How to set the return key for oppok9?

oppok9 doesn't have a traditional mobile phone button, and friends who are used to using the back button need to set it themselves, so how does oppok9 set the back button? Let's take a look ~ How does OPPO K9 set the return button?

1. click convenient tools in the phone settings menu.

2. Click the navigation mode.

3. Check the virtual button.

4. Just choose a key layout method.

taking oppok9 as an example, this paper is suitable for ColorOS 11.1 system.