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<h1>Click to Load Website Images</h1>
<p>2021-03-25</p>
<p>In my previous post about <a href="https://uglyduck.ca/#2021-03-22-89-posts-one-file">switching my Jekyll blog over to PHPetite</a>, I briefly mentioned how I only loaded in article images if the user <em>clicked or tapped</em> the empty file element.</p>
<p>In this post, I'm going to quickly breakdown the update I've done to my blog's images since then and how you can easily implement the same thing in your own project.</p>
<h2>Update</h2>
<p>As pointed out by Gabriel <a href="https://github.com/bradleytaunt/phpetite/issues/1">in this Github issue</a>, this concept breaks things slightly for RSS users. Since then, I have just set the default images on this blog to <code>display: none</code> and render them as <code>block</code> elements when their specific <code>section</code> is loaded into the DOM visibly.</p>
<p>The example below is remaining the same as it was, to still provide context for this post.</p>
<h2>Live Demo</h2>
<p>Before we jump head first into the details, let's take a look at what we will be creating:</p>
<p><figure>
    <div class="img-parent">
    <img loading="lazy" src="/placeholder-image.webp" onclick="this.src='/public/images/aqua-ui-css-buttons.webp'" alt="Aqua UI buttons">
    </div>
    <figcaption><b>Click the placeholder to load in the real image</b><br>Example Dribbble shot for testing. Feel free to click the default image in order to load the correct Dribbble source. <a href="/public/images/aqua-ui-css-buttons.webp">View full size image</a>.</figcaption>
</figure></p>
<p>Pretty neat, eh? Well let's get into the nitty gritty.</p>
<h2>The Code</h2>
<p>Personally, I place everything into a <code>figure</code> element to keep things contained and clean - but this isn't required by any means. We then include our <code>img</code> and <code>figcaption</code> elements. That's it.</p>
<pre><code>&lt;figure&gt;
    &lt;img src=&quot;/placeholder-image.webp&quot; onclick=&quot;this.src='https://res.cloudinary.com/bradtaunt/image/fetch/q_auto:low/v1570124593/https://uglyduck.ca/public/images/aqua-ui-css-buttons.webp'&quot; alt=&quot;Aqua UI buttons&quot;&gt;
    &lt;figcaption&gt;&lt;b&gt;Click the placeholder to load in the real image&lt;/b&gt;&lt;br&gt;
        Example Dribbble shot for testing. Feel free to click the default image in order to load the correct Dribbble source.
        &lt;a href=&quot;https://res.cloudinary.com/bradtaunt/image/fetch/q_auto:low/v1570124593/https://uglyduck.ca/public/images/aqua-ui-css-buttons.webp&quot;&gt;View full size image&lt;/a&gt;.
    &lt;/figcaption&gt;
&lt;/figure&gt;
</code></pre>
<h3>The Image Element</h3>
<p>This is where the <em>magic</em> happens. By default all images will target the default placeholder image: <code>placeholder-image.webp</code>. This image is just 16KB in size and only needs to load in once.</p>
<p>Next we include an inline <code>onclick</code> attribute, which targets the current image's <code>src</code> attribute and changes it based on the URL provided. (Note: I use Cloudinary for my blog's image storage, but you could even host your images relative to your root directory if you wanted)</p>
<p>Now when a user clicks on the placeholder image, the inline <code>onclick</code> pulls in the correct image in it's place.</p>
<h3>Disabled JavaScript</h3>
<p>For users who have JavaScript blocked or disabled we have a decent backup. By including a direct link to the image URL in the <code>figcaption</code> element, we give the user the ability to still view the image in a separate browser tab.</p>
<p>You could get extra fancy and include some <code>noscript</code> tags in your project that maybe render a different placeholder image mentioning they have JavaScript disabled etc, but for my needs that would be overkill.</p>
<h2>Cool - But Why Do This?</h2>
<p>Bandwidth is a limited resource for a lot of users around the world. As designers and developers it's best to respect this fact and only load in elements as the user <em>requires</em> them. Every little bit helps.</p>
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