Run-time permissions in Android get contact information Demo

The code is relatively simple ...

Androidmanifest.xml

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="club.seliote.readcontact">     <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: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="club.seliote.readcontact.MainActivity">     <TextView        android:id="@+id/text_view"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="Unknow Data"        android:scrollbars="vertical"        app:layout_constraintBottom_toBottomOf="parent"        app:layout_constraintLeft_toLeftOf="parent"        app:layout_constraintRight_toRightOf="parent"        app:layout_constraintTop_toTopOf="parent" /> </android.support.constraint.ConstraintLayout>

Mainactivity.java

Package club.seliote.readcontact; Import Android. Manifest;import Android.content.contentresolver;import Android.content.pm.packagemanager;import Android.database.cursor;import Android.provider.contactscontract;import Android.support.annotation.NonNull; Import Android.support.v4.app.activitycompat;import Android.support.v4.content.contextcompat;import Android.support.v7.app.appcompatactivity;import Android.os.bundle;import Android.text.method.scrollingmovementmethod;import Android.widget.textview;import Android.widget.Toast; Import Java.util.hashmap;import Java.util.Map; public class Mainactivity extends appcompatactivity {@Override protected void onCreate (Bundle savedinstancestate)        {super.oncreate (savedinstancestate);         This.setcontentview (R.layout.activity_main);         map<string, string> contacts = null; if (Contextcompat.checkselfpermission (Mainactivity.this, Manifest.permission.READ_CONTACTS)! = packagemanager.permission_granted) {ACTIvitycompat.requestpermissions (Mainactivity.this, New string[]{manifest.permission.read_contacts}, 0);        } else {contacts = Readcontact ();         } String displaystring = "username:phonenumber\n\n"; if (contacts! = null &&!contacts.isempty ()) {for (map.entry<string, string> entry:contacts.en            Tryset ()) {displaystring + = Entry.getkey () + ":" + entry.getvalue () + "\ n";        }} TextView TextView = (TextView) This.findviewbyid (R.id.text_view);        Textview.setmovementmethod (Scrollingmovementmethod.getinstance ());    Textview.settext (displaystring);         } private Map<string, string> readcontact () {map<string, string> contacts = new hashmap<> (); Try (Cursor cursor = MainActivity.this.getContentResolver (). Query (ContactsContract.CommonDataKinds.Phone.CONTENT_U            RI, NULL, NULL, NULL, NULL)) {Cursor.movetofirst (); while (!cursor.isaFterlast ()) {String userName = cursor.getstring (Cursor.getcolumnindex (ContactsContract.CommonDataKinds.Pho Ne.                Display_name));                String phonenum = cursor.getstring (Cursor.getcolumnindex (ContactsContract.CommonDataKinds.Phone.NUMBER));                Contacts.put (UserName, phonenum);            Cursor.movetonext ();        }} catch (SecurityException exp) {exp.printstacktrace ();    } return contacts; } @Override public void Onrequestpermissionsresult (int requestcode, @NonNull string[] permissions, @NonNull int[] G        Rantresults) {Super.onrequestpermissionsresult (Requestcode, permissions, grantresults); Switch (requestcode) {case 0:if (permissions[0] = = Manifest.permission.READ_CONTACTS &&am P                Grantresults[0] = = packagemanager.permission_granted) {readcontact (); } else {Toast.maketext (mainactivity.this, "Permisson Deny! ", Toast.length_long). Show ();            } break;        Default:break; }    }}

Run-time permissions in Android get contact information Demo