Error 515: Not connected to a Bluetooth device

I have built the program as described in the YouTube article The HC05 connected to the Arduino Uno is paired the Samsung smartphone.

When the slider in the app is moved an error appears "Error 515: Not connected to a Bluetooth device". The first ListPicker1 block calls and connects BluetoothClient1 . Text1 reads "not connected" in red.
I am a Bluetooth newbie. Can you help me???
Thanks in advance.

Please download and post each of those event block(s)/procedures here ...
(sample video)

I'm sorry to say, that as a bluetooth and AppInventor
newbie, I didn't understand the solution you provided.
I changed out the HC05 and left it un-powered while I reloaded the Arduino code but it made no difference.

What solution?

I posted a video to show you how to download your blocks and post them to this board.
The sample blocks I used were from a long time ago, for a different poster, and saved for people who don't know how to download blocks and how to post them to this board.

Those old blocks were not a solution to your specific problem.

Post your code and your blocks.

Thanks, I'll try to download my blocks.

I have three blocks in 3 png files in my Download directory. How do I upload the .png files so they are useful to you?

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This means that the problem code is probably in the event that responds to the slider moving.
Could you upload that event block here?

btw your clock example blocks from the screenshot will not help you to find out, if there still is a connection...

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…

also this

does not make any sense... just set Label1.Text to "Is connected" there


Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by Taifun.

@eugenejasper968 add an if condition like this

if BluetoothClient.IsConnected
then Send1ByteNumber...


Is this what you had in mind....

yes, exactly