添加读取联系人权限<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);
        //验证授权 仅支持6.x以上
        if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.READ_CONTACTS )== PackageManager.PERMISSION_DENIED){
            //请求权限
            ActivityCompat.requestPermissions(MainActivity.this, new String[]{Manifest.permission.READ_CONTACTS}, 123);
        }else {
            PrintContacts();
        }
    }
    //权限请求结果
    @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();
                }
        }
    }
    //打印联系人
    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();
            }
        }
    }
}

要到手机或模拟器上直接设置给这个应用读取联系人的权限，新系统是这样的

权限问题啊。

权限的问题吧