Simple message passing between 'background.js' to 'contentScript.js'

Question

I\'m trying to apply the following flow :

binding for keys in the background.js , when pressing them : Sending message from background.js -> c

Answer 1

There are 3 ways to Send Message in Chrome Extension, you can refer to Message Passing.

Usually use one-time request, for example:

In background.js

chrome.tabs.query({active: true, currentWindow: true}, function(tabs) {  
  chrome.tabs.sendMessage(tabs[0].id, {message: "hello"}, function(response) {
    console.log(response);
  }); 
});

In contentscripts.js

chrome.runtime.onMessage.addListener(function(request, sender, sendResponse) {
  console.log(request.message);
  if (request.message == "hello") {
    sendResponse({farewell: "goodbye"});
  }
});