Tag: Drupal

Introduction to Paragraphs Drupal 8

Precious Tips For Paragraphs In Drupal 8 Web Services
Paragraphs is a contributed module which allows creation, administration, and display of customization content components.

In other words, Paragraphs gives you cleaner data structures so you can give more editing power to your end-users.

This module replaces drupal’s standard body field with paragraph types. This allows any type of content to be added on

the page including but not limited to HTML, images, videos etc. All these can be added by users. Users can add as many

paragraphs as they like all the while keeping them all responsive. Developers can reuse paragraphs and layouts.

Paragraphs are basic Drupal entities. This allows site builder control over fields used in paragraphs and their display.

This also makes content saved in paragraphs compatible with Search API, views, and services.

Below is the step by step instructions to work with Paragraphs module:

1 – Download and enable the module
Paragraphs module follows standard process to download and enable.  Module depends on entity reference revision.

You can download and enable this module via drush as well.

2 – Add paragraph types
Paragraphs do not come with any predefined paragraph types. Developers can add as many paragraph types they want by going to admin > structure > paragraphs

To add a paragraph, click on “Add paragraph”. Add fields


Add fields that you want in this paragraph. Go to manage form display and manage display to adjust field display.

3 – Add paragraph field in the content type

paragraph-field.png

Allow this field to have multiple values. Select which paragraphs you want available in this field on field settings and save.

4 – Add content

Add content. In paragraph field, you get a list of all the paragraphs you have created and are available for this field.

Add as many paragraphs as you need.

You can change the order as well.

5 – Theme your paragraphs

Paragraphs can be themed separately. You can use the same template everywhere this paragraph is used.

The file name needs to

“Paragraph–machine-name-of-your-paragraph.html.twig”

Summary

Paragraph provides various advantages to all users of the site. Site owners get content that is responsive and works on all platforms.

Content authors can choose on the fly between predefined paragraph types. They get more structured content creation process.

Developers have full control over fields to include and paragraphs and how they should look.

Stay tuned for more on paragraphs!

Hope this helped you to get most out of the system. Feel free to share your reviews or need assistance for

Drupal Website Migration then gets in touch with us. Pick the best answer for your requirements.

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Create Custom Multistep Form Using Ajax

Multistep Form Using Ajax
Don’t want long forms on your website? Convert it into multi-step form, as it is more convenient and provides step by

step procedure to follow by user. This blog will provide a way to create of multi step form using ajax.

https://goo.gl/P1BrVx 1. Create a menu item using hook_menu()

/** * Implementation of hook_menu(). */ function custom_menu() { $menu[‘multistep_form’] = array ( ‘title’ => ‘Multistep Form’, ‘description’ => ‘To create multistep form’, ‘page callback’ => ‘drupal_get_form’, ‘page arguments’ => array(‘ajax_multistep_form’), ‘access callback’ => TRUE, ); return $menu; }

  1. Define a callback functionIt includes stepwise fields. It contains fieldset for each step with their respective fields. Then It will includes buttons for each step.

We have called ajax_multistep_form_ajax_callback function it returns the entire form each time the function is called. Added a wrapper div “ajax_multistep_form’” to update the form using AJAX.

$form[‘buttons’][‘next’] = array ( ‘#type’ => ‘submit’, ‘#value’ => t(‘Next’), ‘#ajax’ => array ( ‘wrapper’ => ‘ajax_multistep_form’, ‘callback’ => ‘ajax_multistep_form_ajax_callback’, ), );

 

 

function ajax_multistep_form($form, &$form_state) {   // If $form_state[‘step’] is not set then set default to 1 $form_state[‘step’] = isset($form_state[‘step’]) ? $form_state[‘step’] : 1; // Add a wrapper div to update the form using AJAX $form[‘#prefix’] = ‘

‘; $form[‘#suffix’] = ‘

‘;   switch($form_state[‘step’]) { // Step 1 case 1: $fname_default_value = $lname_default_value = ”; if(isset($form_state[‘values’][‘step_1’])) { $fname_default_value = $form_state[‘values’][‘step_1’][‘fname’]; $lname_default_value = $form_state[‘values’][‘step_1’][‘lname’]; } elseif(isset($form_state[‘storage’][‘step_1’])) { $fname_default_value = $form_state[‘storage’][‘step_1’][‘fname’]; $lname_default_value = $form_state[‘storage’][‘step_1’][‘lname’]; }   $form[‘step_1’] = array( ‘#type’ => ‘fieldset’, ‘#title’ => t(”), ‘#collapsible’ => false, ‘#collapsed’ => false, ); $form[‘step_1’][‘fname’] = array( ‘#type’=>’textfield’, ‘#required’ => true, ‘#title’=>t(‘First Name’), ‘#default_value’ => $fname_default_value, ); $form[‘step_1’][‘lname’] = array( ‘#type’=>’textfield’, ‘#required’ => true, ‘#title’=>t(‘Last name’), ‘#default_value’ => $lname_default_value, ); break; // Step 2 case 2: $phone_default_value = ”; if(isset($form_state[‘values’][‘step_2’])) { $phone_default_value = $form_state[‘values’][‘step_2’][‘phone’]; } elseif(isset($form_state[‘storage’][‘step_2’])) { $phone_default_value = $form_state[‘storage’][‘step_2’][‘phone’]; }   $form[‘step_2’] = array( ‘#type’ => ‘fieldset’, ‘#title’ => t(”), ‘#collapsible’ => false, ‘#collapsed’ => false, ); $form[‘step_2’][‘phone’] = array( ‘#type’=>’textfield’, ‘#required’ => true, ‘#title’=>t(‘Phone Number’), ‘#default_value’ => $phone_default_value, ); break; // Step 3 case 3: $city_default_value = $city_default_value = ”; if(isset($form_state[‘values’][‘step_3’])) { $street_default_value = $form_state[‘values’][‘step_3’][‘street’]; $city_default_value = $form_state[‘values’][‘step_3’][‘city’]; } elseif(isset($form_state[‘storage’][‘step_3’])) { $street_default_value = $form_state[‘storage’][‘step_3’][‘street’]; $city_default_value = $form_state[‘storage’][‘step_3’][‘city’]; }   $form[‘step_3’] = array( ‘#type’ => ‘fieldset’, ‘#title’ => t(”), ‘#collapsible’ => false, ‘#collapsed’ => false, ); $form[‘step_3’][‘street’] = array( ‘#type’=>’textfield’, ‘#required’ => true, ‘#title’=>t(‘Street Address’), ‘#default_value’ => $street_default_value, );   $form[‘step_3’][‘city’] = array( ‘#type’=>’textfield’, ‘#required’ => true, ‘#title’=>t(‘City’), ‘#default_value’ => $city_default_value, );   }     // Form Buttons $form[‘buttons’] = array ( ‘#type’ => ‘container’, ); // If we are on step 1, we do not want a back button if($form_state[‘step’] !== 1) { $form[‘buttons’][‘back’] = array ( ‘#type’ => ‘submit’, ‘#value’ => t(‘Back’), ‘#limit_validation_errors’ => array(), ‘#submit’ => array(‘ajax_multistep_form_back_submit’), ‘#ajax’ => array ( ‘wrapper’ => ‘ajax_multistep_form’, ‘callback’ => ‘ajax_multistep_form_ajax_callback’, ), ); }   if($form_state[‘step’] !== 3) { $form[‘buttons’][‘next’] = array ( ‘#type’ => ‘submit’, ‘#value’ => t(‘Next’), ‘#ajax’ => array ( ‘wrapper’ => ‘ajax_multistep_form’, ‘callback’ => ‘ajax_multistep_form_ajax_callback’, ), ); } else { $form[‘buttons’][‘submit’] = array ( ‘#type’ => ‘submit’, ‘#value’ => t(‘Submit’), ‘#ajax’ => array ( ‘wrapper’ => ‘ajax_multistep_form’, ‘callback’ => ‘ajax_multistep_form_ajax_callback’, ), ); } return $form; }

  1. Add validation for your fieldsIt will add validation for phone number field in step 2. You can add validations for other steps too.

function ajax_multistep_form_validate($form, &$form_state) { switch($form_state[‘step’]) { case “2”: $contact_phone = $form_state[‘values’][‘phone’]; $contact_errror = ‘”‘.$contact_phone .'”‘ . ‘ is not a valid North American phone number. Please enter a valid ten-digit phone number with optional extension in this format 123 456 7891.’; if (!preg_match(‘/([0-9]{3}?\s?[0-9]{3}?\s?[0-9]{4})/’, $contact_phone)) { form_set_error(‘phone’, $contact_errror); } break; } }

  1. Final submit function

function ajax_multistep_form_submit($form, &$form_state) {   $step = $form_state[‘step’];   //$form_state[‘storage’][‘step_’ . $step] = $form_state[‘step’];   if($form_state[‘step’] == 1) { $form_state[‘storage’][‘step_’ . $step][‘fname’] = $form_state[‘values’][‘fname’]; $form_state[‘storage’][‘step_’ . $step][‘lname’] = $form_state[‘values’][‘lname’];   } if($form_state[‘step’] == 2) { $form_state[‘storage’][‘step_’ . $step][‘phone’] = $form_state[‘values’][‘phone’]; }   if(isset($form_state[‘values’][‘next’]) && $form_state[‘values’][‘op’] == $form_state[‘values’][‘next’]) { // Goto next step $form_state[‘step’]++; }   if(isset($form_state[‘values’][‘back’]) && $form_state[‘values’][‘op’] == $form_state[‘values’][‘back’]) { // Goto next step $form_state[‘step’]–; } // Check if it is last step elseif(isset($form_state[‘values’][‘submit’]) && $form_state[‘values’][‘op’] == $form_state[‘values’][‘submit’]) {   $form_state[‘storage’][‘step_’ . $step][‘street’] = $form_state[‘values’][‘street’]; $form_state[‘storage’][‘step_’ . $step][‘city’] = $form_state[‘values’][‘city’];   $items = array($form_state[‘storage’][‘step_1’][‘fname’], $form_state[‘storage’][‘step_1’][‘lname’], $form_state[‘storage’][‘step_2’][‘phone’], $form_state[‘storage’][‘step_3’][‘street’], $form_state[‘storage’][‘step_3’][‘city’]); drupal_set_message(t(‘You submitted the following values:!values’, array(‘!values’ => theme(‘item_list’, array(‘items’ => $items)))));   $form_state[‘step’] = 1; $form_state[‘storage’] = array(); } $form_state[‘rebuild’] = TRUE; }

  1. Ajax callback function for every buttons in our form

function ajax_multistep_form_ajax_callback($form, &$form_state) { return $form; }

This it just an example, you store all steps value in “$form_state[‘storage’]” and use it.

$step = $form_state[‘step’]; $form_state[‘storage’][‘step_’ . $step][‘values’] = $form_state[‘values’];

Hope this helped you to get most out of the system. Feel free to share your reviews or need assistance regarding our

CakePHP development services then get in touch with us. #WeDrupalEveryday. Pick the best answer for your requirements.

Features & Use Of Display Modes In Drupal 8

Display modes are one of the core functionalities of Drupal 8. They are easy to create and provides great flexibility in terms of theming at entity viewing and editing level. Display modes are available for content, comment, contact messages, custom blocks, taxonomy terms, users. They are also available to views adding more power to views.

Display modes are located at Admin -> Structure -> Display modes -> View mode.

Two types of display modes are available: “view modes” and “form modes.”  Both these are an example of configuration entities.

View modes allow site builder to request a field to be rendered in a certain way. For example, we can have an article that has doctors field has entity reference. An article full mode display, we can request few details of doctor to be displayed. We can create a new display mode (“Doctor details”) to do so. On Doctor’s full view, we can include a brief summary of articles associated with them.  (In detail: https://goo.gl/9J2oms)

To create View mode 

Navigate to Admin -> Structure -> Display modes -> View mode

  1. Click on “Add view mode” to add new view mode

  2. Created view mode is available on content types. Navigate to manage display of the content type and enable view mode.

    Manage display console test.png

Once enabled, this mode can be used on referenced field.

Once view modes are enabled, we can theme it as per requirements. To get template suggestions, you need to turn on debug property from services.yml.

You can find theme suggestion in inspect element.

Display modes can also be used based on conditions and we can switch mode based on conditions.

function hook_entity_view_mode_alter(&$view_mode, Drupal\Core\Entity\EntityInterface $entity, $context) {
  // For nodes, change the view mode when it is teaser.
  if ($entity->getEntityTypeId() == 'node' && $view_mode == 'teaser') {
    $view_mode = 'my_custom_view_mode';
  }
}
Hope this helped you to understand Display Modes in Drupal 8, Feel free to drop us a line for any Drupal 8 related work/queries/tasks, or Need any assistance regarding Drupal 8 Web design & Development.
Always ready to help 🙂

Everything You Need To Know About Drupal Mail System

Drupal Mail System

This blog is all about Drupal Mail system. Email sending in Drupal is entirely straightforward. Essentially you just need to manage two stages to send an email to somebody:

In Drupal to sends an email we need to take care of two things:

  • Declare all the required properties (subject, body, headers, etc) under hook_mail().
  • Call drupal_mail() with the argument for actually sending the email.

However, in the situation like greater and complex site, the above strides won’t be sufficient. In any case, Drupal gives us the Flexibility to redo email sending process, before that it’s important to know how stuff functions in the background first, with the help of Drupal you can easily generate custom pdf using the print module. In this blog, I’ll demonstrate to you how you can redo and extend the Drupal mail framework to satisfy your necessities.

The Email Sending Process

While sending an email drupal_mail() function uses system class for sending an email. Each mail framework needs to actualize MailSystemInterface class to define its own mail sending conduct.

MailsystemInterface class utilizes two strategies:

  • format()
  • mail()

The Mail System Module

Mail related settings can be set through Configuration > System > Mail System.

The mail system variable contains two things:

  • default-system => DefaultMailSystem
  • mailsystem_theme => current.

These key-value pairs are the settings you can adjust under the “Mail System Settings” fieldset.

DefaultMailSystem

The default-system email key describes which mail system class will be used by default for all outgoing emails.

If you don’t modify the site-wide mail system class then this one will be used by drupal_mail() by default.

The mailsystem_theme defines which theme will be used to render emails. Let’s say you are using Mime Mail which

uses a specific template file for it’s emails. The Mail System module checks every theme registry entry for a specific

“mail theme” key/property and if it exists in a particular entry then the specified mailsystem_theme value will be used

to search for more specific template files when the theme registry entry related theme hook will be called.

New Class

If you have two or more different mail system classes available in your system provided by different modules.

If you want to use any custom mail class which would use format() method of one mail system class and mail()

method from another class, so here you can use New Class which allows combining two different mail system classes.

New Setting

The Mail System module permits you to effortlessly add new email keys to the mail_system variable by choosing a

module and a particular email key from its hook_mail() execution.

 

Afterward added new email key to the mail_system variable you will ready to choose mail system class for it.

You will have the capacity to see it under all inclusive default MailSystemInterface class settings.

At the point when drupal_mail is called with your demo_custom _mail email key, then the in a roundabout way utilized

drupal_mail_system() function checks if this email_key exists in mail_system variable. It finds the related key then the

related mail system class will be utilized rather than default class.

Hope this helped you to get most out of the system. Feel free to share your reviews and need assistance regarding

Drupal Development Services. #WeDrupalEveryday

Pick the best answer for your requirements.

Tips To Upgrade Commerce Coupon Module In Drupal

Commerce Coupon Module

Commerce coupon module adds Commerce coupon facility to Drupal commerce.

Commerce coupon 7.x-2.x is recommended version. This version depends on Commerce Discount.

Commerce coupon 7.x-2.x has many architectural improvements and new features which include integration with commerce discount, multiple discounts per coupon, integration with inline conditions.

There are no fixed amount coupons or percentage coupons with this version. Instead, we use discounts and use them with coupons.

Upgrading from Commerce coupon 7.x-1.x to Commerce coupon 7.x-2.x is not directly supported. It is two step process.

As per module page on drupal.org, “Commerce Coupon 7.x-2.x-beta2 has an upgrade path from 1.x to 2.x. It works for upgrading relatively simple coupon 1.x sites; mileage may vary if you have a lot of custom coupon functionality though.”

So in order to upgrade to latest commerce coupon, we first need to upgrade to beta2 and then upgrade to latest version.

Below are the steps to upgrade normal commerce coupon setup without any additional customization.

  • First things first, take a backup.
  • Upgrade to Commerce coupon 7.x-2.x-beta3 following standard upgrade process. You will need to add commerce discounts and inline conditions modules installed before upgrading commerce coupon.
  • Once updates are run, you will see your old coupons converted into new coupon and discount systems. Discounts are created for previous fixed and percentage coupons.
  • Upgrade to latest commerce coupon version following standard upgrade process.
  • Make sure to give permission to required user roles to “Redeem coupon”.

This process assumes that there is no custom coupon functionality is added and no additional modules are used along-w

ith commerce coupon. The Success of upgrade process largely depends on how coupon module is used and customization is done on it.

Below are the steps to upgrade commerce coupon with Commerce Coupon by product reference module installed.

  • Take a backup.
  • Delete product reference fields from coupons.
  • Disable Commerce Coupon by product reference module.
  • Upgrade commerce coupon as outlined in steps 2,3 and 4 in upgrade normal commerce coupon.
  • Edit required discounts and add products.

This makes sure that this discount applies to specific products only.

  • Give appropriate user roles permission to “Redeem coupon”.

Since inline conditions are also installed, you can create coupons while creating discounts.

You can also consider adding Commerce discount Extra module which provides various common discount condition And offers types.

Need more assistance regarding Drupal Commerce Module Development Contact us now and Feel free to share your views/feedback for any further queries.

Sharing Insights For Drupal Mountain Camp Event

dc_davos
My Takeaways from the Drupal Mountain Camp Event, 16-19 February 2017, Davos, Switzerland.

~Climb mountains, not so that the world can see you but so you can see the world!~ And I was blessed to get the opportunity in the most beautiful place on earth! Imagine attending a Drupal Event in the scenic Swiss Alps (with temperatures plummeting to as low as minus 11)! The sights were no less than a fairy tale, and the Drupal learning – truly out of this world. No words can describe, no camera can ever capture the beauty of the place (and the learning from the event) – one has to live it, experience it and boy were I lucky!

The 4-day Drupal Mountain Camp Event was held at Davos – a valley in Eastern Switzerland and surrounded by snow-clad, picturesque mountains. My hotel was located at an altitude, with the very relatively low level of oxygen. The experience was truly exhilarating – almost like Drupal coding while hiking! The venue of the Mountain Camp Event is an International Congress Center, host to many International conferences. The 4-day event, held from 16-19 February 2017 was a perfect combination of coding and (winter) chill, events and entertainment, food and fun.

The first day began with a warm welcome of a delicious chocolate mountain – the Swiss are known for their chocolates, and the mountain was truly a finger-licking experience. While the days were spent in workshops and sprints – with extraordinary learning, evenings were fun-filled. On the Thursday evening, we got to try our hands at ice skating! Having only seen people skate in movies, it was a great chance for us to feel no less than movie stars! On the next evening, we got to enjoy an incredible sledge ride in the Alps – spinning down the slopes (at what feels like a million kilometers an hour) resulted in a great adrenaline rush. On Saturday night, we got to see a live ice hockey match between Davos and Zurich – thanks to the sponsors. And on Sunday, after a day spent in sprints, we could also ski and snowboard – god was I living a dream?

I was very lucky to have heard some great keynotes (especially on Open Source & API first Drupal), some eye-opening talks and sessions in the Drupal community, in addition to education, research, and Agile process tips for attendees of all levels (technical developers, business owners, and project managers).

With this event, I experienced my many firsts! My 1st time in Switzerland, my 1st time as a speaker, my 1st sledging adventure, the 1st time I witnessed snowfall, and my 1st Live Hockey match! I was also privileged to attend the Speaker Dinner (don’t forget to catch the pictures on Twitter and Flickr). The social nights were fab – I thoroughly enjoyed the Swiss beer, made some great new friends, and danced to some peppy Indian and Bollywood numbers.

I thought I was the farthest travelled attendee, all the way from India, while there was Lauri who came from across the world – Australia.  A memory: Signing on the Drupal Love board was fun, and it has been safely stashed by Ursin Cola.

All in all, a marvelous event! I would like to thank the organizers, sponsors, and speakers from the bottom of my heart, and also to those innumerable strangers who helped me find my way in a German speaking country, a place where English is not even an option!

AddWeb Solution

Guide To Customize Google Map Style And Custom Zoom Bar

custom-zoom

Google map theming and configuration with custom zoom controls, please follow the below details:

Styling google map allows us to change standard google map style and customize maps visual display like road, water, park and etc.

To make changes in standard google map style, we can use json array as per below:

var styledMapType = new google.maps.StyledMapType([
  { elementType: 'geometry', stylers: [{color: '#EBE5E2'}]},
  { elementType: 'labels.text.fill', stylers: [{color: '#520000'}]},
  { elementType: 'labels.text.stroke', stylers: [{color: '#F5E8DA'}]},
  {
    featureType: 'administrative',
    elementType: 'geometry.stroke',
    stylers: [{color: '#C9A193'}]
  },
  {
    featureType: 'administrative.land_parcel',
    elementType: 'geometry.stroke',
    stylers: [{color: '#DCD6B2'}]
  },
  {
    featureType: 'administrative.land_parcel',
    elementType: 'labels.text.fill',
    stylers: [{color: '#AEA5A0'}]
  },
  {
    featureType: 'landscape.natural',
    elementType: 'geometry',
    stylers: [{color: '#DFDFBB'}]
  },
  {
    featureType: 'poi',
    elementType: 'geometry',
    stylers: [{color: '#DFC47F'}]
  },
  {
    featureType: 'poi',
    elementType: 'labels.text.fill',
    stylers: [{color: '#93746E'}]
  },
  {
    featureType: 'poi.park',
    elementType: 'geometry.fill',
    stylers: [{color: '#9DB04A'}]
  },
  {
    featureType: 'poi.park',
    elementType: 'labels.text.fill',
    stylers: [{color: '#197515'}]
  },
  {
    featureType: 'road',
    elementType: 'geometry',
    stylers: [{color: '#F5E4BF'}]
  },
  {
    featureType: 'road.arterial',
    elementType: 'geometry',
    stylers: [{color: '#FDFBF3'}]
  },
  {
    featureType: 'road.highway',
    elementType: 'geometry',
    stylers: [{color: '#F8C452'}]
  },
  {
    featureType: 'road.highway',
    elementType: 'geometry.stroke',
    stylers: [{color: '#E9BF79'}]
  },
  {
    featureType: 'road.highway.controlled_access',
    elementType: 'geometry',
    stylers: [{color: '#E97741'}]
  },
  {
    featureType: 'road.highway.controlled_access',
    elementType: 'geometry.stroke',
    stylers: [{color: '#DBA37F'}]
  },
  {
    featureType: 'road.local',
    elementType: 'labels.text.fill',
    stylers: [{color: '#80544F'}]
  },
  {
    featureType: 'transit.line',
    elementType: 'geometry',
    stylers: [{color: '#DFCD95'}]
  },
  {
    featureType: 'transit.line',
    elementType: 'labels.text.fill',
    stylers: [{color: '#8F726D'}]
  },
  {
    featureType: 'transit.line',
    elementType: 'labels.text.stroke',
    stylers: [{color: '#EBD9B0'}]
  },
  {
    featureType: 'transit.station',
    elementType: 'geometry',
    stylers: [{color: '#DFD2A9'}]
  },
  {
    featureType: 'water',
    elementType: 'geometry.fill',
    stylers: [{color: '#BAD3C2'}]
  },
  {
    featureType: 'water',
    elementType: 'labels.text.fill',
    stylers: [{color: '#8E9985'}]
  }
]);

Below is the example of google style:

Before style applied

After style applying:

Google map provides ease level of customization.

We can make changes as per our need easily. I have provided an example to configure zoom, scroll, street view and etc options to change default google map.

// Create a map object, and include the MapTypeId to add
// to the map type control.
var map = new google.maps.Map(document.getElementById('gmap'), {
  center: {lat: 23.028349, lng: 72.559097},
  zoom: 11,
  mapTypeControlOptions: {
    mapTypeIds: ['roadmap', 'satellite', 'hybrid', 'terrain', 'styled_map'],
  },
  scrollwheel: true,
  mapTypeControl: true,
  mapTypeControlOptions: {
      style: google.maps.MapTypeControlStyle.HORIZONTAL_BAR,
      position: google.maps.ControlPosition.LEFT_TOP
  },
  zoomControl: false,
  // zoomControlOptions: {
  //     style: google.maps.ZoomControlStyle.LARGE,
  //     position: google.maps.ControlPosition.LEFT_TOP
  // },
  scaleControl: true,
  streetViewControl: true,
  streetViewControlOptions: {
      position: google.maps.ControlPosition.LEFT_TOP
  },
  fullscreenControl: false
});

To Add Custom zoom bar:

To add custom zoom bar on the map we can add custom element and use this element we can handle zoom controls.

I have added example code to add custom zoom controls.

// To customize google zoom bar to slider and search controlls
var centerControlDiv = document.createElement('div');
centerControlDiv.setAttribute("class", "gm-custom-controlls");
centerControlDiv.index = 1;

// Add custom zoom controlls
var centerControl = new ZoomControl(centerControlDiv, map, map.minZoom, map.maxZoom, map.zoom);

// map custom controlls to map
map.controls[google.maps.ControlPosition.BOTTOM].push(centerControlDiv);
// Zoom controlls
function ZoomControl(controlDiv, map, min, max, currentZoom) {

  var parentDiv = document.createElement('div');
  parentDiv.setAttribute("class", "gm-zoom-slider");

  var controlUI = document.createElement('input');
  controlUI.type = 'range';
  controlUI.value = currentZoom;
  controlUI.min = min;
  controlUI.max = max;
  controlUI.style.width = "400px";

  // Add zoom controlls
  var incControlls = document.createElement('div');
  incControlls.id = 'gm-zoom-inc';
  incControlls.innerHTML = '+';

  var decControlls = document.createElement('div');
  decControlls.id = 'gm-zoom-dec';
  decControlls.innerHTML = '-';

  parentDiv.appendChild(decControlls);
  parentDiv.appendChild(controlUI);
  parentDiv.appendChild(incControlls);

  controlDiv.appendChild(parentDiv);

  // Click event listner for side-bar
  controlUI.addEventListener('click', function() {
    map.setZoom(parseFloat(controlUI.value));
  });

  // Click event listner for inc button
  incControlls.addEventListener('click', function() {
    map.setZoom(parseFloat(controlUI.value) + 1 );
  });

  // Click event listner for dec button
  decControlls.addEventListener('click', function() {
    map.setZoom(parseFloat(controlUI.value) - 1 );
  });

  // Set slider value on zoom change 
  google.maps.event.addListener(map, 'zoom_changed', function(){
    controlUI.value = map.getZoom();
  });
}

Zoom bar will be displayed as per below screenshot:



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