android面试之contentProvider获取联系人

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getContacts();
}

private void getContacts() {
// 得到ContentResolver对象
ContentResolver cr = this.getContentResolver();
// 取得电话本中开始一项的光标,主要就是查询"contacts"表
Cursor cursor = cr.query(ContactsContract.Contacts.CONTENT_URI, null, null, null, null);
while (cursor.moveToNext())
{
StringBuilder sbLog = new StringBuilder();

// 取得联系人名字 (显示出来的名字)，实际内容在 ContactsContract.Contacts中
int nameIndex = cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME);
String name = cursor.getString(nameIndex);
sbLog.append("name=" + name + ";");

// 取得联系人ID
String contactId = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts._ID));

// 根据联系人ID查询对应的电话号码
Cursor phoneNumbers = cr.query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, ContactsContract.CommonDataKinds.Phone.CONTACT_ID + " = "
+ contactId, null, null);
// 取得电话号码(可能存在多个号码)
while (phoneNumbers.moveToNext())
{
String strPhoneNumber = phoneNumbers.getString(phoneNumbers.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
sbLog.append("Phone=" + strPhoneNumber + ";");
}
phoneNumbers.close();

// 根据联系人ID查询对应的email
Cursor emails = cr.query(ContactsContract.CommonDataKinds.Email.CONTENT_URI, null, ContactsContract.CommonDataKinds.Email.CONTACT_ID + " = "
+ contactId, null, null);
// 取得email(可能存在多个email)
while (emails.moveToNext())
{
String strEmail = emails.getString(emails.getColumnIndex(ContactsContract.CommonDataKinds.Email.DATA));
sbLog.append("Email=" + strEmail + ";");
}
emails.close();

Log.i("TAG", sbLog.toString());
}
cursor.close();
}

}