Questions about Sdk>=23 's Android version permissions

In the SDK23 is the Android6.0.1 to write the call system directory Read and Write permissions program, in Androidmanifest.xml, has been configured

<android:name= "Android.permission.READ_CONTACTS"/><  android:name= "Android.permission.WRITE_CONTACTS"/>

However, the exception still occurs in the run, as follows:

Java.lang.SecurityException:Permission denial:opening provider Com.android.providers.contacts.ContactsProvider2 From Processrecord (pid=28104, uid=10176) requires Android.permission.READ_CONTACTS or android.permission.WRITE_ CONTACTS

The reason is that SDK23 has made changes to application permissions, and there are two workarounds:
① is developed using SDK22, and the Android virtual machine that runs this program or the phone's system is under 6.0.

② before using Contentresolver, add the following code to verify the permissions.
The declaration of the Requestcode:request_code_ask_permissons constant is first performed.

Final Private int Request_code_ask_permissions = 123;

Before calling Contentresolver, check the permissions

 int  haswritecontactspermisson = Checkselfpermission (Android. Manifest.permission.READ_CONTACTS);  if  (Haswritecontactspermisson!= packagemanager.permission_granted) {Requestpermissions ( new   string[] {Manifest.permission.WRITE    _contacts}, Request_code_ask_permissions);  return  ;}  //  use Contentresolver to find contact data  Cursor cursor = Getcontentresolver (). Query (ContactsContract.Contacts.CONTENT_URI, null , null , null , null ); 

On the Xiaomi phone, the results of the operation:

Questions about Sdk>=23 's Android version permissions