20 Simple Content Provider Example

AndroidManifest.xml 

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.aslam.contentproviderexample2" >
<uses-permission android:name="android.permission.READ_CONTACTS" />
    <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>

activity_main.xml

<?xml version="1.0" encoding="utf-8"?> 

<android.support.constraint.ConstraintLayout 

   xmlns:android="http://schemas.android.com/apk/res/android" 

   xmlns:tools="http://schemas.android.com/tools" 

   xmlns:app="http://schemas.android.com/apk/res-auto" 

   android:layout_width="match_parent" 

   android:layout_height="match_parent" 

   tools:context=".MainActivity">

<TextView 

    android:layout_width="wrap_content" 

    android:layout_height="wrap_content" 

    android:text="Hello World!" 

    app:layout_constraintBottom_toBottomOf="parent" 

    app:layout_constraintLeft_toLeftOf="parent" 

    app:layout_constraintRight_toRightOf="parent" 

    app:layout_constraintTop_toTopOf="parent" />

<ListView        

   android:id="@+id/list_view" 

   android:layout_width="wrap_content" 

   android:layout_height="wrap_content"/>

</android.support.constraint.ConstraintLayout>

MainActivity.java 

import android.Manifest;
import android.database.Cursor;
import android.provider.ContactsContract;
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {
    ListView listView;
    ArrayList al=new ArrayList();
    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.READ_CONTACTS},1);
        listView=(ListView)findViewById(R.id.list_view);

        Cursor cursor=getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,null,null,null,null);

         while (cursor.moveToNext()){
             String name= cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
            al.add(name);
         }
         listView.setAdapter(new ArrayAdapter(MainActivity.this,android.R.layout.simple_list_item_1,al));
    }
}