Android ContentProvider实现获取手机联系人功能

package com.example.content;  import android.content.ContentResolver; import android.database.Cursor; import android.net.Uri; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.util.Log; import android.view.View;  public class MainActivity extends AppCompatActivity {   private ContentResolver cr;   @Override  protected void onCreate(Bundle savedInstanceState) {   super.onCreate(savedInstanceState);   setContentView(R.layout.activity_main);   //获取内容访问者   cr = getContentResolver();  }  public void getContacts(View view){   Uri uri=Uri.parse("content://com.android.contacts/raw_contacts");   Cursor cursor=cr.query(uri,null,null,null,null);   while(cursor.moveToNext()){    int _id=cursor.getInt(cursor.getColumnIndex("_id"));    String display_name=cursor.getString(cursor.getColumnIndex("display_name"));    Log.i("test",_id+" "+display_name);    Uri uriData=Uri.parse("content://com.android.contacts/raw_contacts/"+_id+"/data");    Cursor cursorData=cr.query(uriData,null,null,null,null);    while(cursorData.moveToNext()){     String mimetype=cursorData.getString(cursorData.getColumnIndex("mimetype"));     String data1=cursorData.getString(cursorData.getColumnIndex("data1"));     if("vnd.android.cursor.item/phone_v2".equals(mimetype)){      Log.i("test","  "+mimetype+" "+data1);     }    }   }  } } 

<?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="match_parent" tools:context="com.example.content.MainActivity">   <Button   android:layout_width="wrap_content"   android:layout_height="wrap_content"   android:text="获取手机联系人"   android:onClick="getContacts"   />  </LinearLayout> 

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.example.content">   <!--获取手机的联系人-->  <uses-permission android:name="android.permission.READ_CONTACTS"></uses-permission>   <application android:allowBackup="true" android:icon="@mipmap/ic_launcher"   android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round"   android:supportsRtl="true" android:theme="@style/AppTheme">   <activity android:name=".MainActivity">    <intent-filter>     <action android:name="android.intent.action.MAIN" />      <category android:name="android.intent.category.LAUNCHER" />    </intent-filter>   </activity>  </application>  </manifest>