If an application that uses QNetworkAccessManager loses Internet access through its Wi-Fi connection, then it fails to use the cellular link to access Internet.
Steps to reproduce:
- Build attached minimal project
- Make sure you have Wi-Fi connected to Internet AND cellular activated
- Start app > click "ping" > you should see something downloaded
- Disable Wi-Fi from the device settings
- Variant: switch to another Wi-Fi with no Internet access
- Return to app > click "ping" > cannot access Internet despite cellular connection
Note: if you can't reproduce this issue, try to enable/disable the Wi-Fi a few times and retry. Restarting the device seems to momentarily fix the issue.
Note 2: if you start the app with Wi-Fi disabled, it can access Internet with cellular.
Android seems not affected by this.
The above-mentioned issues relate to the QNAM not restoring Internet access after Wi-Fi was disabled and then re-enabled. My issue is different: it's Qt not switching to cellular when there is no more Internet access through Wi-Fi.
QTBUG-40332 High ping when QNetworkAccessManager is instantiated