MarkupSrcSet

[tpr]

This is a very beta version of the separate functions I use to generate srcset/bgset markups. There's some similar functions floating around in the forum but this one is a bit different because you can set "named image sets" which you can use easily site-wide.

It's definitely work-in-progress so use it at your own risk.

MarkupSrcSet

Generate srcset and bgset markup for lazysizes.

Features

• generate srcset/bgset markup for lazysizes
• set image sizes in JSON array
• add required JavaScripts automatically (optional)
• fallback to smallest image size if JavaScript is not available

Usage

Image sets JSON (in module settings):

{
    "hero": [
        [640, 210], [1080, null], [1920, null]
    ],
    "featured-image": [
        [360, 240], 1.333, 2.667
    ],
    "gallery-thumb": [
        [240, 120], [480, 300], [800, 576]
    ]
}

Image methods

$image->srcset():

<img <?php echo $page->featured_image->srcset('featured-image'); ?>>

$image->bgset():

<div <?php echo $page->images->first()->bgset('hero'); ?>>Lorem ipsum</div>

https://github.com/rolandtoth/MarkupSrcSet

[tpr]

There are some pending updates to this, plus I guess I can't help myself to create an image method for rendering the markup instead of the global functions (eg. $img->srcset()).

[LostKobrakai]

$this->addHook("Pageimage::srcset", $this, "mySrcsetFunction"); 

The image is $event->object in the hook function. From this you could simply call your current global functions if you like.

[horst]

In addition to LostKobrakai, the function schema looks like:

public function mySrcsetFunction($event) {
    $image = $event->object;
        
        $markup = "<img src='{$lqip}' data-src='{$image->url}' {$aspectratio} class='lazyload lazypreload' alt='{$image->description}' />";

    $event->return = $markup;
}

[tpr]

v002 is up on GitHub:

https://github.com/rolandtoth/MarkupSrcSet

[jploch]

Hi!
This is probably a noob question (Iam a designer and frontend guy, just learned some basic php) :

I have several functions in a _function.php that I include in my templates.
How can I use this within a function in that file? I guess I have to redefine the variables, because they are not available there, but Iam not sure how to do this.

Here is an example (not working):

// album list function ----------------------
function albumList(){
 
	// Get the list of albums 
	$albums = wire("pages")->find("parent=/work/, template=project, limit=100, sort=sort");
 
	$out =" ";
 
	//Loop through the pages
	foreach($albums as $album){
		$out .="<a href='{$album->url}' class='item {$album->thumbnail->tags} {$album->thumbnail->orientation}'>";
		if($album->images){
			$out .="<img {$album->thumbnail->srcset('thumbnail', 'lazyload my-class inline-block', array('quality' => 80))} alt='{$album->thumbnail->Alt}'>";
		}
		$out .="<div class='item-info'><h3>{$album->title}</h3><h4>{$album->thumbnail->tags}</h4></div>";
		$out .="</a>";
 
	}

So how is the syntax for this?:

<img <?php echo $page->featured_image->srcset('featured-image', 'lazyload my-class inline-block', array('quality' => 80)); ?>>

Iam using PW 3.0.25
Thanks! this module looks very promising!

[tpr]

What variables are you missing? The function seems OK to me. Do you have a return $out at the end? Or do you have an error when running this?

[jploch]

I forgot to copy the out, but its there. here is the complete code:

/ album list function ----------------------
function albumList(){
 
    // Get the list of albums 
    $albums = wire("pages")->find("parent=/work/, template=project, limit=100, sort=sort");
 
    $out =" ";
 
    //Loop through the pages
    foreach($albums as $album){
        $out .="<a href='{$album->url}' class='item {$album->thumbnail->tags} {$album->thumbnail->orientation}'>";
        if($album->images){
            $out .="<img {$album->thumbnail->srcset('thumbnail', 'lazyload my-class inline-block', array('quality' => 80))} alt='{$album->thumbnail->Alt}'>";
        }
        $out .="<div class='item-info'><h3>{$album->title}</h3><h4>{$album->thumbnail->tags}</h4></div>";
        $out .="</a>";
 
    }
 
    echo $out;
}

I get the error:

Error: Call to a member function srcset() on null (line 14 of /homepages/11/d86659974/htdocs/website_susannerudolf/site/templates/_func.php) 

Line 14 is this:
 

$out .="<img {$album->thumbnail->srcset('thumbnail', 'lazyload my-class inline-block', array('quality' => 80))}

 

[jploch]

Iam using PW 3.0.25. Maybe thats the problem?

[tpr]

No, your $album->thumbnail seems NOT to be an image object.  Is thumbnail a valid field? if so, if it's set to hold multiple images, try $album->thumbnail->first()->srcset...

[tpr]

Plus you check for $album->images and then use $album->thumbnail, so one if them may be invalid. You may also check for $album->images->count() if there can be more than one image in the field (and the field name may be "thumbnail").

[jploch]

it holds multiple images. I tryed using first().

Now I get this:
Error: Exception: Method Pageimage::first does not exist or is not callable in this context (in /homepages/11/d86659974/htdocs/website_susannerudolf/wire/core/Wire.php line 409) #0 [internal function]: ProcessWire\Wire->___callUnknown('first', Array) #1 /homepages/11/d86659974/htdocs/website_susannerudolf/wire/core/Wire.php(347): call_user_func_array(Array, Array) #2 /homepages/11/d86659974/htdocs/website_susannerudolf/wire/core/WireHooks.php(548): ProcessWire\Wire->_callMethod('___callUnknown', Array) #3 /homepages/11/d86659974/htdocs/website_susannerudolf/wire/core/Wire.php(370): ProcessWire\WireHooks->runHooks(Object(ProcessWire\Pageimage), 'callUnknown', Array) #4 /homepages/11/d86659974/htdocs/website_susannerudolf/wire/core/Wire.php(371): ProcessWire\Wire->__call('callUnknown', Array) #5 /homepages/11/d86659974/htdocs/website_susannerudolf/wire/core/Wire.php(371): ProcessWire\Pageimage->callUnknown('first', Array) #6 /homepages/11/d86659974/htdocs/website_susannerudolf/site/temp This error message was shown because: you are logged in as a Superuser. Error has been logged.

sorry my bad, it was a long day, its just an image field with a single image. And it works when I use it without the module syntax like:

// album list function ----------------------
function albumList(){
 
    // Get the list of albums 
    $albums = wire("pages")->find("parent=/work/, template=project, limit=100, sort=sort");
 
    $out =" ";
 
    //Loop through the pages
    foreach($albums as $album){
        $out .="<a href='{$album->url}' class='item {$album->thumbnail->tags} {$album->thumbnail->orientation}'>";
        if($album->images){
            $out .="<img src='{$album->thumbnail->url}' alt='{$album->thumbnail->Alt}'>";
        }
        $out .="<div class='item-info'><h3>{$album->title}</h3><h4>{$album->thumbnail->tags}</h4></div>";
        $out .="</a>";
 
    }
 
    echo $out;
}

but still no luck using the module syntax
 

[tpr]

Try this:

foreach($albums as $album){

		// if there's no thumbnail no need to do anything
		if(!$album->thumbnail) continue;

		// save srcset tag to a variable
		$srcset = $album->thumbnail->srcset('thumbnail', 'lazyload my-class inline-block', array('quality' => 80));

        $out .="<a href='{$album->url}' class='item {$album->thumbnail->tags} {$album->thumbnail->orientation}'>";
        if($album->images){
            $out .="<img $srcset alt='{$album->thumbnail->Alt}'>";
        }
        $out .="<div class='item-info'><h3>{$album->title}</h3><h4>{$album->thumbnail->tags}</h4></div>";
        $out .="</a>";
 
    }

It's written in browser so double check the syntax.

Edited July 15, 2016 by tpr
remove "src" from markup

[jploch]

Its still not working. No images or html gets rendered from this function (rest of the page looks fine).
There are no error messages (debug mode turned on), so I guess the syntax is fine.
I use the image extra module with this. Could this be a problem?Anyway thanks for your help! 

Here is the complete code:

// album list function ----------------------
function albumList(){
 
    // Get the list of albums 
    $albums = wire("pages")->find("parent=/work/, template=project, limit=100, sort=sort");
 
    $out =" ";
 
    //Loop through the pages
    foreach($albums as $album){

        // if there's no thumbnail no need to do anything
        if(!$album->thumbnail) continue;

        // save srcset tag to a variable
        $srcset = $album->thumbnail->srcset('thumbnail', 'lazyload my-class inline-block', array('quality' => 80));

        $out .="<a href='{$album->url}' class='item {$album->thumbnail->tags} {$album->thumbnail->orientation}'>";
        if($album->images){
            $out .="<img $srcset alt='{$album->thumbnail->Alt}'>";
        }
        $out .="<div class='item-info'><h3>{$album->title}</h3><h4>{$album->thumbnail->tags}</h4></div>";
        $out .="</a>";
 
    }
}

 

[tpr]

Do you have "return $out;" at the end of the function? If not, is there any generated markup? Or is any js or 404 error in the debug console (browser Inspector)?

[jploch]

I forgot the "echo $out;" at the end.
Now I feel a little stupid. My only excuse is that its monday morning without coffee

Everything is working now!
Thank you for this module and your patience with my problems!!


 

[jploch]

Hi!

I have another problem with this.
When I test my images on different resolutions, there seems to be a problem with loading the correct resources.
The images that are created in the assets folder are fine, but most of the time just the biggest image gets loaded.
I testet this with resizing the browser, reloading the page and saving the image and looking at the size.

Here are my module settings in PW:
 "albumimage": [
          [360, null], [720, null], [1300, null], [1600, null]
    ]

This is the generated markup:

<img src="/website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.360x0.jpg" data-srcset="/website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.360x0.jpg 360w, /website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.720x0.jpg 720w, /website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.1300x0.jpg 990w, /website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.1600x0.jpg 1300w" data-sizes="(max-width: 1600px) calc(100vw - 20px), 1600px" class="inline-block lazyloaded" alt="" sizes="(max-width: 1600px) calc(100vw - 20px), 1600px" srcset="/website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.360x0.jpg 360w, /website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.720x0.jpg 720w, /website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.1300x0.jpg 990w, /website_susannerudolf/site/assets/files/1184/logo_wirtschaftsclub-stuttgart.1600x0.jpg 1300w">

Thanks for your help!

[tpr]

Well, the first srcset (360,null) shouldn't be null, but perhaps this isn't the problem. Lazysizes uses the largest image even if you resize the browser. So if the page loads in desktop size, and you downsize it to 400px wide, it won't load the smaller images. In my tests it works only upwards (from small to large size).

[jploch]

I don't know the exact sizes of the images thats why I just set the width.
But thanks for your explanation. I will test it on different devices and see if its working

[ukyo]

@tpr thanks for module, can you add support for width and height attribute support for <img> tag ? Width and height attribute values could come from src attribute.

// My custom hook for $image->alt() function
$this->addHook("Pageimage::alt", function (HookEvent $event) {
    $image = $event->object;
    $return = ($image->description != '') ? $image->description : pathinfo($image->filename, PATHINFO_FILENAME);
    $event->return = " alt='{$return}'";
});

// Json array
{
    "list": [
        [400, 300], [687, 515], [385, 290], [490, 370]
    ]
}

// my usage
<img <?php echo $image->srcset('list', 'lazyload'), $image->alt(); ?>>

// result
<img src="/site/assets/files/1072/peoplelikeus-antifouling-001.400x300.jpg" data-srcset="/site/assets/files/1072/peoplelikeus-antifouling-001.400x300.jpg 480w, /site/assets/files/1072/peoplelikeus-antifouling-001.687x515.jpg 768w, /site/assets/files/1072/peoplelikeus-antifouling-001.385x290.jpg 960w, /site/assets/files/1072/peoplelikeus-antifouling-001.490x370.jpg 1220w" data-sizes="(max-width: 1220px) calc(100vw - 20px), 1220px" class="lazyload" alt='peoplelikeus-antifouling-001'>

// for this result width and height attributes must be 400x300, because our src image size is 400 x 300
<img src="/site/assets/files/1072/peoplelikeus-antifouling-001.400x300.jpg" width="400" height="300" data-srcset="/site/assets/files/1072/peoplelikeus-antifouling-001.400x300.jpg 480w, /site/assets/files/1072/peoplelikeus-antifouling-001.687x515.jpg 768w, /site/assets/files/1072/peoplelikeus-antifouling-001.385x290.jpg 960w, /site/assets/files/1072/peoplelikeus-antifouling-001.490x370.jpg 1220w" data-sizes="(max-width: 1220px) calc(100vw - 20px), 1220px" class="lazyload" alt='peoplelikeus-antifouling-001'>

For the moment i edited you module line 180 (don't like custom adds)

$markup = 'src="' . $fallbackImgSrc . '" width="'.$fallbackImg->width.'" height="'.$fallbackImg->height.'" ' . $markup;

 

[tpr]

I'm not against it, but setting the lowest width-height size will be inappropriate on larger sizes (eg. 687x515 on the next breakpoint in your example). Or do you think it's OK?

[ukyo]

On 27.08.2016 at 10:34 PM, tpr said:

I'm not against it, but setting the lowest width-height size will be inappropriate on larger sizes (eg. 687x515 on the next breakpoint in your example). Or do you think it's OK?

I tested it and its look bad idea, if you add width and height for img tag, responsive display not working well. I removed my changes.

and can you test this image tag in chrome browser & safari :

<img
                        src="http://placehold.it/400x300"
                        data-srcset="http://placehold.it/400x300 480w, http://placehold.it/667x515 768w, http://placehold.it/385x290 960w, http://placehold.it/490x370 1220w"
                        data-sizes="(max-width: 1220px) calc(100vw - 20px), 1220px"
                        class="lazyload uk-width-1-1">

This tag generated by your module just images replaced with placehold.it, this tag working only in firefox.

I am loading js files manuelly do i need to add extra javascript codes ?

<?php
    $lazySizes = array(
        'styles/bower_components/lazysizes/lazysizes.min.js',
        'styles/bower_components/picturefill/dist/picturefill.min.js',
        'styles/bower_components/lazysizes/plugins/attrchange/ls.attrchange.min.js',
        'styles/bower_components/lazysizes/plugins/bgset/ls.bgset.min.js'
    );
    echo "\n\t\t<script src=\"" . AIOM::JS($lazySizes) . "\"></script>";
    ?>

Picture tag working much better, i was has same problem when i frist try lazysizes js, if you check post

there is funtion i made for lazysizes with picture tag, i wll try to add picture mode also. 

This is working for me, for all browsers :

<picture>
                        <!--[if IE 9]><video style='display: none;'><![endif]-->
                        <source srcset='data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==' data-srcset='http://placehold.it/400x300' media='(max-width: 479px)' />
                        <source srcset='data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==' data-srcset='http://placehold.it/667x515' media='(max-width: 767px)' />
                        <source srcset='data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==' data-srcset='http://placehold.it/385x290' media='(max-width: 959px)' />
                        <!--[if IE 9]></video><![endif]-->
                        <img src='data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==' data-srcset='http://placehold.it/490x370' alt='' class="lazyload uk-width-1-1" />
                    </picture>

 

Edited August 29, 2016 by ukyo
Added new usages

[Pravin]

I have issues regarding responsive images. I have used Markup srcset for images but the problem is I am not able to call the images added in repeater field as well as Multiple image field..

 

My code

<?php
    $i = 2;
    foreach($page->page_content as $each) {
    if( $i%2 == 0 ){
?>
   <section class="imageblock about-1">
          <div class="imageblock__content col-md-6 col-sm-4 pos-left">
              <div class="background-image-holder">
<img alt="image"
 src=" '<?php echo $each->single_image->srcset('mode07');?>' "/>
              </div>
          </div>
                  <div class="container container-body">
                      <div class="row">
                          <div class="col-md-5 col-md-push-7 col-sm-8 col-sm-push-4">
                              <?php echo $each->body; ?>
                          </div>
                      </div>
                      <!--end of row-->
                  </div>
                  <!--end of container-->
     
   </section>

[3fingers]

Hi Pravin,

I think common mistake of newbies of the forum is to not contextualize the situation they're are asking help with.

If you want help (and this is the right place :)) try first to help us understand at best what is your setup. Take for example some screenshots of your fields (the repeater containing the images or whatever it is involved in this particular situation).

Hint: wrap html, php, or js code inside the "<>" icon you have in the editor, it greatly improves readability

[Tyssen]

Is it possible to have different breakpoints for different image sets? Or some way to control the value for the sizes attribute?

For instance, for hero images that are going to be full width of the page I'll want different sizes than if I'm displaying a small author headshot which just needs a 2x or 3x version for HiDPI devices.