Adding functionality to nRF Connect Desktop Bluetooth Low Energy App

[ThienVu]

Hello,

Currently I would like to add a functionality to Bluetooth Low Energy App (BLE). I have a bluetooth slave device that require a specific sequence of sending string and receiving notification string to setup. I use a nRF52840 USB Dongle as an adapter to connect to those slave devices.

I would like to add a button/option to the red area above to automate the configuration sequence. This includes sending a byte to specific service, receive notification from specific service. Where should I start? The examples on the nRF Connect Desktop app development page didn't help, and the documentation is not enough.

Thank you.

[Bence]

In your code onPairDevice is a property of ConnectedDevice which must be a function, but you did not provide a function but rather the return value of a function (writeCharacteristic). Try this way:

// onPairDevice={writeCharacteristic('1234', 0x22)}
onPairDevice={() => { writeCharacteristic('1234', 0x22); }}

[ThienVu]

Hi. 

Thank you for helping. 

I tried that, but it didn't work. The value on the '1234' characteristic of the advertising device didn't change. I think I need to call this function a very specific way.

Have anyone modified this app? Any help?

[Joakim Jakobsen]

Some feedback from our developers:

The correct way to implement the function is to 

1. Write the function, like calling deviceDetailActions and put it in a file in lib/actions
2. Create a container under lib/containers which pass the function to the component
3. Import the function into the component and use it

So it is using React and Redux framework. And in redux you use dispatch() to trigger the actions and change the states. So furthermore, if you need to manage the states, you have to create a file under reducers to manage the state and put it in container so that component can update it whenever the state has been updated.

Br,
Joakim

[ThienVu]

Thank you.

I looked at the writeCharacteristic function and noticed that it already have dispatch() in there, so I'm thinking it is called just like a regular function when needed, and it will dispatch the appropriate action accordingly. I think my problem is maybe I'm using the wrong function to do what I want.

Sorry for asking many questions. There isn't much documentation for nrf connect apps that I can find.

[ThienVu]

Thanks everyone.

I looked at the writeCharacteristic function and noticed that it already have dispatch() in there, so I'm thinking it is called just like a regular function when needed, and it will dispatch the appropriate action accordingly. I think my problem is maybe I'm using the wrong function to do what I want.

And regarding states and reducers, for this app, what do I need to keep track of in the state?

Sorry for asking many questions. There isn't much documentation for nrf connect apps that I can find.

This is the writeCharacteristic I'm talking about, located in deviceDetailsActions.js

export function writeCharacteristic(characteristic, value) {
    return (dispatch, getState) => (
        new Promise((resolve, reject) => {
            const adapterToUse = getState().app.adapter.bleDriver.adapter;

            if (adapterToUse === null) {
                reject(new Error('No adapter selected'));
                return;
            }

            const ack = !characteristic.properties.writeWoResp;

            adapterToUse.writeCharacteristicValue(characteristic.instanceId, value, ack, error => {
                if (error) {
                    dispatch(completedWritingAttributeAction(characteristic, null, error));
                    reject(new Error(error.message));
                    return;
                }
                dispatch(completedWritingAttributeAction(characteristic, value));
                resolve();
            });
        }).catch(error => {
            dispatch(showErrorDialog(error));
        })
    );
}