add preload.js script to electron main

src/background.ts

@@ -0,0 +1,92 @@
+"use strict";
+
+import { app, protocol, BrowserWindow } from "electron";
+import { createProtocol } from "vue-cli-plugin-electron-builder/lib";
+import installExtension, { VUEJS_DEVTOOLS } from "electron-devtools-installer";
+const isDevelopment = process.env.NODE_ENV !== "production";
+import * as path from "path";
+
+// Keep a global reference of the window object, if you don't, the window will
+// be closed automatically when the JavaScript object is garbage collected.
+let win: BrowserWindow | null;
+
+// Scheme must be registered before the app is ready
+protocol.registerSchemesAsPrivileged([
+  { scheme: "app", privileges: { secure: true, standard: true } }
+]);
+
+function createWindow() {
+  // Create the browser window.
+  win = new BrowserWindow({
+    width: 800,
+    height: 600,
+    webPreferences: {
+      // Use pluginOptions.nodeIntegration, leave this alone
+      // See nklayman.github.io/vue-cli-plugin-electron-builder/guide/security.html#node-integration for more info
+      nodeIntegration: (process.env
+        .ELECTRON_NODE_INTEGRATION as unknown) as boolean,
+      preload: path.join(__dirname, "preload.js")
+    }
+  });
+
+  if (process.env.WEBPACK_DEV_SERVER_URL) {
+    // Load the url of the dev server if in development mode
+    win.loadURL(process.env.WEBPACK_DEV_SERVER_URL as string);
+    if (!process.env.IS_TEST) win.webContents.openDevTools();
+  } else {
+    createProtocol("app");
+    // Load the index.html when not in development
+    win.loadURL("app://./index.html");
+  }
+
+  win.on("closed", () => {
+    win = null;
+  });
+}
+
+// Quit when all windows are closed.
+app.on("window-all-closed", () => {
+  // On macOS it is common for applications and their menu bar
+  // to stay active until the user quits explicitly with Cmd + Q
+  if (process.platform !== "darwin") {
+    app.quit();
+  }
+});
+
+app.on("activate", () => {
+  // On macOS it's common to re-create a window in the app when the
+  // dock icon is clicked and there are no other windows open.
+  if (win === null) {
+    createWindow();
+  }
+});
+
+// This method will be called when Electron has finished
+// initialization and is ready to create browser windows.
+// Some APIs can only be used after this event occurs.
+app.on("ready", async () => {
+  if (isDevelopment && !process.env.IS_TEST) {
+    // Install Vue Devtools
+    try {
+      await installExtension(VUEJS_DEVTOOLS);
+    } catch (e) {
+      console.error("Vue Devtools failed to install:", e.toString());
+    }
+  }
+  createWindow();
+});
+
+// Exit cleanly on request from parent process in development mode.
+if (isDevelopment) {
+  if (process.platform === "win32") {
+    process.on("message", data => {
+      if (data === "graceful-exit") {
+        app.quit();
+      }
+    });
+  } else {
+    process.on("SIGTERM", () => {
+      app.quit();
+    });
+  }
+}

src/preload.ts

@@ -0,0 +1,27 @@
+// All of the Node.js APIs are available in the preload process.
+// It has the same sandbox as a Chrome extension.
+import ipcRenderer from "electron";
+
+process.once("loaded", () => {
+  window.addEventListener("message", event => {
+    // do something with custom event
+    const message = event.data;
+
+    if (message.myTypeField === "handle-audio-stream") {
+      ipcRenderer.send("audio-stream", message);
+    }
+  });
+});
+
+window.addEventListener("DOMContentLoaded", () => {
+  const replaceText = (selector: string, text: string) => {
+    const element = document.getElementById(selector);
+    if (element) {
+      element.innerText = text;
+    }
+  };
+
+  for (const type of ["chrome", "node", "electron"]) {
+    replaceText(`${type}-version`, (process.versions as any)[type]);
+  }
+});