Random color generator in javascript2 min read

If you ever tried to create HTML or SVG graphs, it is most likely that you have asked google the question How to generate random colors in javascript? , because I for sure did ???? .

Maybe you have searched it for some other reason. To create some cool UI or something, or maybe to irritate the user with stupid colors ???? .

If you have never searched it or thought about it, well why don’t you go ahead and try it now, it’s free after all.

There are plenty of resources in the internet that would help you get the job done. But here is my little experiment.

Where to start?

I want a function that would take the number of colors to generate, as input and outputs the generated colors.

Something like this –

//generate colors
function gen_colors(no_of_colors_to_generate) {

  //return an array of colors
  return colors;

So I decided to start with one color and tweak and shuffle the RGB values to generate random colors.

function color_gen(len) {
  //array in which generated
  //colors are stored
  colors = [];

  function gen_colors(colrs, len) {
    //generate the colors

  //start with rgb(180, 54, 54)
  return gen_colors([180, 54, 54], len);
 The full function
function color_gen(len) {
  //array in which generated
  //colors are stored
  colors = [];

  function gen_colors(colrs, len) {
    //loop and create all combinations
    //of the given color
    for (var i = 0; i < 3; i++) {
      for (var j = 0; j < 3; j++) {
        for (var k = 0; k < 3; k++) {
          var color_arr = [colrs[i], colrs[j], colrs[k]];
          //exclude if combination already exists
          //or have the same values ex rgb(180, 180, 180)
          if ((colors.indexOf(rgbize_arr(color_arr)) == -1) && !(colrs[i] == colrs[j] && colrs[i] == colrs[k])) {
          //if required colors
          //grater than 25 repeat the 
          //colors generated
          if (colors.length >= 25) {
            colors = colors.concat(colors);
          //if required no. of colors
          //are generated return
          if (colors.length == len) {
            return colors;
          //if generated > required
          //return only required
          else if (colors.length > len) {
            //console.log(colors.slice(0, len));
            return colors.slice(0, len);
          //if combinations are over
          //generate a new first color
          else {
            if (i == 2 && i == j && i == k) {
              var max_colr = Math.max.apply(Math, colrs);
              var min_colr = Math.min.apply(Math, colrs);
              var colr1 = Math.floor((max_colr + min_colr) / 4);
              var colr2 = Math.floor((max_colr + min_colr) / 2);
              var colr3 = Math.floor((max_colr + min_colr) / 3);
              return gen_colors([colr1, colr2, colr3], len);
  //convert array into rgb string
  function rgbize_arr(colr_arr) {
    return 'rgb(' + colr_arr.join() + ')';
  return gen_colors([180, 54, 54], len);


var new_colors = color_gen(25);

Gotta better technique (highly likely), comment below  ???? .

See the color generator in action-

See the Pen Javascript random color generation by hrishikesh mk (@avastava) on CodePen.0


Creating a Javascript load more plugin part 2 – Searching2 min read

In the first part Creating a Javascript load more plugin part 1 , we have created a javascript plugin which loads data from an API page. Let’s build upon on it.

Today we are going to add search option to our plugin, children ? .

Objectives ?

  • Add search bar to the page.
  • On input on search bar, load in relevant content from the API.
  • The API should take in a search parameter and provide relevant results.

As of now we are sending two parameters to the API – start and count. We would add one more q for sending the search query.

For learning how add searching option at the server end, please refer this tutorial from Codecourse – Basic PHP & MySQL Searching.

It uses PHP and MYSQL but you get the idea ? .

Demo page – Javascript load more plugin – search added.

We have to add one more line to our previous HTML code to include the search bar.

<input type="search" autocomplete="off" class="finder" />

We can add this anywhere inside our main container. Only condition is that it should have a class of finder, so that our plugin can identify it.

For styling HTML forms and form elements view this tutorial – Styling HTML Forms .

Updating the Plugin

Now let’s upgrade our plugin. First we would find the search bar.

//Search bar
this.finder = this.elem.getElementsByClassName('finder').length ? this.elem.getElementsByClassName('finder')[0] : false;

If you are not able to follow, please go through part one of this series.

Now, inside our lmore.load method we would append the search term to the GET query string.

//create query string with
//start and count variables
var qs = this.source + '?lmore_start=' + this.start + '&lmore_count=' + this.count;

//Send search query if search bar is available
qs += this.finder ? '&q=' + this.finder.value.trim() : '';'GET', qs);

Let’s add and event listener to the search bar so that, data can be loaded while searching.

We could load data on any event, but I prefer the on-input event because it gives an instant search effect.

I don’t like search bars that have a button which has to be clicked to search. We are in 2016, common guys ( who make me click a button to search ? )  ?.

We could even pass the event, as input for the plugin.

if (this.finder) {
  this.finder.addEventListener('input', function() {

You could also use this plugin to give search suggestions like google. Maybe we could use the plugin two times, one for suggestions and one for showing search results.

Comment below if you want to see this plugin give you search suggestions.


Javascript load more plugin6 min read

When searching the internet for a Javascript load more plugin, I came across a Jquery load more plugin tutorial in this youtube channel – Codecourse.

I highly recommend that the reader watch the Codecourse (formerly PHPacademy) tutorial and subscribe to their channel before continuing.

Link to the tutorial – Load More jQuery Plugin.

The tutorial was a really good and the plugin was very useful. But, with the aim of getting better at javascript and programming in general I tried to customize it.

So I decided to redo it in pure javascript. Here is how it went.

Demo link – Javascript load more plugin demo.

Please refer the above tutorial for creating a server side JSON API. The API would look like this Load more JSON API.

Now let’s get started with our plugin.

How to use?

<script src="lmore.js"</script>
  var itemload=new lmore({elem:cont,source:'json-api-load-more-plugin/',count:3});


  • elem: The main container.
  • source: JSON API page.
  • count: Number of results to load per request.


The plugin requires an HTML template to work with and the template would look like this.

<div id="cont">
  <span class="rescont" >
    <div id="ent_cont" class="items" >
      <div class="item" >
        <p data-field="id" class="hide" ></p>
        <h2 data-field="title" ></h2>
        <p data-field="description" ></p>
  <div id="no_result" class="nores" >No results to display.</div>
  <button id="load_more" class="load_more" >Load more</button>

Elements included are

  • #cont – Main Container.
  • .rescont – Container where results have to be loaded.
  • .items – Container for .item
  • .item – Individual data container which would be cloned with each result set.
  • [data-field] – The value of this attribute would be matched with the keys in the JSON object and corresponding values would be filled.
  • .nores – The element to be shown when there are no results. .rescont would be hidden and .nores would be shown if there are no results.
  • .load_more – Button which on click would load more results.


The plugin would take 3 inputs as given in the usage section.

It would have two main functions

  1. load – A function to load data from the JSON API page using ajax.
  2. append – A function to append the loaded data to the DOM.

The plugin

var lmore = function(options) {
  this.append = function() {

  this.load = function() {

Now we have to set the necessary properties.
//Default options
this.def_option = {
  elem: NaN,
  source: NaN,
  count: 3

//set the properties
if (options) {
  for (key in options) {
    if (this.def_option.hasOwnProperty(key)) {
      this[key] = options[key];

//Http request variable
this.http = 0;

//Starting point
this.start = 1;

//Load more button
this.load_more = false;

//Whether it load more button was clicked or not
this.is_load_more = false;
Getting load more button and saving it and it’s display property
  //set load more button
  if (this.elem.getElementsByClassName('load_more')[0]) {
    this.load_more = this.elem.getElementsByClassName('load_more')[0];
    this.load_more_display =; = 'none';
Cloning .item element and removing it from the DOM.
//Clone .item and remove it from DOM
this.items = this.elem.getElementsByClassName('items')[0];
this.itemo = this.items.getElementsByClassName('item')[0];
this.item = this.itemo.cloneNode(true);
this.nores = this.elem.getElementsByClassName('nores')[0];
this.rescont = this.elem.getElementsByClassName('rescont')[0];
this.resdis =;

//function to remove .item from DOM
this.remove = function() {
  while (this.items.firstChild) {
The load function
this.load = function() {
  //Check if load more button was clicked
  if (!this.is_load_more) {
    this.start = 1;
  } else {
    this.start += this.count;

  this.is_load_more = false;

  //Abort pending ajax calls if any
  if (this.http != 0) {

  //Ajax request
  this.http = new XMLHttpRequest();
  this.http.onreadystatechange = function() {
    if (this.http.readyState == 4 && this.http.status == 200) {
      res = JSON.parse(this.http.responseText);
      resp = res.items;

      //If last result hide load more button else show
      if (this.load_more) {
        if (!res.last) {
 = this.load_more_display;
        } else {
 = 'none';

      //Check if there are results
      //If not the no results text is shown
      if (undefined !== resp && resp != null && resp.length) {
        //Loop through each result set
        //and pass it to append function
        for (var i = 0, q = resp.length; i < q; i++) {
        } = 'none'; = this.resdis;
      } else { = 'block'; = 'none';
  //.bind is used so that 'this' is set
  //to lmore object

  //create query string with 
  //start and count variables
  var qs = this.source + '?lmore_start=' + this.start + '&lmore_count=' + this.count;'GET', qs);
The append function
//Append API data to DOM
this.append = function(value) {

  //Create a clone of the .item 
  var clone = this.item.cloneNode(true);

  //select all elements in .item
  //with data-field attribute
  var subs = clone.querySelectorAll('[data-field]');

  //loop through API result
  for (name in value) {
    if (value.hasOwnProperty(name)) {

      //loop through elements
      //with data-field attr
      for (var i = 0, q = subs.length; i < q; i++) {

        //id attr = key of object
        //set value
        if (subs[i].getAttribute('data-field') == name) {
          var ptext = value[name];
          var text = document.createTextNode(ptext);
          this.set_val(subs[i], ptext);

  //append the cloned element
  //to .items
Function to set value of any element
//Function to set value of any element
//params el - element to set value to
//val - the value to be set
this.set_val = function(el, val) {
  var node_type = el.nodeName.toLowerCase();
  if (node_type != 'input' && node_type != 'select' && node_type != 'textarea') {
    el.innerHTML = val;
    return true;
  if (node_type == 'select' || (node_type == 'input' && el.type != 'checkbox') || node_type == 'textarea') {
    if (el.hasAttribute('multiple')) {
      this.multi_set(el, val);
      return true;
    el.value = val;
    return true;
  } else if (el.type == 'checkbox') {
    el.checked = (val == '1') ? true : false;
    return true;
  return false;

//Function to set value of select multiple
this.multi_set = function(sel, values) {
  var vals = Array.isArray(values) ? values : String(values).split(',');
  var opt;
  for (var i = 0, len = sel.options.length; i < len; i++) {
    opt = sel.options[i];
    opt.selected = false;
    for (var x = 0, q = vals.length; x < q; x++) {
      if (opt.value == vals[x]) {
        opt.selected = true;
Initial loading

Also setting event listener on load more button to load data on click

//Load first set of data on page load

//The load more button on click would load
//the nextr set of results
if (this.load_more) {
  this.load_more.addEventListener('click', function() {

    //is_load_more is set to true
    //so that start is not reset
    this.is_load_more = true;

And finally the plugin is complete ????.

Download link – lmore.js.

Leave your suggestions below.