ai-app-factory / docs /alpinejs /_Templating.md
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Templating
==========
Alpine offers a handful of useful directives for manipulating the DOM on a web page.
Let's cover a few of the basic templating directives here, but be sure to look through the available directives in the sidebar for an exhaustive list.
[Text content](#text-content)
-----------------------------
Alpine makes it easy to control the text content of an element with the `x-text` directive.
<div x-data="{ title: 'Start Here' }"> <h1 x-text="title"></h1></div>
<div x-data="{ title: 'Start Here' }">
<h1 x-text="title"></h1>
</div>
**Start Here**
Now, Alpine will set the text content of the `<h1>` with the value of `title` ("Start Here"). When `title` changes, so will the contents of `<h1>`.
Like all directives in Alpine, you can use any JavaScript expression you like. For example:
<span x-text="1 + 2"></span>
<span x-text="1 + 2"></span>
3
The `<span>` will now contain the sum of "1" and "2".
[β†’ Read more about `x-text`](/directives/text)
[Toggling elements](#toggling-elements)
---------------------------------------
Toggling elements is a common need in web pages and applications. Dropdowns, modals, dialogues, "show-more"s, etc... are all good examples.
Alpine offers the `x-show` and `x-if` directives for toggling elements on a page.
### [`x-show`](#x-show)
Here's a simple toggle component using `x-show`.
<div x-data="{ open: false }"> <button @click="open = ! open">Expand</button>Β  <div x-show="open"> Content... </div></div>
<div x-data="{ open: false }">
<button @click="open = ! open">Expand</button>
<div x-show="open">
Content...
</div>
</div>
Expand
Content...
Now the entire `<div>` containing the contents will be shown and hidden based on the value of `open`.
Under the hood, Alpine adds the CSS property `display: none;` to the element when it should be hidden.
[β†’ Read more about `x-show`](/directives/show)
This works well for most cases, but sometimes you may want to completely add and remove the element from the DOM entirely. This is what `x-if` is for.
### [`x-if`](#x-if)
Here is the same toggle from before, but this time using `x-if` instead of `x-show`.
<div x-data="{ open: false }"> <button @click="open = ! open">Expand</button>Β  <template x-if="open"> <div> Content... </div> </template></div>
<div x-data="{ open: false }">
<button @click="open = ! open">Expand</button>
<template x-if="open">
<div>
Content...
</div>
</template>
</div>
Expand
Notice that `x-if` must be declared on a `<template>` tag. This is so that Alpine can leverage the existing browser behavior of the `<template>` element and use it as the source of the target `<div>` to be added and removed from the page.
When `open` is true, Alpine will append the `<div>` to the `<template>` tag, and remove it when `open` is false.
[β†’ Read more about `x-if`](/directives/if)
[Toggling with transitions](#toggling-with-transitions)
-------------------------------------------------------
Alpine makes it simple to smoothly transition between "shown" and "hidden" states using the `x-transition` directive.
> `x-transition` only works with `x-show`, not with `x-if`.
Here is, again, the simple toggle example, but this time with transitions applied:
<div x-data="{ open: false }"> <button @click="open = ! open">Expands</button>Β  <div x-show="open" x-transition> Content... </div></div>
<div x-data="{ open: false }">
<button @click="open = ! open">Expands</button>
<div x-show="open" x-transition>
Content...
</div>
</div>
Expands
Content...
Let's zoom in on the portion of the template dealing with transitions:
<div x-show="open" x-transition>
<div x-show="open" x-transition>
`x-transition` by itself will apply sensible default transitions (fade and scale) to the toggle.
There are two ways to customize these transitions:
* Transition helpers
* Transition CSS classes.
Let's take a look at each of these approaches:
### [Transition helpers](#transition-helpers)
Let's say you wanted to make the duration of the transition longer, you can manually specify that using the `.duration` modifier like so:
<div x-show="open" x-transition.duration.500ms>
<div x-show="open" x-transition.duration.500ms>
Expands
Content...
Now the transition will last 500 milliseconds.
If you want to specify different values for in and out transitions, you can use `x-transition:enter` and `x-transition:leave`:
<div x-show="open" x-transition:enter.duration.500ms x-transition:leave.duration.1000ms>
<div
x-show="open"
x-transition:enter.duration.500ms
x-transition:leave.duration.1000ms
>
Expands
Content...
Additionally, you can add either `.opacity` or `.scale` to only transition that property. For example:
<div x-show="open" x-transition.opacity>
<div x-show="open" x-transition.opacity>
Expands
Content...
[β†’ Read more about transition helpers](/directives/transition#the-transition-helper)
### [Transition classes](#transition-classes)
If you need more fine-grained control over the transitions in your application, you can apply specific CSS classes at specific phases of the transition using the following syntax (this example uses [Tailwind CSS](https://tailwindcss.com/)):
<div x-show="open" x-transition:enter="transition ease-out duration-300" x-transition:enter-start="opacity-0 transform scale-90" x-transition:enter-end="opacity-100 transform scale-100" x-transition:leave="transition ease-in duration-300" x-transition:leave-start="opacity-100 transform scale-100" x-transition:leave-end="opacity-0 transform scale-90">...</div>
<div
x-show="open"
x-transition:enter="transition ease-out duration-300"
x-transition:enter-start="opacity-0 transform scale-90"
x-transition:enter-end="opacity-100 transform scale-100"
x-transition:leave="transition ease-in duration-300"
x-transition:leave-start="opacity-100 transform scale-100"
x-transition:leave-end="opacity-0 transform scale-90"
>...</div>
Expands
Content...
[β†’ Read more about transition classes](/directives/transition#applying-css-classes)
[Binding attributes](#binding-attributes)
-----------------------------------------
You can add HTML attributes like `class`, `style`, `disabled`, etc... to elements in Alpine using the `x-bind` directive.
Here is an example of a dynamically bound `class` attribute:
<button x-data="{ red: false }" x-bind:class="red ? 'bg-red' : ''" @click="red = ! red"> Toggle Red</button>
<button
x-data="{ red: false }"
x-bind:class="red ? 'bg-red' : ''"
@click="red = ! red"
>
Toggle Red
</button>
Toggle Red
As a shortcut, you can leave out the `x-bind` and use the shorthand `:` syntax directly:
<button ... :class="red ? 'bg-red' : ''">
<button ... :class="red ? 'bg-red' : ''">
Toggling classes on and off based on data inside Alpine is a common need. Here's an example of toggling a class using Alpine's `class` binding object syntax: (Note: this syntax is only available for `class` attributes)
<div x-data="{ open: true }"> <span :class="{ 'hidden': ! open }">...</span></div>
<div x-data="{ open: true }">
<span :class="{ 'hidden': ! open }">...</span>
</div>
Now the `hidden` class will be added to the element if `open` is false, and removed if `open` is true.
[Looping elements](#looping-elements)
-------------------------------------
Alpine allows for iterating parts of your template based on JavaScript data using the `x-for` directive. Here is a simple example:
<div x-data="{ statuses: ['open', 'closed', 'archived'] }"> <template x-for="status in statuses"> <div x-text="status"></div> </template></div>
<div x-data="{ statuses: ['open', 'closed', 'archived'] }">
<template x-for="status in statuses">
<div x-text="status"></div>
</template>
</div>
open
closed
archived
Similar to `x-if`, `x-for` must be applied to a `<template>` tag. Internally, Alpine will append the contents of `<template>` tag for every iteration in the loop.
As you can see the new `status` variable is available in the scope of the iterated templates.
[β†’ Read more about `x-for`](/directives/for)
[Inner HTML](#inner-html)
-------------------------
Alpine makes it easy to control the HTML content of an element with the `x-html` directive.
<div x-data="{ title: '<h1>Start Here</h1>' }"> <div x-html="title"></div></div>
<div x-data="{ title: '<h1>Start Here</h1>' }">
<div x-html="title"></div>
</div>
Start Here
==========
Now, Alpine will set the text content of the `<div>` with the element `<h1>Start Here</h1>`. When `title` changes, so will the contents of `<h1>`.
> ⚠️ Only use on trusted content and never on user-provided content. ⚠️ Dynamically rendering HTML from third parties can easily lead to XSS vulnerabilities.
[β†’ Read more about `x-html`](/directives/html)
[← State](/essentials/state)
[Events β†’](/essentials/events)
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