x-for

Alpine's x-for directive allows you to create DOM elements by iterating through a list. Here's a simple example of using it to create a list of colors based on an array.

<ul x-data="{ colors: ['Red', 'Orange', 'Yellow'] }">
    <template x-for="color in colors">
        <li x-text="color"></li>
    </template>
</ul>

You may also pass objects to x-for.

<ul x-data="{ car: { make: 'Jeep', model: 'Grand Cherokee', color: 'Black' } }">
    <template x-for="(value, index) in car">
        <li>
            <span x-text="index"></span>: <span x-text="value"></span>
        </li>
    </template>
</ul>

There are two rules worth noting about x-for:

x-for MUST be declared on a <template> element. That <template> element MUST contain only one root element

Keys

It is important to specify unique keys for each x-for iteration if you are going to be re-ordering items. Without dynamic keys, Alpine may have a hard time keeping track of what re-orders and will cause odd side-effects.

<ul x-data="{ colors: [
    { id: 1, label: 'Red' },
    { id: 2, label: 'Orange' },
    { id: 3, label: 'Yellow' },
]}">
    <template x-for="color in colors" :key="color.id">
        <li x-text="color.label"></li>
    </template>
</ul>

Now if the colors are added, removed, re-ordered, or their "id"s change, Alpine will preserve or destroy the iterated <li>elements accordingly.

Accessing indexes

If you need to access the index of each item in the iteration, you can do so using the ([item], [index]) in [items] syntax like so:

<ul x-data="{ colors: ['Red', 'Orange', 'Yellow'] }">
    <template x-for="(color, index) in colors">
        <li>
            <span x-text="index + ': '"></span>
            <span x-text="color"></span>
        </li>
    </template>
</ul>

You can also access the index inside a dynamic :key expression.

<template x-for="(color, index) in colors" :key="index">

Iterating over a range

If you need to simply loop n number of times, rather than iterate through an array, Alpine offers a short syntax.

<ul>
    <template x-for="i in 10">
        <li x-text="i"></li>
    </template>
</ul>

i in this case can be named anything you like.

Despite not being included in the above snippet, x-for cannot be used if no parent element has x-data defined. → Read more about x-data

Contents of a <template>

As mentioned above, an <template> tag must contain only one root element.

For example, the following code will not work:

<template x-for="color in colors">
    <span>The next color is </span><span x-text="color">
</template>

but this code will work:

<template x-for="color in colors">
    <p>
        <span>The next color is </span><span x-text="color">
    </p>
</template>

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