Reactivity
Declare state
Update state
Computed state
import { createSignal } from "solid-js";
export default function DoubleCount() {
const [count] = createSignal(10);
const doubleCount = () => count() * 2;
return <div>{doubleCount()}</div>;
}
Templating
Minimal template
Styling
import "./style.css";
export default function CssStyle() {
return (
<>
<h1 class="title">I am red</h1>
<button style={{ "font-size": "10rem" }}>I am a button</button>
</>
);
}
Loop
import { For } from "solid-js";
export default function Colors() {
const colors = ["red", "green", "blue"];
return (
<ul>
<For each={colors}>{(color) => <li>{color}</li>}</For>
</ul>
);
}
Event click
import { createSignal } from "solid-js";
export default function Counter() {
const [count, setCount] = createSignal(0);
function incrementCount() {
setCount(count() + 1);
}
return (
<>
<p>Counter: {count()}</p>
<button onClick={incrementCount}>+1</button>
</>
);
}
Dom ref
Conditional
import { createSignal, Switch, Match } from "solid-js";
const TRAFFIC_LIGHTS = ["red", "orange", "green"];
export default function TrafficLight() {
const [lightIndex, setLightIndex] = createSignal(0);
const light = () => TRAFFIC_LIGHTS[lightIndex()];
function nextLight() {
setLightIndex((lightIndex() + 1) % TRAFFIC_LIGHTS.length);
}
return (
<>
<button onClick={nextLight}>Next light</button>
<p>Light is: {light()}</p>
<p>
You must
<Switch>
<Match when={light() === "red"}>
<span>STOP</span>
</Match>
<Match when={light() === "orange"}>
<span>SLOW DOWN</span>
</Match>
<Match when={light() === "green"}>
<span>GO</span>
</Match>
</Switch>
</p>
</>
);
}
<div
x-data="{
TRAFFIC_LIGHTS: ['red', 'orange', 'green'],
lightIndex: 0,
get light() { return this.TRAFFIC_LIGHTS[this.lightIndex] },
nextLight() {
this.lightIndex = (this.lightIndex + 1) % this.TRAFFIC_LIGHTS.length;
}
}"
>
<button x-on:click="nextLight">Next light</button>
<p>Light is: <span x-text="light"></span></p>
<p>
You must
<span x-show="light === 'red'">STOP</span>
<span x-show="light === 'orange'">SLOW DOWN</span>
<span x-show="light === 'green'">GO</span>
</p>
</div>
Lifecycle
On mount
import { createSignal, onMount } from "solid-js";
export default function PageTitle() {
const [pageTitle, setPageTitle] = createSignal("");
onMount(() => {
setPageTitle(document.title);
});
return <p>Page title: {pageTitle()}</p>;
}
On unmount
import { createSignal, onCleanup } from "solid-js";
export default function Time() {
const [time, setTime] = createSignal(new Date().toLocaleTimeString());
const timer = setInterval(() => {
setTime(new Date().toLocaleTimeString());
}, 1000);
onCleanup(() => clearInterval(timer));
return <p>Current time: {time()}</p>;
}
Component composition
Props
import UserProfile from "./UserProfile.jsx";
export default function App() {
return (
<UserProfile
name="John"
age={20}
favouriteColors={["green", "blue", "red"]}
isAvailable
/>
);
}
<!--Alpine JS suggests using a server-side templating engine or another frontend framework in conjunction with Alpine to do this-->
<div
x-data="{
name: 'John',
age: 20,
favouriteColors: ['green', 'blue', 'red'],
isAvailable: true
}"
>
<p>My name is <span x-text="John"></span></p>
<p>My age is <span x-text="age"></span></p>
<p>
My favourite colors are <span x-text="favouriteColors.join(', ')"></span>
</p>
<p>I am <span x-text="isAvailable ? 'available' : 'not available'"></span></p>
</div>
Emit to parent
import { createSignal } from "solid-js";
import AnswerButton from "./AnswerButton.jsx";
export default function App() {
const [isHappy, setIsHappy] = createSignal(true);
function onAnswerNo() {
setIsHappy(false);
}
function onAnswerYes() {
setIsHappy(true);
}
return (
<>
<p>Are you happy?</p>
<AnswerButton onYes={onAnswerYes} onNo={onAnswerNo} />
<p style={{ "font-size": "50px" }}>{isHappy() ? "😀" : "😥"}</p>
</>
);
}
<div
x-data="{ isHappy: true }"
x-on:yes="isHappy = true"
x-on:no="isHappy = false"
>
<p>Are you happy?</p>
<div>
<button x-on:click="$dispatch('yes')">YES</button>
<button x-on:click="$dispatch('no')">NO</button>
</div>
<p style="font-size: 50px" x-text="isHappy ? '😀' : '😥'"></p>
</div>
Slot
import FunnyButton from "./FunnyButton.jsx";
export default function App() {
return <FunnyButton>Click me!</FunnyButton>;
}
<!--Alpine JS suggests using a server-side templating engine or another frontend framework in conjunction with Alpine to do this-->
<button
x-data
x-text="'Click me!'"
style="
background: rgba(0, 0, 0, 0.4);
color: #fff;
padding: 10px 20px;
font-size: 30px;
border: 2px solid #fff;
margin: 8px;
transform: scale(0.9);
box-shadow: 4px 4px rgba(0, 0, 0, 0.4);
transition: transform 0.2s cubic-bezier(0.34, 1.65, 0.88, 0.925) 0s;
outline: 0;
"
>
<span>No content found</span>
</button>
Slot fallback
import FunnyButton from "./FunnyButton.jsx";
export default function App() {
return (
<>
<FunnyButton />
<FunnyButton>I got content!</FunnyButton>
</>
);
}
<!--Alpine JS suggests using a server-side templating engine or another frontend framework in conjunction with Alpine to do this-->
<button
x-data
style="
background: rgba(0, 0, 0, 0.4);
color: #fff;
padding: 10px 20px;
font-size: 30px;
border: 2px solid #fff;
margin: 8px;
transform: scale(0.9);
box-shadow: 4px 4px rgba(0, 0, 0, 0.4);
transition: transform 0.2s cubic-bezier(0.34, 1.65, 0.88, 0.925) 0s;
outline: 0;
"
>
<span>No content found</span>
</button>
<button
x-data
x-text="'I got content!'"
style="
background: rgba(0, 0, 0, 0.4);
color: #fff;
padding: 10px 20px;
font-size: 30px;
border: 2px solid #fff;
margin: 8px;
transform: scale(0.9);
box-shadow: 4px 4px rgba(0, 0, 0, 0.4);
transition: transform 0.2s cubic-bezier(0.34, 1.65, 0.88, 0.925) 0s;
outline: 0;
"
>
<span>No content found</span>
</button>
Context
import { createSignal } from "solid-js";
import { UserContext } from "./UserContext";
import UserProfile from "./UserProfile";
export default function App() {
const [user, setUser] = createSignal({
id: 1,
username: "unicorn42",
email: "[email protected]",
});
function updateUsername(newUsername) {
setUser({ ...user(), username: newUsername });
}
return (
<>
<h1>Welcome back, {user().username}</h1>
<UserContext.Provider value={[user, updateUsername]}>
<UserProfile />
</UserContext.Provider>
</>
);
}
Alpine
Missing snippet Help us to improve Component Party 
Form input
Input text
import { createSignal } from "solid-js";
export default function InputHello() {
const [text, setText] = createSignal("Hello world");
function handleChange(event) {
setText(event.target.value);
}
return (
<>
<p>{text()}</p>
<input value={text()} onInput={handleChange} />
</>
);
}
Checkbox
import { createSignal } from "solid-js";
export default function IsAvailable() {
const [isAvailable, setIsAvailable] = createSignal(false);
function handleChange() {
setIsAvailable((previousValue) => !previousValue);
}
return (
<>
<input
id="is-available"
type="checkbox"
checked={isAvailable()}
onChange={handleChange}
/>
<label for="is-available">Is available</label>
</>
);
}
Radio
import { createSignal } from "solid-js";
export default function PickPill() {
const [picked, setPicked] = createSignal("red");
function handleChange(event) {
setPicked(event.target.value);
}
return (
<>
<div>Picked: {picked()}</div>
<input
id="blue-pill"
checked={picked() === "blue"}
type="radio"
value="blue"
onChange={handleChange}
/>
<label for="blue-pill">Blue pill</label>
<input
id="red-pill"
checked={picked() === "red"}
type="radio"
value="red"
onChange={handleChange}
/>
<label for="red-pill">Red pill</label>
</>
);
}
<div x-data="{ picked: 'red' }">
<div>Picked: <span x-text="picked"></span></div>
<input id="blue-pill" x-model="picked" type="radio" value="blue" />
<label for="blue-pill">Blue pill</label>
<input id="red-pill" x-model="picked" type="radio" value="red" />
<label for="red-pill">Red pill</label>
</div>
Select
import { createSignal, For } from "solid-js";
const colors = [
{ id: 1, text: "red" },
{ id: 2, text: "blue" },
{ id: 3, text: "green" },
{ id: 4, text: "gray", isDisabled: true },
];
export default function ColorSelect() {
const [selectedColorId, setSelectedColorId] = createSignal(2);
function handleChange(event) {
setSelectedColorId(event.target.value);
}
return (
<select value={selectedColorId()} onChange={handleChange}>
<For each={colors}>
{(color) => (
<option value={color.id} disabled={color.isDisabled}>
{color.text}
</option>
)}
</For>
</select>
);
}
<div
x-data="{
selectedColorId: 2,
colors: [
{ id: 1, text: 'red' },
{ id: 2, text: 'blue' },
{ id: 3, text: 'green' },
{ id: 4, text: 'gray', isDisabled: true }
]
}"
>
<select x-model.number="selectedColorId">
<template x-for="color in colors" x-bind:key="color.id">
<option
x-text="color.text"
x-bind:value="color.id"
x-bind:disabled="!!color.isDisabled"
x-bind:selected="color.id === selectedColorId"
></option>
</template>
</select>
</div>
Webapp features
Render app
Fetch data
import { createResource, For, Switch, Match } from "solid-js";
async function fetchUsers() {
return (await fetch("https://randomuser.me/api/?results=3")).json();
}
export default function App() {
const [data] = createResource(fetchUsers);
const users = () => data()?.results;
return (
<Switch>
<Match when={data.loading}>
<p>Fetching users...</p>
</Match>
<Match when={data.error}>
<p>An error occurred while fetching users</p>
</Match>
<Match when={users()}>
<ul>
<For each={users()}>
{(user) => (
<li>
<img src={user.picture.thumbnail} alt="user" />
<p>
{user.name.first} {user.name.last}
</p>
</li>
)}
</For>
</ul>
</Match>
</Switch>
);
}
<div
x-data="
function fetchUsers() {
return {
users: null,
isLoading: false,
error: null,
async init() {
this.isLoading = true;
try {
this.users = (await (await fetch('https://randomuser.me/api/?results=3')).json()).results;
} catch (err) {
this.users = [];
this.error = err
}
this.isLoading = false;
},
};
}
"
>
<template x-if="isLoading">
<p>Loading...</p>
</template>
<template x-if="error">
<p>Error fetching users</p>
</template>
<template x-if="!error">
<ul>
<template x-for="user in users">
<li>
<img
:src="user.picture.thumbnail"
:alt="`picture of ${user.name.first} ${user.name.last}`"
/>
<p x-text="`${user.name.first} ${user.name.last}`"></p>
</li>
</template>
</ul>
</template>
</div>