Swift：从信标唤醒开始 ble 扫描

Question

have an application that is wake by an ibeacon, the application is wake it starts a scan.

When the screen is off the scan not seem to work, that I turn on the screen the scan the scan return results. I understand the scan does not work if the screen is off. How to make Start Scan via Beacon advertisement?

I think before that worked, I am on ios 15. I did not check on iOS14, but on iOS 13 the scan worked when the screen was off, I just did not have access to advertisement data

Answer 1

In order to get bluetooth events in the background, you need to make sure your Info.plist declares this:

        <key>UIBackgroundModes</key>
        <array>
           <string>bluetooth-central</string>
        </array>

If that is not present, you absolutely will not get callbacks to didDiscoverPeripheral in the background.