How to make oppo mobile phone fully charged with sound prompt?

Take OPPO R9S mobile phone as an example, the setting method is as follows:

First, find "Settings" on the phone desktop and click Enter.

2. After entering, find "Notification and Status Bar" and click Enter.

3. After entering, find "Notification Management" and click Enter.

4. After entering, find "Battery" and click Enter.

5. After entering, turn on the switch in the column of "ringtone and vibration notification", so that the ringtone and vibration will ring when the mobile phone is fully charged.