Tauri Impl Multi Window

tauri-impl-multi-window

Quick Reference

Window Creation

Window Access

Inter-Window Communication

Critical Warnings

NEVER create two windows with the same label -- labels MUST be unique across the application. Duplicate labels cause a runtime error.

NEVER forget to await listen() before calling the unlisten function -- listen() returns Promise<UnlistenFn>, not UnlistenFn.

NEVER assume windows exist without checking -- ALWAYS use get_webview_window() and handle the None case.

ALWAYS clean up event listeners in component-based frameworks (React, Vue, Svelte) to prevent memory leaks.

ALWAYS use WebviewWindowBuilder (not WindowBuilder) for creating windows in Tauri 2 -- WindowBuilder is the v1 API.

ALWAYS use WebviewUrl::App() for local pages and WebviewUrl::External() for external URLs.

Essential Patterns

Pattern 1: Creating Windows from Rust

use tauri::webview::WebviewWindowBuilder;
use tauri::WebviewUrl;

// In setup() or any context with Manager access
.setup(|app| {
    let settings_window = WebviewWindowBuilder::new(
        app,
        "settings",                              // unique label
        WebviewUrl::App("settings.html".into()), // local page
    )
    .title("Settings")
    .inner_size(600.0, 400.0)
    .center()
    .resizable(true)
    .visible(false) // hidden by default
    .build()?;

    Ok(())
})

Pattern 2: Creating Windows from TypeScript

import { Window } from '@tauri-apps/api/window';

const settingsWindow = new Window('settings-window', {
    url: '/settings',
    title: 'Settings',
    width: 600,
    height: 400,
    center: true,
    decorations: true,
    resizable: true,
});

Pattern 3: Show/Hide Pattern

#[tauri::command]
fn show_settings(app: tauri::AppHandle) {
    if let Some(window) = app.get_webview_window("settings") {
        window.show().unwrap();
        window.set_focus().unwrap();
    }
}

#[tauri::command]
fn hide_settings(app: tauri::AppHandle) {
    if let Some(window) = app.get_webview_window("settings") {
        window.hide().unwrap();
    }
}

TypeScript equivalent:

import { Window } from '@tauri-apps/api/window';

async function toggleSettings() {
    const settings = await Window.getByLabel('settings');
    if (settings) {
        const visible = await settings.isVisible();
        if (visible) {
            await settings.hide();
        } else {
            await settings.show();
            await settings.setFocus();
        }
    }
}

Pattern 4: Inter-Window Communication via Events

Rust side -- emit to a specific window:

use tauri::Emitter;

#[tauri::command]
fn notify_settings(app: tauri::AppHandle, key: String, value: String) {
    app.emit_to("settings", "config-changed", serde_json::json!({
        "key": key,
        "value": value,
    })).unwrap();
}

TypeScript side -- send and receive between windows:

// In main window -- send to settings window
import { emitTo } from '@tauri-apps/api/event';

await emitTo('settings', 'config-changed', {
    key: 'theme',
    value: 'dark',
});

// In settings window -- listen for events
import { listen } from '@tauri-apps/api/event';

const unlisten = await listen<{ key: string; value: string }>('config-changed', (event) => {
    console.log(`Config changed: ${event.payload.key} = ${event.payload.value}`);
});

Pattern 5: Splashscreen Pattern

Show a splashscreen while the main window loads, then swap:

// tauri.conf.json -- define both windows
{
  "app": {
    "windows": [
      {
        "label": "splashscreen",
        "url": "/splashscreen",
        "width": 400,
        "height": 300,
        "decorations": false,
        "resizable": false,
        "center": true
      },
      {
        "label": "main",
        "url": "/index.html",
        "width": 1024,
        "height": 768,
        "visible": false
      }
    ]
  }
}

// src-tauri/src/lib.rs
#[tauri::command]
fn close_splashscreen(app: tauri::AppHandle) {
    if let Some(splash) = app.get_webview_window("splashscreen") {
        splash.close().unwrap();
    }
    if let Some(main) = app.get_webview_window("main") {
        main.show().unwrap();
        main.set_focus().unwrap();
    }
}

// In main window's initialization code
import { invoke } from '@tauri-apps/api/core';

document.addEventListener('DOMContentLoaded', async () => {
    // App is loaded, close splashscreen
    await invoke('close_splashscreen');
});

Pattern 6: Window Close Prevention

// Rust -- prevent close and hide instead
.on_window_event(|window, event| {
    if let tauri::WindowEvent::CloseRequested { api, .. } = event {
        if window.label() == "settings" {
            api.prevent_close();
            window.hide().unwrap();
        }
    }
})

// TypeScript -- confirm before closing
import { getCurrentWindow } from '@tauri-apps/api/window';

const win = getCurrentWindow();
await win.onCloseRequested(async (event) => {
    const confirmed = await confirm('Are you sure you want to close?');
    if (!confirmed) {
        event.preventDefault();
    }
});

Pattern 7: Window Event Handling

import { getCurrentWindow } from '@tauri-apps/api/window';

const win = getCurrentWindow();

// Resize events
await win.onResized(({ payload: size }) => {
    console.log(`Window resized to ${size.width}x${size.height}`);
});

// Focus events
await win.onFocusChanged(({ payload: focused }) => {
    console.log(`Window ${focused ? 'gained' : 'lost'} focus`);
});

// Theme change events (not supported on Linux)
await win.onThemeChanged(({ payload: theme }) => {
    console.log(`Theme changed to: ${theme}`);
});

WebviewWindowBuilder Methods

Window Geometry

.inner_size(width: f64, height: f64)    // Window content size
.min_inner_size(w: f64, h: f64)         // Minimum size
.max_inner_size(w: f64, h: f64)         // Maximum size
.position(x: f64, y: f64)              // Window position
.center()                               // Center on screen

Window Behavior

.title(title: impl Into<String>)        // Window title
.visible(bool)                          // Show on creation
.focused(bool)                          // Focus on creation
.maximized(bool)                        // Start maximized
.fullscreen(bool)                       // Start fullscreen
.resizable(bool)                        // Allow resizing
.closable(bool)                         // Allow closing
.minimizable(bool)                      // Allow minimizing
.maximizable(bool)                      // Allow maximizing
.transparent(bool)                      // Transparent background

Webview Configuration

.initialization_script(script: impl Into<String>)  // JS to run on page load
.user_agent(ua: &str)                               // Custom user agent
.devtools(enabled: bool)                             // Enable DevTools

Window Events (Rust)

Reference Links

• references/methods.md -- Complete API signatures for WebviewWindowBuilder, Window (TS), event functions
• references/examples.md -- Working code examples for multi-window patterns
• references/anti-patterns.md -- Common multi-window mistakes with explanations

Official Sources

• https://v2.tauri.app/develop/window-customization/
• https://docs.rs/tauri/latest/tauri/webview/struct.WebviewWindowBuilder.html
• https://v2.tauri.app/reference/javascript/api/namespaceevent/