Tag Archives: animation

Barba.js - Namespace, Rules and Conditions

Barba.js – Namespace, Rules, and Conditions

In the previous tutorial, we’ve covered how to create some cool page transitions using Barba.js and the CSS plugin. Today we will break down some the of terms associated with Barbas page transitions logic.

This will help you to trigger the right transition at the right time.

Barba.js Tutorial

What you will learn:

View Demo →Download Files ↓

What is a namespace?

Barba.js namespace

In simple terms, a namespace is the name of the page that you are leaving or entering.

It is defined on the data-barba="container".

<div class="wrapper" data-barba="container" data-barba-namespace="home">
    ...
</div>

This namespace is very useful if you want to define some rules for your page transitions.

When defining a transition in barba.init({...}) you can tell Barba to use this transition only if some conditions are met. More on conditions later.

There are many custom page transitions in the top award-winning websites.

The developers carefully consider which elements need to be animated out before the new page is animated.

In the CSS page transitions example, I have defined a different namespace for each page to be able to trigger different page transitions.

barba.init({
  transitions: [
    {
      name: 'home',
      to: { namespace: ['home'] },
      leave() {},
      enter() {},
    }, {
      name: 'fade',
      to: { namespace: ['fade'] },
      leave() {},
      enter() {},
    }
  ],
});

If we click on a link that takes us to fade.html, we play the fade transition. If we go to the index.html, the home transition will be used.

That’s how we have used namespace in the transition rule.

How to set rules for transitions?

Barba.js rules for transitions

To define the rules we can specify to, from, or both keywords.

The transition with both keywords will always take a priority, followed by to and from.

namespace is not the only condition that you can use.

To make the rules even more flexible you can also define custom or route if you are using Barba Router.

Think about rules as if this is true, use this transition.

{
    name: 'home',
    to: { namespace: ['home'] },
    leave() {},
    enter() {},
}, {
    name: 'clip',
    // to: { namespace: ['home'] }, // this would make it stronger
    from: { namespace: ['with-cover'] },
    leave() {},
    enter() {},
}

Above are two transitions, one with the rule “to home”, the other one with “from with-cover” namespace.

What if the user goes from with-cover to home? Which one would be used?

The home because to is stronger than from.

If we would add to: { namespace: ['home'] } to the clip transition it would become stronger and would be used instead.

How to use a custom condition for your transition?

Barba.js conditions for transitions

Let’s say you have a special link on a page and you want it to trigger a special transition.

At the same time, you want any other link on that page to trigger a default transition.

You can use the custom condition like this:

{
    name: 'default',
    sync: true,
    from: { namespace: ['home'] },
    leave() {},
    enter() {},
},
{
    name: 'special',
    sync: true,
    from: {
        custom: ({trigger}) => {
            return trigger.text === 'Clip-Path Transition';
        },
        namespace: ['home']
    },
    leave() {},
    enter() {},
}

Any link on the home page would trigger a default transition, but clicking on Clip-Path Transition would trigger the special transition.

Do you see how powerful the rules are? That is how you can craft your page transitions based on many conditions.

custom is the strongest out of all conditions followed by route and namespace.

Barba applies a transition if all conditions are fulfilled.

For more details on the priorities of Barba.js transitions refer to the official documentation.

Do you want to learn even more about Barba.js? Join me in Barba 101 where we will cover Barba API in more detail. I hope to see you there.

Final Demo

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Conclusion

Mastering transition rules and knowing exactly which transition will be trigger when is the key.

Now you know how to use a namespace, set some rules, and use custom conditions for your page transitions.

I can’t wait to see how you will use it on your project.

Do you have any questions related to Barba.js or page transitions? Let me know in the comments.

Barba.js and CSS Plugin Tutorial

Page Transitions Tutorial – Barba.js with CSS Plugin

Do you want to add page transitions to your project but don’t feel comfortable with JavaScript or GreenSock animations?

In this page transitions tutorial, you will learn how to use Barba.js with the CSS plugin to create page transitions purely with CSS.

What you will learn:

View Demo Download Files

Installation

Include @barba/core, @barba/css plugin in your JavaScript module, and tell Barba to use the CSS plugin.

// install via npm or yarn
npm install @barba/core @barba/css
yarn add @barba/core @barba/css
// Include Barba and Barba CSS in your project
import barba from '@barba/core';
import barbaCss from '@barba/css';

// Tell Barba to use the CSS plugin
barba.use(barbaCss);

// Initiate Barba
barba.init();
<body data-barba="wrapper">
    <!-- content that stays the same on all pages - eg. header -->
    <div data-barba="container">
        <!-- content that will change from page to page -->
    </div>
    <!-- content that stays the same on all pages - eg. footer -->
</div>

Barba.js will now add and remove specific CSS classes from the data-barba="container".

These CSS classes will be based on the transitions that we need to specify.

If you are completely new to Barba.js, you can check this tutorial to learn more about the required HTML markup.

How to create fade-in transition on page load

Barba.js CSS Page Transition

To create a simple fade in transition on page load we can use the once hook.

barba.init({
	transitions: [
        {
            once() {}
        }
    ]
});

Barba.js will add and remove the following CSS classes .barba-once, .barba-once-active and .barba-once-to during the transition.

/* Page load animation */
.barba-once {
    opacity: 0;
}
.barba-once-active {
    transition: all 1s linear;
}
.barba-once-to {
    opacity: 1;
}

.barba-once and .barba-once-active will be applied at the start of the transition.

.barba-once-active and .barba-once-to will be applied during the transition.

This hook is called once, because this transition only runs once on the page load.

When the CSS transition is completed, all CSS classes will be removed from the container.

Barba CSS with once hook

How long these classes stay on the container depends on the duration of the CSS transition or animation.

Because the CSS plugin overrides the main once hook, any code inside of once will be ignored. The same applies to the enter and leave hooks.

barba.init({
	transitions: [
        {
            once() {
                console.log('this will be ignored');
            },
            beforeOnce() {
                console.log('shows up BEFORE once transition');
            },
            afterOnce() {
                console.log('shows up AFTER once transition');
            }
        }
    ]
});

If you need to run any code related to the once transition use beforeOnce or afterOnce hooks.

How to customize the name of the CSS class?

You can customize the CSS classes by specifying a name for your transition.

transitions: [
    {
        name: "home",
        once() {}
    }
]

If you specify home as the name, Barba will generate these classes:

.home-once
.home-once-active
.home-once-to

The format of the class is always the same: .[name]-[hook]-[state].

How to create CSS transition between two pages

Barba.js CSS Page Transition

Every page transition has two phases.

Firstly the current page leaves, then the next page enters.

To use CSS transitions between two pages, we need to specify the hooks inside of the Barba transition, even if there is no code inside of them.

transitions: [
    {
        name: "fade",
        leave() {},
        enter() {}
    }
]

Now we can add the CSS transitions to the stylesheet.

/* =Fade out, fade in */
/* Fade out current container */
.fade-leave {
    opacity: 1;
}
.fade-leave-active {
    transition: opacity 0.3s linear;
}
.fade-leave-to {
    opacity: 0;
}

/* Fade in the next container */
.fade-enter {
    opacity: 0;
}
.fade-enter-active {
    transition: opacity 0.3s linear;
}
.fade-enter-to {
    opacity: 1;
}

1. Fade out the current page

Barba CSS with leave hook

In the first phase of the transition, we are fading out the current page.

.fade-leave /* start of the transition */
.fade-leave-active /* CSS transition */
.fade-leave-to /* end of the transition */

The state of our container is opacity: 1 at the start of the transition and opacity: 0 at the end of the transition.

.fade-enter-active class defines the CSS transition that will be used, eg. opacity 0.3s linear.

2. Fade in the next page

Barba CSS with enter hook

In the second phase of the transition, we are fading in the next page.

.fade-enter /* start of the transition */
.fade-enter-active /* CSS transition */
.fade-enter-to /* end of the transition */

We are starting from opacity: 0 and finishing with the page fully visible at opacity: 1.

Of course, you can combine the CSS selectors if the styles are the same.

/* =Fade out, fade in */
/* Fade out current container */
.fade-leave,
.fade-enter-to {
    opacity: 1;
}
.fade-leave-active,
.fade-enter-active {
    transition: opacity 0.3s linear;
}
.fade-leave-to,
.fade-enter {
    opacity: 0;
}

Perfect, this was a simple fade transition, but what if wanted to make a transition where both containers are visible on the page? How would we do that with Barba.js?

Let’s see in the next example.

How to create clip-path transition

Clip-path page transition using Barba.js

Now that you know the basics of Barba.js and the CSS plugin, only your imagination is your limit!

In the next example, we will try to reveal the next page from the center of the screen.

We will clip the incoming page clip-path: circle(0%); at the start and reveal it by specifying clip-path: circle(75%); as the end of the transition.

For this effect, we need to have both containers on the page and Barba has a sync mode build-in exactly for that.

transitions: [
    {
        name: "clip",
        sync: true,
        leave() {},
        enter() {}
    }
]

This will append the next container to the page and we will have both containers available for the transition.

Without the sync mode, the current page is removed from the DOM just before the next page is appended.

/* =Clip-path transition */
.clip-enter { 
    clip-path: circle(0%); 
}
.clip-enter-active {
    position: absolute;
    top: 0;
    z-index: 2;
}
.clip-leave-active,
.clip-enter-active {
    transition: all 0.75s var(--easing);
}
.clip-enter-to { 
    clip-path: circle(75%); 
}
.clip-leave { 
    opacity: 1; 
}
.clip-leave-to { 
    opacity: 0; 
}

With both containers on the page, we are overlapping them by positioning the incoming page on top of the current page.

Then we are animating the clip-path from 0% to 75%.

At the end of the transition, the current page is removed from the DOM and the next is the new current.

Makes sense? I hope it does.

It is quite fun to play with these transitions. Agree?

Let me know in the comments.

How to create a cover transition

Cover page transition using Barba.js

In this example, we will look at how to cover the current page and reveal the next page.

For this effect, we will need to include .transition element inside of each page.

<div data-barba="container">
    <div class="transition">
        <h2>Cover Screen</h2>
    </div>
</div>

This is a simple full-screen element covering the whole viewport, by default it is positioned outside of the viewport using transform: translateY(-100%);.

/* =Transition with cover screen */
.with-cover-leave,
.with-cover-enter,
.with-cover-leave-active .transition,
.with-cover-enter-active .transition {
    transition: transform 0.5s var(--easing);
}
.with-cover-leave .transition {
    transform: translateY(-100%);
}
.with-cover-leave-to .transition,
.with-cover-enter .transition {
    transform: translateY(0);
}
.with-cover-enter-to .transition {
    transform: translateY(100%);
}

In the first phase, we are transitioning the .transition element to translateY(0) using the .with-cover-leave-to .transition selector. This is also the starting position for the enter animation.

Then we are moving the .transition out of the viewport to transform: translateY(100%); using the .with-cover-enter-to .transition selector.

As you can see, the stylesheet could grow quite quickly.

Especially if you want to animate multiple elements in a sequence, that is where JavaScript animations with GreenSock come very handy.

How to create a slide transition

Slide page transition using Barba.js

Now that you know what sync: true does, you can come up with any transition that needs both containers.

One of these transitions could be a slide transition.

.slide-leave,
.slide-enter-to {
    transform: translateX(0);
}
.slide-leave-active,
.slide-enter-active {
    transition: all 0.7s cubic-bezier(0.5, 0.7, 0.4, 1);
}
.slide-leave-to {
    transform: translateX(100%);
}

.slide-enter {
    transform: translateX(-100%);
}
.slide-enter-to {
    position: absolute;
    top: 0;
    left: 0;
}

At the start of the transition, we are using .slide-enter CSS class to position the incoming next page outside of the viewport.

Then we are animating both containers by 100%. The current page goes away from the viewport to translateX(100%) and the next page moves to translateX(0).

The page entering the viewport is positioned absolute during the transition as we have defined in the .slide-enter-to CSS class.

And that is it, now you have learned how to create 4 different page transitions using Barba.js and the CSS Plugin.

Final Demo

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Things to remember

  • You need to add an empty hook to your JS, to use CSS transition for that hook!
  • The JavaScript code in once, enter, leave hooks will be ignored!
  • beforeOnce, afterOnce, beforeEnter, afterEnter, beforeLeave, afterLeave can be used.
  • Currently, there is a bug with the back button not triggering the transition.

Conclusion

As you can see from the above examples, you can create some interesting page transitions using CSS transitions.

You have learned how Barba.js and the CSS plugin works and which CSS classes are applied to your container during the page transition.

Have you seen any cool page transitions on the web?

Let me know in the comments and don’t forget to check out some of my online courses to learn even more about creative front-end development.