mirror of
https://github.com/tauri-apps/tauri.git
synced 2024-12-20 09:11:55 +03:00
134 lines
4.4 KiB
Markdown
134 lines
4.4 KiB
Markdown
---
|
|
title: Events
|
|
---
|
|
|
|
The Tauri event system is a multi-producer multi-consumer communication primitive that allows message passing between the frontend and the backend.
|
|
It is analogous to the command system, but payload type check must be written on the event handler and it simplifies communication from the backend to the frontend, working like a channel.
|
|
|
|
A Tauri application can listen and emit to global and window-specific events. Usage from the frontend and the backend are described below.
|
|
|
|
## Frontend
|
|
|
|
The event system is accessible on the frontend on the `event` and `window` modules of the `@tauri-apps/api` package.
|
|
|
|
### Global events
|
|
|
|
To use the global event channel, import the `event` module and use the `emit` and `listen` functions:
|
|
|
|
```ts
|
|
import { emit, listen } from '@tauri-apps/api/event'
|
|
|
|
// listen to the `click` event and get a function to remove the event listener
|
|
// there's also a `once` function that subscribes to an event and automatically unsubscribes the listener on the first event
|
|
const unlisten = await listen('click', event => {
|
|
// event.event is the event name (useful if you want to use a single callback fn for multiple event types)
|
|
// event.payload is the payload object
|
|
})
|
|
|
|
// emits the `click` event with the object payload
|
|
emit('click', {
|
|
theMessage: 'Tauri is awesome!'
|
|
})
|
|
```
|
|
|
|
### Window-specific events
|
|
|
|
Window-specific events are exposed on the `window` module.
|
|
|
|
```ts
|
|
import { getCurrent, WebviewWindow } from '@tauri-apps/api/window'
|
|
|
|
// emit an event that are only visible to the current window
|
|
const current = getCurrent()
|
|
current.emit('event', { message: 'Tauri is awesome!' })
|
|
|
|
// create a new webview window and emit an event only to that window
|
|
const webview = new WebviewWindow('window')
|
|
webview.emit('event')
|
|
|
|
```
|
|
|
|
## Backend
|
|
|
|
On the backend, the global event channel is exposed on the `App` struct, and window-specific events can be emitted using the `Window` trait.
|
|
|
|
### Global events
|
|
|
|
```rust
|
|
use tauri::Manager;
|
|
|
|
// the payload type must implement `Serialize`.
|
|
// for global events, it also must implement `Clone`.
|
|
#[derive(Clone, serde::Serialize)]
|
|
struct Payload {
|
|
message: String,
|
|
}
|
|
|
|
fn main() {
|
|
tauri::Builder::default()
|
|
.setup(|app| {
|
|
// listen to the `event-name` (emitted on any window)
|
|
let id = app.listen_global("event-name", |event| {
|
|
println!("got event-name with payload {:?}", event.payload());
|
|
});
|
|
// unlisten to the event using the `id` returned on the `listen_global` function
|
|
// an `once_global` API is also exposed on the `App` struct
|
|
app.unlisten(id);
|
|
|
|
// emit the `event-name` event to all webview windows on the frontend
|
|
app.emit_all("event-name", Payload { message: "Tauri is awesome!".into() }).unwrap();
|
|
Ok(())
|
|
})
|
|
.run(tauri::generate_context!())
|
|
.expect("failed to run app");
|
|
}
|
|
```
|
|
|
|
### Window-specific events
|
|
|
|
To use the window-specific event channel, a `Window` object can be obtained on a command handler or with the `get_window` function:
|
|
|
|
```rust
|
|
use tauri::{Manager, Window};
|
|
|
|
// the payload type must implement `Serialize`.
|
|
#[derive(serde::Serialize)]
|
|
struct Payload {
|
|
message: String,
|
|
}
|
|
|
|
// init a background process on the command, and emit periodic events only to the window that used the command
|
|
#[tauri::command]
|
|
fn init_process(window: Window) {
|
|
std::thread::spawn(move || {
|
|
loop {
|
|
window.emit("event-name", Payload { message: "Tauri is awesome!".into() }).unwrap();
|
|
}
|
|
});
|
|
}
|
|
|
|
fn main() {
|
|
tauri::Builder::default()
|
|
.setup(|app| {
|
|
// `main` here is the window label; it is defined on the window creation or under `tauri.conf.json`
|
|
// the default value is `main`. note that it must be unique
|
|
let main_window = app.get_window("main").unwrap();
|
|
|
|
// listen to the `event-name` (emitted on the `main` window)
|
|
let id = main_window.listen("event-name", |event| {
|
|
println!("got window event-name with payload {:?}", event.payload());
|
|
});
|
|
// unlisten to the event using the `id` returned on the `listen` function
|
|
// an `once` API is also exposed on the `Window` struct
|
|
main_window.unlisten(id);
|
|
|
|
// emit the `event-name` event to the `main` window
|
|
main_window.emit("event-name", Payload { message: "Tauri is awesome!".into() }).unwrap();
|
|
Ok(())
|
|
})
|
|
.invoke_handler(tauri::generate_handler![init_process])
|
|
.run(tauri::generate_context!())
|
|
.expect("failed to run app");
|
|
}
|
|
```
|