添加讀取聯系人權限<uses-permission ? ? android.permission.READ_CONTACTS/>

public?class?MainActivity?extends?AppCompatActivity?{

????@Override
????protected?void?onCreate(Bundle?savedInstanceState)?{
????????super.onCreate(savedInstanceState);
????????setContentView(R.layout.activity_main);
????????//驗證授權?僅支持6.x以上
????????if?(ContextCompat.checkSelfPermission(MainActivity.this,?Manifest.permission.READ_CONTACTS?)==?PackageManager.PERMISSION_DENIED){
????????????//請求權限
????????????ActivityCompat.requestPermissions(MainActivity.this,?new?String[]{Manifest.permission.READ_CONTACTS},?123);
????????}else?{
????????????PrintContacts();
????????}
????}
????//權限請求結果
????@Override
????public?void?onRequestPermissionsResult(int?requestCode,?@NonNull?String[]?permissions,?@NonNull?int[]?grantResults)?{
????????super.onRequestPermissionsResult(requestCode,?permissions,?grantResults);

????????switch?(requestCode){
????????????case?123:
????????????????if?(grantResults[0]?==?PackageManager.PERMISSION_GRANTED)?{
???????????????????PrintContacts();
????????????????}
????????}
????}
????//打印聯系人
????private?void?PrintContacts?(){
????????ContentResolver?cr?=?getContentResolver();
????????Cursor?cursor?=?cr.query(ContactsContract.Contacts.CONTENT_URI,?new?String[]{Contacts._ID,?Contacts.DISPLAY_NAME,
????????},?null,null,null);

????????if(cursor!=null?&&cursor.moveToFirst()){
????????????while?(!cursor.isAfterLast()){
????????????????Log.i("info",?cursor.getString(cursor.getColumnIndex(Contacts._ID))+"---"+
????????????????????????cursor.getString(cursor.getColumnIndex(Contacts.DISPLAY_NAME)));

????????????????cursor.moveToNext();
????????????}
????????}
????}
}

要到手機或模擬器上直接設置給這個應用讀取聯系人的權限，新系統是這樣的

權限問題啊。

權限的問題吧