It's been two days since the post is open and no one has found the answer to my question, and working hard on this topic I finally found the solution. So I decided to publish the complete solution, the installation of Grunt and then Livereload and how to configure both together because I found that they are very useful tools for Magento2 and even more for the frontend developers
###Let's start:
What is LiveReload ?
For those who don't know what is LiveReload, LiveReload monitors changes in the file system. As soon as you save a file, it is preprocessed as needed, and the browser is refreshed.
Even cooler, when you change a CSS file or an image, the browser is updated instantly without reloading the page.
I find this beautiful because for a developer Magento when it is in full development or integration he is obliged to refresh the page manually to see the result, then he goes back on his code he update, he saves, he clean the cache, then he returns to the browser , he refresh the browser and so on, while with the liveReload it's over all that, it is just enough to save the update and 'Hoop' magically the content that you have changed instantaneously appear without refreshing the browser and without cleaning the cache, deploying the static-content either but for the cache, you also need Grunt but I explain in detail how to put this.
What is Grunt ?
Grunt is a JavaScript Task Runner, a tool that allows you to create automated tasks in JavaScript,
it is very useful for Magento 2 because by its configuration, it allows us to removes the theme related static files in the pub/static and var directories, set up the .less files, and especially the watch that observes the changes of the files and which it is indispensable for the our liveReload
Now the installation :
###Grunt:
Important : be sure that you are in developper mode, in root project location when you execute the command bellow.
Rename the package.json.sample to package.json,
Gruntfile.js.sample to Gruntfile.js
We have to install npm node.js on your machine : sudo apt-get install npm
Install Grunt CLI : npm install -g grunt-cli
Refresh nodejs : npm install
To make sure that the npm is well installed the npm -v should output something like: 5.7.1, for Grunt grunt --version should output something like: grunt-cli v1.2.0
Grunt theme configuration: go to : dev/tools/grunt/configs/themes.js then add your current theme name that you are used, assuming that your theme name is : Prince/amir in : app/design/frontend/Prince/amir so you add the following in module.exportslike this:
module.exports = {
...
prince: { // for the clean command
area: 'frontend',
name: 'Prince/amir', //Vendor/theme
locale: 'fr_FR', //locale
files: [
'css/styles-m',
'css/styles-l',
'css/custom' // for custom.less for example
],
dsl: 'less'
...
},
You can use grunt clean:prince to removes the theme related static files in the pub/static and var directories.
Save
. More informations
###LiveReload:
npm install -g livereload
To make sure that the liveReload is well installed, livereload -v should output the version something like : 0.7.0
Install the LiveReload browser extension, available for Chrome and Firfox.
Add the script line bellow inside <head> tag in default.xml or default_head_blocks.xml of your current theme example : app/design/frontend/Prince/amir/Magento_Theme/layout/default_head_blocks.xml
<?xml version="1.0"?>
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="../../../../../vendor/magento/framework/Module/etc/module.xsd">
<head>
<script src="http://200.120.00.01:35729/livereload.js" src_type="url"></script>
</head>
Here as you see there is an IP(200.120.00.01) address plus the port(35729) plus livereload.js file
So what to do: replace this IP with your IP project, the port remains the same dont change it 35729 and the livereload.js you copy it in your root project, you can get it from the livereload installation(remember we installed it before) the path is: /usr/lib/node_modules/livereload/ext/livereload.js, or from this github.
###it's time to practice:
Run grunt clean, grunt less, grunt execute (sometimes magento doesn't work well with livereload if it has not been executed before) and then
We launch the Grunt watch to monitor our files changes.
Check if the LiveReload browser extension icon is well activated, in Firefox the icon comes green, in Chrome the small dot inside the circle becomes full black
important : if everything is good, if you enter in your browser your IP:35729 example : 200.120.00.01:35729, you'll see some welcome message like:
tinylr "Welcome"
version "0.2.1"
- Open your custom.css for example then change something then save, here you'll see in
grunt watch some new line appears tells that this file has been changed something like:
File "pub/static/frontend/Prince/amir/fr_FR/css/custom.css" changed.
and look now your browser, Hoop the item that you just changed appeared and updated instantly without reloading the page, also without cleaning the cache or deploying the static-content, everything is done automatically.
here I am finished, I hope you will enjoy this, it is really useful tool.
Good luck.
Best Answer
Ran into the same issue and in the end figured I've not had livereload node module installed (and yes I ran npm install like a few times) so installing livereload module through given below command fixed the issue: