When I turn off the Bluetooth connection, it does not turn into a red (list picker) why?

[Taifun]

see the answer here

Bluetooth (classic Server and Client) IsConnected does not report disconnected state? Android 8

the IsConnected property never was able to detect, that a connection is gone see also Change Text when Bluetooth disconnected as the bluetooth protocol was designed, there is no way to detect, if a connection still is alive, therefore you have to send regularly (i.e. poll) some data to the device. And if you get an error, then you know, that the connection was lost… see also A simple Bluetooth Chat with App Inventor 2 Taifun Trying to push the limits! Snippets, Tutorial…

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