Xiaomi devices run a heavily customized version of Android (MIUI/HyperOS). This system uses very aggressive background restrictions and non-standard settings that can cause problems with notifications, widgets, or synchronization. Here is how to fix the most common issues.

1

Sync Issues & Missing Auto-Start Permission

In most cases, when notifications do not show up or tasks fail to sync on a Xiaomi phone, it is because of a special setting called Auto-Start:

How to fix it: Xiaomi blocks background actions by default unless you give the app explicit permission. Open your main device Settings → Apps → Permissions → Background autostart (or use the Security app → Permissions). Find aCalendar in the list and toggle the switch to ON. This ensures the system does not kill the app's background processes.

2

Background Color / Forced Dark Mode

If text colors look strange, illegible, or your event colors change unexpectedly, Xiaomi's built-in theme engine is overriding the app:

How to fix it: Xiaomi tries to force its own dark theme onto apps that do not ask for it, which ruins customized color palettes. Go to phone Settings → Display → More Dark mode options. Find aCalendar in the app list and turn the switch OFF. Instead, use aCalendar's built-in dark theme by going to aCalendar Settings → Design.

3

Inactive or Unresponsive Widgets

If you use a third-party home screen launcher (like Nova Launcher) and notice that tapping your calendar widget does nothing, a specific system block is active:

How to fix it: Go to device Settings → Apps → Manage apps → aCalendar → Other permissions. Locate the option named Display pop-up windows while running in the background and change it to Always allow. This is a known Xiaomi system bug that stops widgets from launching screens when background actions are restricted.

4

App Icon or Notification Style Issues

If your generic app icon is completely missing from your screen, or if event status icons look wrong in your status bar, try these quick changes:

✓

Missing App Icon

This is typically a known bug within Xiaomi's custom App Vault software. We highly recommend disabling App Vault entirely in your phone's Home Screen settings to bring back missing shortcuts.

✓

Wrong Notification Icons

If you see a generic app logo instead of specific event details, tasks, or dynamic date details in your drop-down bar, open system Settings → Notifications & Status bar. Find the Notification style setting and change it from MIUI to Android.