Keep getting Error 515: Not connected to a Bluetooth Device

I've made an app that receives information from a HC-05 Bluetooth module connected through Arduino. I've made a List Picker to choose my HC-05, but I keep getting Error 515: Not connected to a Bluetooth Device even though it is paired when I check Bluetooth settings in my phone. Here's the code:

Why isn't this working? Thanks in advance.

The error isn't appearing anymore but none of my Bluetooth devices appear in the list, just a black screen. What am I doing wrong?

Give your app permission to scan for BlueTooth devices?

I already did that

You might want to show us the corresponding blocks...

Taifun


(Canned Response ABG - Bluetooth non-BLE SCAN Permission Blocks)

The easiest solution, for immediate relief
(from @Barry_Meaker) ...

I had the same issue. The problem is your app does not have permission to see nearby devices. The solution is to give your app permission on your phone (no code changes in your app).

on your phone,

  • goto settings
  • search for your app
  • in App Info for your app select Permissions
  • change Nearby Devices from Not Allowed to Allowed
  • Done

By the way, the very first time you run the app, Android will ask if you want to grant the app this permission. If you say no, or ignore the pop-up, the permission will be set as Denied. Android will not ask again.

A more complex approach, for professional app development:

See Bluetooth liste of devices deosn't work anymore - #7 by Anke
Special note for Xiaomi devices:
I have an error with bluetooth on android 12, Xiaomi Poco X3 NFC - #20 by Patryk_F