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NordicSemiconductor / Android-BLE-Library

A library that makes working with Bluetooth LE on Android a pleasure. Seriously.
BSD 3-Clause "New" or "Revised" License
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Handle BleServerManager #381

Closed pateychn closed 2 years ago

pateychn commented 2 years ago

Hello,

I'm implementing a BleServerManager for a client that needs to read a live computed value.

After reading the following PR : #143, and the library code, I see that onCharacteristicReadRequest is fully handled and returns the current characteristic value.

Is there a way to handle the readRequest and send a live computed value ? I looked at the waitForRead request but I think this is not what I want as the server queue is suspended until the characteristic is read.

philips77 commented 2 years ago

So what you can do, is use https://github.com/NordicSemiconductor/Android-BLE-Library/blob/42128bf3b0c6b571404992c81df44c21f33f89d2/ble/src/main/java/no/nordicsemi/android/ble/BleManager.java#L1112-L1128 whenever the characteristic value changes. This will set a new value to the characteristic, which can be read any time from a remote device. As you said, the onCharacteristicReadRequest is handled automatically, and will return the value set using the above method.

philips77 commented 2 years ago

Instead of returning the current value on read event, you set the value when it changes. The library returns the current value.

Remember, that you may have a shared characteristic (the same value for any connected device), or a dedicated characteristic (each connected device may read a different value). You define it when setting up the server.

pateychn commented 2 years ago

Thanks for your answer.

Indeed I'm using setCharacteristicValue, but in my case the client device executes a readCharacteristic to request the current time. So I understand that I should set the characteristic value every second. Could that have an impact on the operation queue (Maybe not while the client does not perform a read request ?) ?

sundaylol commented 2 years ago

Thanks for your answer.

Indeed I'm using setCharacteristicValue, but in my case the client device executes a readCharacteristic to request the current time. So I understand that I should set the characteristic value every second. Could that have an impact on the operation queue (Maybe not while the client does not perform a read request ?) ?

Did you find a solution? I also encountered this problem

philips77 commented 2 years ago

Please, follow #385. We will add a callback to send read response in some future release. You may also contribute and try creating a PR!

philips77 commented 1 year ago

Hello, I've now completed the task. Could you please give it a try? I will release 2.6.0-alpha02 shortly.