I’m working on a new web app that contains a sliding out panel with some additional information on the selected element. This panel can be closed by the user via the ESC key. The implementation on initializing the panel seems very straight forward:

1
2
3
4
5
6
7
8
9
10
11

class Panel() {
  init() {

    document.addEventListener("keydown", function(event) {
      if(event.key === "Escape"){
        //close the panel
      }
    });
    
  }
}

Problem is: the panel, which is part of the basic HTML, will be initialized with its content and functionality in a ES6 class. So … on every init, another event listener is added.

You can easily figure that out, by calling getEventListeners(document) in the Chrome DevTools:

Continue reading ...

The Template Literals introduced with ES6 are very useful to deal with multiline strings, because they support embedded expressions. Gone are the days of endless string concatination or replacing variables in a string by using RegEx.

Instead of…

1
2
3
4
5
6
7
8

var url = ...
var file = ...

var template = 
  '<div class="photo">' + 
     '<a href="' + url + "' + 
        'style="background-image: url(' + file + ')"</a>' + 
  '</div>'

… you can write:

1
2
3
4
5
6
7
8
9

var url = ...
var file = ...

var template = `
  <div class="photo">
    <a href="${url}/"
    style="background-image: url(${file});"></a>
  </div>
`,

It’s much cleaner and easier to handle, as you can copy your needed HTML right into your code and surround it by backtick (!) characters. Insert your variable placeholders (expressions), indicated by a dollar sign and curly braces, and you are done.

But there is one “restriction”, you have to be aware of: the interpolation (substitution of the expressions) is done at declaration time and not at runtime. You can’t define your literals seperatly, take one and make your substitution as you need it, like you would do with Handlebars or other templating engines. Therefore the name template literals is a bit misleading. But … there is a way to achieve this anyway…

Continue reading ...

In this episode of the Discoveries (almost) everything is about images and the web. There are so many pitfalls to do it wrong, but many more possibilities to do it right, especially with these resources I found in the last few weeks.

• ASP.NET Core Image Resizing Middleware
• Best way to lazy load images for maximum performance
• image orientation on the web
• cosha - Colorful shadows for your images
• parax-bg - Parallax Backgrounds
• parax - Parallax Elements
• Luminous Lightbox
• Tiny-Swiper - Image Carousel

Continue reading ...

In 2019 I was on a short, stressful business trip to Dehli, India and one night we had the opportunity to relax a bit by driving around the city and visit some beautiful places of interest. I had no gear at all, just my Sony smartphone, but it is remarkable how good this worked out.

Continue reading ...

I’m a travel and event photo enthusiast, which means I’m shooting a lot of photographs on vacation or at special events only a few times a year. After I’m back home and start the image processing, I develop a particular look for my images of the past vacation or event. This has a lot to do with my mood and is very intuitive. Not all images are the same in terms of composition and light and so I create usually 3 or 4 different presets each time during image processing.

Back in 2019, I was traveling around Israel, a fascinating country where almost every wall has a story to tell and I was listening through my viewfinder. Here I want to share the presets with you…

Continue reading ...

In all times photography was a process: First you shoot you images, then you edit them and in the third step you publish them elsewhere.

Today Adobe Lightroom is a de-facto standard in photo processing, especially when you shoot RAW images. And I mean Lightroom Classic and not the new web/smartphone based software, which doesn’t come even close to the desktop application yet.

I use Lightroom for all purposes after I shot my images: editing, cataloguing, managing and … publishing. On publishing Lightroom offers you two approaches: Export and Publish. While Export is mainly for creating JPG copies of edited RAW images, Publish goes one step further and gives you the ability to do “something” with your exported JPG’s, for example upload them on Flickr, Instagram, 500px or to your own web server via FTP. Major difference to Export is, that Publish keeps your images in sync. Everytime you change the source images, the defined publish services recognizes and offer you to re-publish your image.

In the past years I tried a lot of Lightroom plugins for publishing on several platforms, but it doesn’t work out for long, because all these platforms change their API almost every year (or are stamped) and the sparely maintained 3rd party plugins break.

My workflow for quite some time is to publish my photos on the hard drive, in a folder, which is synced via Dropbox with the cloud. From there I distribute them further.

Continue reading ...

It is so amazing how many cool stuff developers around the world are producing these days. Or they do what they always do, but I have more time to read about their smart ideas and solutions. This month I have 8 pearls for you:

• waitForElementTransition()
• Using Flexbox and text ellipsis together
• Using Trello as a Super Simple CMS
• Memorize Scroll Position Across Page Loads
• A free guide to HTML5 <head> elements
• BVSelect - Vanilla JS
• A clock that represents the time as hex color values
• Animate.css - Just-add-water CSS animations

Continue reading ...

A while ago I wrote a Single Page Application (SPA) with jQuery and and decided to use some useful plugins to avoid reinventing the wheel. To keep the delivered sources small, I used the bundler Gulp, to pack all JS plugins in a single file and another one for my custom JS code. I used the same procedure with the CSS files.

The SPA contained only a single HTML file in which all bundeled sources and needed HTML template blocks were included, in order to load most of the stuff while starting the app, when the users sees a GMail-like loading screen.

But the whole thing had one disadvantage: Debugging for example in Chrome Dev Tool is not a joy, if the code is packed with Gulp Concat and Gulp Uglify. It would be much more convenient, if the source loading can be done depending on the environment.

Continue reading ...

It is always nice to point the readers of your blog’s articles to related posts, they might be interested in. They stay a little longer to understand what you have to offer and increases the likelihood that they become loyal readers, followers or subscribers. Related posts has become a standard on delivering news and posts.

In the default Hexo theme Landscape, on which this blog is based, there is no such function built in, but as the Hexo community is very busy, there are some plugins you can use.

Continue reading ...

Some articles I stumble upon in my daily routine of reading news and blogs are diving very deep in a certain topic, especially if they are describing the basics of techniques I use every day.

All of the following reading tips are of the type “ahh, that’s why this works like that” or “uuh, I just scatch on the surface on that”. Take your time and read the articles in detail. We all never stop learning and it’s a pleasure to do so…

CSS

• CSS Viewport Units
• Grid for layout, Flexbox for components
• How CSS Perspective Works
• Linearly Scale font-size with CSS clamp() Based on the Viewport
• Learn CSS Centering

JavaScript

• The Flavors of Object-Oriented Programming (in JavaScript)
• Understanding the Event Loop, Callbacks, Promises, and Async/Await in JavaScript

Continue reading ...

In some occasions it is necessary to know which device a user is using while writing JavaScript Web Apps. Should be nothing regarding layout, because for this we have CSS Media Queries.

Somewhere around 2011 W3C introduced matchMedia(), which returns a MediaQueryList object that can be used to detemnine if the document matches the media query string. The using is pretty straightforward and feels a bit like RegEx matching in JS:

1
2
3
4

const mediaQuery = window.matchMedia('(min-width: 1025px)')
if (mediaQuery.matches) {
  // do something...  
}

If you are interested in this API, you will find good introductions to the topic here, here and here (German).

One point of criticism on this pure JS approach can be, that you have to maintain the breakpoints in addition to CSS … but why not use these existing breakpoints in JS?

Continue reading ...

As this blog is a static one, generated by Hexo and hostet at GitHub, the page which was shown, when a user enters an Url which points to nowhere, was the default GitHub 404 page.

Continue reading ...