57 lines
1.5 KiB
Markdown
57 lines
1.5 KiB
Markdown
# BLE
|
|
|
|
A modern, cross-platform Go library for Bluetooth Low Energy
|
|
|
|
This package is a working but incomplete interface for access to Bluetooth
|
|
Low Energy devices. It is intended to support multiple operating systems
|
|
with a uniform API. Currently, MacOS and Android are supported. Android
|
|
support requires the use of [Gio](https://gioui.org).
|
|
|
|
The API is asyncrhonous and event driven. To access Bluetooth hardware,
|
|
first create a `BLE` variable with `NewBLE()`. On Android, you must also
|
|
call `Enable` with a pointer to your Gio Window.
|
|
|
|
```go
|
|
import (
|
|
...
|
|
"git.wow.st/gmp/ble"
|
|
"gioui.org/app"
|
|
)
|
|
|
|
func runloop() {
|
|
b := ble.NewBle()
|
|
w := app.NewWindow()
|
|
b.Enable(w)
|
|
...
|
|
```
|
|
|
|
Once enabled, you can call the primary API functions, `Scan`, `StopScan`,
|
|
`Connect`, and `CancelConnection`. You can also query the state of the
|
|
Bluetooth hardware by calling `State`.
|
|
|
|
Calling `Events` on your `BLE` object returns a channel on which API events
|
|
are delivered. These events notify your program when the state of the
|
|
BLE hardware changes (e.g. powered on or off), peripherals are connected,
|
|
services or characteristics are discovered, or values for characteristics
|
|
are updated.
|
|
|
|
Using Gio, your main event loop will look something like this:
|
|
|
|
```
|
|
for {
|
|
select {
|
|
case e := <-b.Events():
|
|
switch e := e.(type) {
|
|
// Handle BLE Events
|
|
}
|
|
}
|
|
case e := <-w.Events():
|
|
switch e := e.(type) {
|
|
// Handle Gio events
|
|
}
|
|
}
|
|
}
|
|
```
|
|
|
|
An example heart rate monitor app can be found at [git.wow.st/gmp/hrm](https://git.wow.st/gmp/hrm).
|