Oppo
Show or Hide Week Numbers in Calendar auf Oppo
On Coloros, the calendar app ships with week numbers turned off. That is a setting inside the calendar itself, not something buried in the general system settings, which explains why the option is easy to miss.
To turn it on or off, open the calendar and follow this path: Tap on Calendar ➔ Open the Menu ➔ Tap on Settings ➔ Tap on General ➔ Enable or disable Show week number.
Once enabled, every monthly and weekly view gets a small number next to each row, showing the calendar week for that stretch of days. This is useful for anyone who plans around ISO week numbers, for example in shift schedules, school terms, or project deadlines.
If the toggle does not stick after switching apps, check whether you are using the built-in Oppo calendar or a separate Google Calendar app, since each app manages this setting independently.
Turning the option off again removes the numbers from every view immediately, no restart needed.