# Devices List

**Usage:** `"template": "list_devices"`

<figure><img src="https://998911913-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-MPk9cn4V7WnnKt7fbry%2Fuploads%2Fgit-blob-2f772da7c42082a8debc618de010ccdc2aceb835%2Flist-devices.png?alt=media" alt=""><figcaption></figcaption></figure>

{% code title="/drivers/\<driver\_id>/driver.compose.json" %}

```javascript
{
  "name": { "en": "My Driver" },
  "images": {
    "small": "/drivers/my_driver/assets/images/small.png",
    "large": "/drivers/my_driver/assets/images/large.png"
  },
  "pair": [
    {
      "id": "list_devices",
      "template": "list_devices",
      "navigation": { "next": "add_devices" },
      "options": { "singular": true }
    },
    {
      "id": "add_devices",
      "template": "add_devices"
    }
  ]
}
```

{% endcode %}

## **Options**

| Key        | Type      | Default | Description                               |
| ---------- | --------- | ------- | ----------------------------------------- |
| `singular` | `boolean` | `false` | Only allow a single device to be selected |

{% tabs %}
{% tab title="JavaScript" %}
{% code title="/drivers/\<driver\_id>/driver.js" %}

```javascript
const Homey = require("homey");
const DeviceApi = require("device-api");

class Driver extends Homey.Driver {
  async onPair(session) {
    session.setHandler("list_devices", async function () {
      const devices = await DeviceApi.discoverDevices();
      
      // you can emit when devices are still being searched
      // session.emit("list_devices", devices);

      // return devices when searching is done
      return devices;

      // when no devices are found, return an empty array
      // return [];

      // or throw an Error to show that instead
      // throw new Error('Something bad has occured!');
    });
  }
}

module.exports = Driver;
```

{% endcode %}

Because the `list_devices` template is very common the [`Driver#onPairListDevices()`](https://apps-sdk-v3.developer.homey.app/Driver.html#onPairListDevices) method exists which you can implement instead of the [`Driver#onPair()`](https://apps-sdk-v3.developer.homey.app/Driver.html#onPair) method.
{% endtab %}

{% tab title="TypeScript" %}
{% code title="/drivers/\<driver\_id>/driver.mts" %}

```mts
import Homey from "homey";
import DeviceApi from "./device-api.mjs";

export default class Driver extends Homey.Driver {
  async onPair(session: Homey.Driver.PairSession): Promise<void> {
    session.setHandler("list_devices", async (): Promise<object[]> => {
      const devices = await DeviceApi.discoverDevices();

      // you can emit when devices are still being searched
      // session.emit("list_devices", devices);

      // return devices when searching is done
      return devices;

      // when no devices are found, return an empty array
      // return [];

      // or throw an Error to show that instead
      // throw new Error('Something bad has occurred!');
    });
  }
}

```

{% endcode %}

Because the `list_devices` template is very common the [`Driver#onPairListDevices()`](https://apps-sdk-v3.developer.homey.app/Driver.html#onPairListDevices) method exists which you can implement instead of the [`Driver#onPair()`](https://apps-sdk-v3.developer.homey.app/Driver.html#onPair) method.
{% endtab %}

{% tab title="Python" %}
{% code title="/drivers/\<driver\_id>/driver.py" %}

```python
from device_api import DeviceApi
from homey import driver
from homey.pair_session import PairSession


class Driver(driver.Driver):
    async def on_pair(self, session: PairSession) -> None:
        async def on_list_device():
            devices = await DeviceApi.discover_devices()

            # you can emit when devices are still being searched
            # session.emit("list_devices", devices);

            # return devices when searching is done
            return devices

            # when no devices are found, return an empty list
            # return []

            # or throw an Error to show that instead
            # raise Exception("Something bad has occurred!")

        session.set_handler("list_devices", on_list_device)


homey_export = Driver

```

{% endcode %}

Because the `list_devices` template is very common the [`Driver#on_pair_list_devices()`](https://python-apps-sdk-v3.developer.homey.app/driver.html#homey.driver.Driver.on_pair_list_devices) method exists which you can implement instead of the [`Driver#on_pair()`](https://python-apps-sdk-v3.developer.homey.app/driver.html#homey.driver.Driver.on_pair) method.
{% endtab %}
{% endtabs %}


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://apps.developer.homey.app/the-basics/devices/pairing/system-views/devices-list.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.