使用Contacts Contract Content Provider操作通讯录最佳实践

Android向所有被赋予READ_CONTACTS权限的应用程序提供了联系人信息数据库的完全访问权限。Contacts Contract使用3层数据模型去存储数据，下面介绍Contacts Contract的子类：
1.Data 表中的每行都定义了个人的数据集（电话号码，email地址，等等），用MIME类型区分开。尽管有为每个个人数据的类型预定义可用的列名（ContactsContract.CommonDataKinds里装有合适的MIME类型），此表能被用来存储任何值。
当向Data表中加入数据的时候，你需要指定与数据集相关的Raw Contact。
2.RawContacts 从Android 2.0（API 5）向前，用户可以增加多个联系人账户的Provider。RawContacts表中的每行定义了一个与数据集相关的账户。说白了就是账户信息。

3.Contacts Contacts表的行聚合了RawContacts中的数据，每行代表了不同的人信息。

读取联系人详情：

首先在庆典文件中添加权限：<uses-permission android:name=”android.permission.READ_CONTACTS”/>

然后是访问Contacts Contract Content Provider：

private String[] getNames() {    /**     * Listing 8-36: Accessing the Contacts Contract Contact Content Provider     */    // Create a projection that limits the result Cursor    // to the required columns.    String[] projection = {      ContactsContract.Contacts._ID,      ContactsContract.Contacts.DISPLAY_NAME    };     // Get a Cursor over the Contacts Provider.    Cursor cursor =       getContentResolver().query(ContactsContract.Contacts.CONTENT_URI,                                 projection, null, null, null);           // Get the index of the columns.    int nameIdx =       cursor.getColumnIndexOrThrow(ContactsContract.Contacts.DISPLAY_NAME);    int idIdx =       cursor.getColumnIndexOrThrow(ContactsContract.Contacts._ID);      // Initialize the result set.    String[] result = new String[cursor.getCount()];      // Iterate over the result Cursor.    while(cursor.moveToNext()) {      // Extract the name.      String name = cursor.getString(nameIdx);      // Extract the unique ID.      String id = cursor.getString(idIdx);         result[cursor.getPosition()] = name + " (" + id + ")";    }       // Close the Cursor.    cursor.close();    //    return result;  }

找到联系人姓名的联系信息：

 private String[] getNameAndNumber() {    /**     * Listing 8-37: Finding contact details for a contact name     */    ContentResolver cr = getContentResolver();    String[] result = null;    // Find a contact using a partial name match    String searchName = "andy";    Uri lookupUri =       Uri.withAppendedPath(ContactsContract.Contacts.CONTENT_FILTER_URI,                           searchName);    // Create a projection of the required column names.    String[] projection = new String[] {      ContactsContract.Contacts._ID    };    // Get a Cursor that will return the ID(s) of the matched name.    Cursor idCursor = cr.query(lookupUri,       projection, null, null, null);    // Extract the first matching ID if it exists.    String id = null;    if (idCursor.moveToFirst()) {      int idIdx =         idCursor.getColumnIndexOrThrow(ContactsContract.Contacts._ID);      id = idCursor.getString(idIdx);    }    // Close that Cursor.    idCursor.close();    // Create a new Cursor searching for the data associated with the returned Contact ID.    if (id != null) {      // Return all the PHONE data for the contact.      String where = ContactsContract.Data.CONTACT_ID +         " = " + id + " AND " +        ContactsContract.Data.MIMETYPE + " = '" +        ContactsContract.CommonDataKinds.Phone.CONTENT_ITEM_TYPE +        "'";      projection = new String[] {        ContactsContract.Data.DISPLAY_NAME,        ContactsContract.CommonDataKinds.Phone.NUMBER      };            Cursor dataCursor =         getContentResolver().query(ContactsContract.Data.CONTENT_URI,          projection, where, null, null);      // Get the indexes of the required columns.      int nameIdx =         dataCursor.getColumnIndexOrThrow(ContactsContract.Data.DISPLAY_NAME);      int phoneIdx =         dataCursor.getColumnIndexOrThrow(          ContactsContract.CommonDataKinds.Phone.NUMBER);      result = new String[dataCursor.getCount()];            while(dataCursor.moveToNext()) {        // Extract the name.        String name = dataCursor.getString(nameIdx);        // Extract the phone number.        String number = dataCursor.getString(phoneIdx);        result[dataCursor.getPosition()] = name + " (" + number + ")";      }            dataCursor.close();    }        return result;  }

Contacts子类还提供了电话号码查找URI，用来帮助找到与特定电话号码相关的联系人，执行呼叫者ID查找：

private String performCallerId() {    /**     * Listing 8-38: Performing a caller-ID lookup     */    String incomingNumber = "[phone]";    String result = "Not Found";    Uri lookupUri =      Uri.withAppendedPath(ContactsContract.PhoneLookup.CONTENT_FILTER_URI,                           incomingNumber);    String[] projection = new String[] {      ContactsContract.Contacts.DISPLAY_NAME    };    Cursor cursor = getContentResolver().query(lookupUri,      projection, null, null, null);    if (cursor.moveToFirst()) {      int nameIdx =         cursor.getColumnIndexOrThrow(ContactsContract.Contacts.DISPLAY_NAME);            result = cursor.getString(nameIdx);    }    cursor.close();        return result;  }

使用Intent创建和选择联系人，这是一种最佳的实践做法，其优势在于用户在执行相同任务的时候看到的一致的界面，这可以避免用户感到混淆，并且改善用户体验，下面是悬着一个联系人：

  private static int PICK_CONTACT = 0;  private void pickContact() {    Intent intent = new Intent(Intent.ACTION_PICK,                               ContactsContract.Contacts.CONTENT_URI);      startActivityForResult(intent, PICK_CONTACT);    }

当选择好之后，作为返回Intent的data属性内的URI返回：

@Override  protected void onActivityResult(int requestCode, int resultCode, Intent data) {    super.onActivityResult(requestCode, resultCode, data);    if ((requestCode == PICK_CONTACT) && (resultCode == RESULT_OK)) {      resultTextView.setText(data.getData().toString());    }  }

插入新联系人：，当然这需要一个权限：

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

之后就可以插入联系人啦！

Intent intent =       new Intent(ContactsContract.Intents.SHOW_OR_CREATE_CONTACT,                 ContactsContract.Contacts.CONTENT_URI);    intent.setData(Uri.parse("tel:[phone]"));    intent.putExtra(ContactsContract.Intents.Insert.COMPANY, "Google");    intent.putExtra(ContactsContract.Intents.Insert.POSTAL,       "1600 Amphitheatre Parkway, Mountain View, California");    startActivity(intent);