Electron - Can my app communicate with the main and renderer processes?

Question

I have written a very, very basic electron application - The standard hello world type, where you basically have a HTML file which says "Hello, World" - and that lives in the "app" directory within electron, and then is loaded via main.js when you run the app.

Now, lets say I want to be able to maybe communicate with either of those processes (main, or renderer, preferably both!) from the javascript within my application, can that be done? I can't really find anything online about it - but my main problem might be that I don't really even know what to be searching for in the first place. I am very new to Electron.

Answer 1

I suppose you are talking about the main process and other browser windows.

You can use BrowserWindow.webContents.send(channel[, arg1][, arg2][, ...]) to send messages from the main process to to a browser window, and receive it using ipcRenderer. Take this example:

Main process:

subWindow.webContents.send("foo","bar");

The BrowserWindow called subWindow:

var ipc=require("electron").ipcRenderer;
ipc.on("foo",(event, arg1) => {
    console.log(arg1); //Outputs "bar"
});

When you want to send data from the browser window to the main process, use remote.app.emit. Receive it using app.on. The same example:

Main process:

var app=require("electron").app;
app.on("test",(arg) => {
    if (arg=="hey!") console.log("ha!");
}

subWindow:

require("electron").remote.app.emit("test","hey!");