Android permission doesn't work even if I have declared it

_{(the following is extracted from a blog post of mine about this)}

The big reason for not getting your permission nowadays is because your project has a targetSdkVersion of 23 or higher, and the permission that you are requesting is "dangerous". In Android 6.0, this includes:

• ACCEPT_HANDOVER
• ACCESS_BACKGROUND_LOCATION
• ACCESS_MEDIA_LOCATION
• ACTIVITY_RECOGNITION
• ANSWER_PHONE_CALLS
• ACCESS_COARSE_LOCATION
• ACCESS_FINE_LOCATION
• ADD_VOICEMAIL
• BODY_SENSORS
• CALL_PHONE
• CAMERA
• GET_ACCOUNTS
• PROCESS_OUTGOING_CALLS
• READ_CALENDAR
• READ_CALL_LOG
• READ_CELL_BROADCASTS
• READ_CONTACTS
• READ_EXTERNAL_STORAGE
• READ_PHONE_STATE
• READ_SMS
• RECEIVE_MMS
• RECEIVE_SMS
• RECEIVE_WAP_PUSH
• RECORD_AUDIO
• SEND_SMS
• USE_SIP
• WRITE_CALENDAR
• WRITE_CALL_LOG
• WRITE_CONTACTS
• WRITE_EXTERNAL_STORAGE

For these permissions, not only does your targetSdkVersion 23+ app need to have the <uses-permission> element(s), but you also have to ask for those permissions at runtime from the user on Android 6.0+ devices, using methods like checkSelfPermission() and requestPermissions().

As a temporary workaround, drop your targetSdkVersion below 23.

However, eventually, you will have some reason to want your targetSdkVersion to be 23 or higher. At that time, you will need to adjust your app to use the new runtime permission system. The Android documentation has a page dedicated to this topic.

Above API level 23 you will be given programmatically pragmatically like:

    private static final int PERMISSION_REQUEST_CODE = 1;

    if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.M) {

        if (checkSelfPermission(Manifest.permission.SEND_SMS)
                == PackageManager.PERMISSION_DENIED) {

            Log.d("permission", "permission denied to SEND_SMS - requesting it");
            String[] permissions = {Manifest.permission.SEND_SMS};

            requestPermissions(permissions, PERMISSION_REQUEST_CODE);

        }
    }

request permission pragmatically (after API 23)

if (ContextCompat.checkSelfPermission(thisActivity, Manifest.permission.SEND_SMS)
    != PackageManager.PERMISSION_GRANTED) {
    // Permission is not granted 
    // Ask for permision
    ActivityCompat.requestPermissions(this,new String[] { Manifest.permission.SEND_SMS}, 1); 
} 
else {
// Permission has already been granted
}

"If the app has the permission, the method checkSelfPermission() returns PERMISSION_GRANTED, and the app can proceed with the operation.

If the app does not have the permission, the method returns PERMISSION_DENIED, and the app has to explicitly ask the user for permission. You need to prompt the user for that permission, as shown in the above code. Calling requestPermissions() brings up a standard Android dialog, which you cannot customize."