLine="true"
        android:ellipsize="end"/>
    <TextView 
        android:id="@+id/tvContactPhoneNumber"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:textSize="16sp"
        android:singleLine="true"
        android:ellipsize="end"/>
</LinearLayout>

3：ContactAdapter.java

package com.example.adapter;

import java.util.List;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import com.example.bean.Contact;
import com.example.contacttest.R;

public class ContactAdapter extends ArrayAdapter<Contact>{
    int resourceId;
    
    public ContactAdapter(Context context, int resourceId, List<Contact> list){
        super(context,resourceId,list);
        this.resourceId = resourceId;
    }
    
    
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        Contact contact = getItem(position);
        View view;
        ViewHolder holder;
        
        if(convertView==null){
            view = LayoutInflater.from(getContext()).inflate(resourceId, null);
            holder = new ViewHolder();
            
            holder.tvContactName = (TextView)view.findViewById(R.id.tvContactName);
            holder.tvContactPhoneNumber = (TextView)view.findViewById(R.id.tvContactPhoneNumber);
            
            holder.tvContactName.setText(contact.getName());
            holder.tvContactPhoneNumber.setText(contact.getPhoneNumber());
            
            view.setTag(holder);
        }else{
            view = convertView;
            holder = (ViewHolder)view.getTag();
        }
        
        return view;
    }
    
    class ViewHolder{
        TextView tvContactName;
        TextView tvContactPhoneNumber;
    }
}

4：MainActivity.java

package com.example.contacttest;

import java.util.ArrayList;
import java.util.List;

import android.app.Activity;
import android.database.Cursor;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.widget.ListView;

import com.example.adapter.ContactAdapter;
import com.example.bean.Contact;

public class MainActivity extends Activity {
    
    List<Contact> list = null;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        setContentView(R.layout.activity_main);
        
        list = new ArrayList<Contact>();
        ListView lvContact = (ListView)findViewById(R.id.lvContact);
        ContactAdapter adapter = new ContactAdapter(this, R.layout.list_contact_item, list);
        lvContact.setAdapter(adapter);
        
        getContacts();
    }
    
    void getContacts(){
        Cursor cursor = null;
        
        try{
            cursor = getContentResolver().query(
                    ContactsContract.CommonDataKinds.Phone.CONTENT_URI, 
                    null, null, null, null);
            if(cursor!=null){
                Contact contact;
                while(cursor.moveToNext()){
                    contact = new Contact();
                    contact.setName(cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME)));
                    contact.setPhoneNumber(cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER)));
                    list.add(contact);
                }
                
                
            }
        }catch(Exception e){
            e.printStackTrace();
        }finally{
            if(cursor!=null){
                cursor.close();
            }
        }
        
    }
}

5：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: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="com.example.contacttest.MainActivity$PlaceholderFragment" >

    <ListView 
        android:id="@+id/lvContact"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

</RelativeLayout>

6：声明权限

<uses-permission android:name="android.permission.READ_CONTACTS"/>